Type Checking

Completed type checking as well as formatted files.

miniJava/src/miniJava/AbstractSyntaxTrees/ASTDisplay.java

@@ -22,7 +22,9 @@ public class ASTDisplay implements Visitor<String,Object> {
 
 	/**
 	 * print text representation of AST to stdout
-     * @param ast root node of AST 
+	 * 
+	 * @param ast
+	 *            root node of AST
 	 */
 	public void showTree(AST ast) {
 		System.out.println("======= AST Display =========================");
@@ -34,8 +36,11 @@ public class ASTDisplay implements Visitor<String,Object> {
 
 	/**
 	 * display arbitrary text for a node
-     * @param prefix  spacing to indicate depth in AST
+	 * 
-     * @param text    preformatted node display
+	 * @param prefix
+	 *            spacing to indicate depth in AST
+	 * @param text
+	 *            preformatted node display
 	 */
 	private void show(String prefix, String text) {
 		System.out.println(prefix + text);
@@ -43,8 +48,11 @@ public class ASTDisplay implements Visitor<String,Object> {
 
 	/**
 	 * display AST node by name
-     * @param prefix  spacing to indicate depth in AST
+	 * 
-     * @param node    AST node, will be shown by name
+	 * @param prefix
+	 *            spacing to indicate depth in AST
+	 * @param node
+	 *            AST node, will be shown by name
 	 */
 	private void show(String prefix, AST node) {
 		System.out.println(prefix + node.toString());
@@ -52,7 +60,9 @@ public class ASTDisplay implements Visitor<String,Object> {
 
 	/**
 	 * quote a string
-     * @param text    string to quote
+	 * 
+	 * @param text
+	 *            string to quote
 	 */
 	private String quote(String text) {
 		return ("\"" + text + "\"");
@@ -60,14 +70,15 @@ public class ASTDisplay implements Visitor<String,Object> {
 
 	/**
 	 * increase depth in AST
-     * @param prefix  current spacing to indicate depth in AST
+	 * 
+	 * @param prefix
+	 *            current spacing to indicate depth in AST
 	 * @return new spacing
 	 */
 	private String indent(String prefix) {
 		return prefix + "  ";
 	}
 
-    
 	// /////////////////////////////////////////////////////////////////////////////
 	//
 	// PACKAGE
@@ -85,7 +96,6 @@ public class ASTDisplay implements Visitor<String,Object> {
 		return null;
 	}
 
-    
 	// /////////////////////////////////////////////////////////////////////////////
 	//
 	// DECLARATIONS
@@ -149,7 +159,6 @@ public class ASTDisplay implements Visitor<String,Object> {
 		return null;
 	}
 
-	
 	// /////////////////////////////////////////////////////////////////////////////
 	//
 	// TYPES
@@ -173,7 +182,6 @@ public class ASTDisplay implements Visitor<String,Object> {
 		return null;
 	}
 
-	
 	// /////////////////////////////////////////////////////////////////////////////
 	//
 	// STATEMENTS
@@ -233,7 +241,6 @@ public class ASTDisplay implements Visitor<String,Object> {
 		return null;
 	}
 
-
 	// /////////////////////////////////////////////////////////////////////////////
 	//
 	// EXPRESSIONS
@@ -292,7 +299,6 @@ public class ASTDisplay implements Visitor<String,Object> {
 		return null;
 	}
 
-
 	// /////////////////////////////////////////////////////////////////////////////
 	//
 	// REFERENCES
@@ -324,7 +330,6 @@ public class ASTDisplay implements Visitor<String,Object> {
 		return null;
 	}
 
-    
 	// /////////////////////////////////////////////////////////////////////////////
 	//
 	// TERMINALS

miniJava/src/miniJava/AbstractSyntaxTrees/ArrayType.java

@@ -21,4 +21,3 @@ public class ArrayType extends Type {
 
 	public Type eltType;
 }
-

miniJava/src/miniJava/AbstractSyntaxTrees/AssignStmt.java

@@ -7,8 +7,7 @@ package miniJava.AbstractSyntaxTrees;
 
 import miniJava.SyntacticAnalyzer.SourcePosition;
 
-public class AssignStmt extends Statement
+public class AssignStmt extends Statement {
-{
 	public AssignStmt(Reference r, Expression e, SourcePosition posn) {
 		super(posn);
 		ref = r;

miniJava/src/miniJava/AbstractSyntaxTrees/BaseType.java

@@ -7,8 +7,7 @@ package miniJava.AbstractSyntaxTrees;
 
 import miniJava.SyntacticAnalyzer.SourcePosition;
 
-public class BaseType extends Type
+public class BaseType extends Type {
-{
 	public BaseType(TypeKind t, SourcePosition posn) {
 		super(t, posn);
 	}

miniJava/src/miniJava/AbstractSyntaxTrees/BinaryExpr.java

@@ -7,9 +7,9 @@ package miniJava.AbstractSyntaxTrees;
 
 import miniJava.SyntacticAnalyzer.SourcePosition;
 
-public class BinaryExpr extends Expression
+public class BinaryExpr extends Expression {
-{
+	public BinaryExpr(Operator o, Expression e1, Expression e2,
-    public BinaryExpr(Operator o, Expression e1, Expression e2, SourcePosition posn){
+			SourcePosition posn) {
 		super(posn);
 		operator = o;
 		left = e1;

miniJava/src/miniJava/AbstractSyntaxTrees/BlockStmt.java

@@ -7,8 +7,7 @@ package miniJava.AbstractSyntaxTrees;
 
 import miniJava.SyntacticAnalyzer.SourcePosition;
 
-public class BlockStmt extends Statement
+public class BlockStmt extends Statement {
-{
 	public BlockStmt(StatementList sl, SourcePosition posn) {
 		super(posn);
 		this.sl = sl;

miniJava/src/miniJava/AbstractSyntaxTrees/CallExpr.java

@@ -7,8 +7,7 @@ package miniJava.AbstractSyntaxTrees;
 
 import miniJava.SyntacticAnalyzer.SourcePosition;
 
-public class CallExpr extends Expression
+public class CallExpr extends Expression {
-{
 	public CallExpr(Reference f, ExprList el, SourcePosition posn) {
 		super(posn);
 		functionRef = f;

miniJava/src/miniJava/AbstractSyntaxTrees/CallStmt.java

@@ -7,8 +7,7 @@ package miniJava.AbstractSyntaxTrees;
 
 import miniJava.SyntacticAnalyzer.SourcePosition;
 
-public class CallStmt extends Statement
+public class CallStmt extends Statement {
-{
 	public CallStmt(Reference m, ExprList el, SourcePosition posn) {
 		super(posn);
 		methodRef = m;

miniJava/src/miniJava/AbstractSyntaxTrees/ClassDecl.java

@@ -13,6 +13,9 @@ public class ClassDecl extends Declaration {
 		super(cn, null, posn);
 		fieldDeclList = fdl;
 		methodDeclList = mdl;
+		
+		Identifier ident = new Identifier(cn, posn);
+		type = new ClassType(ident, posn);
 	}
 
 	public <A, R> R visit(Visitor<A, R> v, A o) {

miniJava/src/miniJava/AbstractSyntaxTrees/ClassDeclList.java

@@ -7,8 +7,7 @@ package miniJava.AbstractSyntaxTrees;
 
 import java.util.*;
 
-public class ClassDeclList implements Iterable<ClassDecl>
+public class ClassDeclList implements Iterable<ClassDecl> {
-{
 	public ClassDeclList() {
 		classDeclList = new ArrayList<ClassDecl>();
 	}
@@ -31,4 +30,3 @@ public class ClassDeclList implements Iterable<ClassDecl>
 
 	private List<ClassDecl> classDeclList;
 }
-

miniJava/src/miniJava/AbstractSyntaxTrees/ClassType.java

@@ -7,8 +7,7 @@ package miniJava.AbstractSyntaxTrees;
 
 import miniJava.SyntacticAnalyzer.SourcePosition;
 
-public class ClassType extends Type
+public class ClassType extends Type {
-{
 	public ClassType(Identifier cn, SourcePosition posn) {
 		super(TypeKind.CLASS, posn);
 		className = cn;

miniJava/src/miniJava/AbstractSyntaxTrees/Declaration.java

@@ -18,7 +18,8 @@ public abstract class Declaration extends AST {
 	@Override
 	public String toString() {
 		if (posn != null) {
-			return this.name + "(Line: " + posn.line + ", Column: " + posn.col + ")";
+			return this.name + "(Line: " + posn.line + ", Column: " + posn.col
+					+ ")";
 		} else {
 			return super.toString();
 		}

miniJava/src/miniJava/AbstractSyntaxTrees/Declarators.java

@@ -4,7 +4,8 @@ import miniJava.SyntacticAnalyzer.SourcePosition;
 
 public class Declarators {
 
-	public Declarators(boolean isPrivate, boolean isStatic, Type mt, SourcePosition posn) {
+	public Declarators(boolean isPrivate, boolean isStatic, Type mt,
+			SourcePosition posn) {
 		this.isPrivate = isPrivate;
 		this.isStatic = isStatic;
 		this.mt = mt;

miniJava/src/miniJava/AbstractSyntaxTrees/ExprList.java

@@ -7,8 +7,7 @@ package miniJava.AbstractSyntaxTrees;
 
 import java.util.*;
 
-public class ExprList implements Iterable<Expression>
+public class ExprList implements Iterable<Expression> {
-{
 	public ExprList() {
 		elist = new ArrayList<Expression>();
 	}

miniJava/src/miniJava/AbstractSyntaxTrees/FieldDecl.java

@@ -9,7 +9,8 @@ import miniJava.SyntacticAnalyzer.SourcePosition;
 
 public class FieldDecl extends MemberDecl {
 
-	public FieldDecl(boolean isPrivate, boolean isStatic, Type t, String name, SourcePosition posn){
+	public FieldDecl(boolean isPrivate, boolean isStatic, Type t, String name,
+			SourcePosition posn) {
 		super(isPrivate, isStatic, t, name, posn);
 	}
 
@@ -21,4 +22,3 @@ public class FieldDecl extends MemberDecl {
 		return v.visitFieldDecl(this, o);
 	}
 }
-

miniJava/src/miniJava/AbstractSyntaxTrees/FieldDeclList.java

@@ -7,8 +7,7 @@ package miniJava.AbstractSyntaxTrees;
 
 import java.util.*;
 
-public class FieldDeclList implements Iterable<FieldDecl>
+public class FieldDeclList implements Iterable<FieldDecl> {
-{
 	public FieldDeclList() {
 		fieldDeclList = new ArrayList<FieldDecl>();
 	}
@@ -36,4 +35,3 @@ public class FieldDeclList implements Iterable<FieldDecl>
 
 	private List<FieldDecl> fieldDeclList;
 }
-

miniJava/src/miniJava/AbstractSyntaxTrees/IfStmt.java

@@ -7,8 +7,7 @@ package miniJava.AbstractSyntaxTrees;
 
 import miniJava.SyntacticAnalyzer.SourcePosition;
 
-public class IfStmt extends Statement
+public class IfStmt extends Statement {
-{
 	public IfStmt(Expression b, Statement t, Statement e, SourcePosition posn) {
 		super(posn);
 		cond = b;

miniJava/src/miniJava/AbstractSyntaxTrees/LiteralExpr.java

@@ -7,8 +7,7 @@ package miniJava.AbstractSyntaxTrees;
 
 import miniJava.SyntacticAnalyzer.SourcePosition;
 
-public class LiteralExpr extends Expression
+public class LiteralExpr extends Expression {
-{
 	public LiteralExpr(Literal c, SourcePosition posn) {
 		super(posn);
 		literal = c;

miniJava/src/miniJava/AbstractSyntaxTrees/MemberDecl.java

@@ -9,7 +9,8 @@ import miniJava.SyntacticAnalyzer.SourcePosition;
 
 abstract public class MemberDecl extends Declaration {
 
-    public MemberDecl(boolean isPrivate, boolean isStatic, Type mt, String name, SourcePosition posn) {
+	public MemberDecl(boolean isPrivate, boolean isStatic, Type mt,
+			String name, SourcePosition posn) {
 		super(name, mt, posn);
 		this.isPrivate = isPrivate;
 		this.isStatic = isStatic;

miniJava/src/miniJava/AbstractSyntaxTrees/MethodDecl.java

@@ -9,7 +9,8 @@ import miniJava.SyntacticAnalyzer.SourcePosition;
 
 public class MethodDecl extends MemberDecl {
 
-	public MethodDecl(MemberDecl md, ParameterDeclList pl, StatementList sl, Expression e, SourcePosition posn){
+	public MethodDecl(MemberDecl md, ParameterDeclList pl, StatementList sl,
+			Expression e, SourcePosition posn) {
 		super(md, posn);
 		parameterDeclList = pl;
 		statementList = sl;

miniJava/src/miniJava/AbstractSyntaxTrees/MethodDeclList.java

@@ -7,8 +7,7 @@ package miniJava.AbstractSyntaxTrees;
 
 import java.util.*;
 
-public class MethodDeclList implements Iterable<MethodDecl>
+public class MethodDeclList implements Iterable<MethodDecl> {
-{
 	public MethodDeclList() {
 		methodDeclList = new ArrayList<MethodDecl>();
 	}
@@ -36,4 +35,3 @@ public class MethodDeclList implements Iterable<MethodDecl>
 
 	private List<MethodDecl> methodDeclList;
 }
-

miniJava/src/miniJava/AbstractSyntaxTrees/NewArrayExpr.java

@@ -7,8 +7,7 @@ package miniJava.AbstractSyntaxTrees;
 
 import miniJava.SyntacticAnalyzer.SourcePosition;
 
-public class NewArrayExpr extends NewExpr
+public class NewArrayExpr extends NewExpr {
-{
 	public NewArrayExpr(Type et, Expression e, SourcePosition posn) {
 		super(posn);
 		eltType = et;

miniJava/src/miniJava/AbstractSyntaxTrees/NewObjectExpr.java

@@ -7,8 +7,7 @@ package miniJava.AbstractSyntaxTrees;
 
 import miniJava.SyntacticAnalyzer.SourcePosition;
 
-public class NewObjectExpr extends NewExpr
+public class NewObjectExpr extends NewExpr {
-{
 	public NewObjectExpr(ClassType ct, SourcePosition posn) {
 		super(posn);
 		classtype = ct;

miniJava/src/miniJava/AbstractSyntaxTrees/Operator.java

@@ -12,6 +12,7 @@ public class Operator extends Terminal {
 
 	public Operator(Token t, SourcePosition posn) {
 		super(t.spelling, posn);
+		token = t;
 	}
 
 	public <A, R> R visit(Visitor<A, R> v, A o) {

miniJava/src/miniJava/AbstractSyntaxTrees/ParameterDecl.java

@@ -17,4 +17,3 @@ public class ParameterDecl extends LocalDecl {
 		return v.visitParameterDecl(this, o);
 	}
 }
-

miniJava/src/miniJava/AbstractSyntaxTrees/ParameterDeclList.java

@@ -7,8 +7,7 @@ package miniJava.AbstractSyntaxTrees;
 
 import java.util.*;
 
-public class ParameterDeclList implements Iterable<ParameterDecl>
+public class ParameterDeclList implements Iterable<ParameterDecl> {
-{
 	public ParameterDeclList() {
 		parameterDeclList = new ArrayList<ParameterDecl>();
 	}

miniJava/src/miniJava/AbstractSyntaxTrees/RefExpr.java

@@ -7,8 +7,7 @@ package miniJava.AbstractSyntaxTrees;
 
 import miniJava.SyntacticAnalyzer.SourcePosition;
 
-public class RefExpr extends Expression
+public class RefExpr extends Expression {
-{
 	public RefExpr(Reference r, SourcePosition posn) {
 		super(posn);
 		ref = r;

miniJava/src/miniJava/AbstractSyntaxTrees/Reference.java

@@ -7,8 +7,7 @@ package miniJava.AbstractSyntaxTrees;
 
 import miniJava.SyntacticAnalyzer.SourcePosition;
 
-public abstract class Reference extends AST
+public abstract class Reference extends AST {
-{
 	public Reference(SourcePosition posn) {
 		super(posn);
 	}

miniJava/src/miniJava/AbstractSyntaxTrees/StatementList.java

@@ -7,8 +7,7 @@ package miniJava.AbstractSyntaxTrees;
 
 import java.util.*;
 
-public class StatementList implements Iterable<Statement>
+public class StatementList implements Iterable<Statement> {
-{
 	public StatementList() {
 		slist = new ArrayList<Statement>();
 	}

miniJava/src/miniJava/AbstractSyntaxTrees/Type.java

@@ -17,5 +17,3 @@ abstract public class Type extends AST {
 	public TypeKind typeKind;
 
 }
-
-        

miniJava/src/miniJava/AbstractSyntaxTrees/TypeKind.java

@@ -6,12 +6,5 @@
 package miniJava.AbstractSyntaxTrees;
 
 public enum TypeKind {
-        VOID,
+	VOID, INT, BOOLEAN, CLASS, ARRAY, UNSUPPORTED, ERROR, EQUALS, RELATIONAL;
-		INT,
-        BOOLEAN,
-        CLASS,
-        ARRAY,
-        UNSUPPORTED,
-        ERROR,
-        VALID;
 }

miniJava/src/miniJava/AbstractSyntaxTrees/UnaryExpr.java

@@ -7,8 +7,7 @@ package miniJava.AbstractSyntaxTrees;
 
 import miniJava.SyntacticAnalyzer.SourcePosition;
 
-public class UnaryExpr extends Expression
+public class UnaryExpr extends Expression {
-{
 	public UnaryExpr(Operator o, Expression e, SourcePosition posn) {
 		super(posn);
 		operator = o;

miniJava/src/miniJava/AbstractSyntaxTrees/VarDeclStmt.java

@@ -7,8 +7,7 @@ package miniJava.AbstractSyntaxTrees;
 
 import miniJava.SyntacticAnalyzer.SourcePosition;
 
-public class VarDeclStmt extends Statement
+public class VarDeclStmt extends Statement {
-{
 	public VarDeclStmt(VarDecl vd, Expression e, SourcePosition posn) {
 		super(posn);
 		varDecl = vd;

miniJava/src/miniJava/AbstractSyntaxTrees/Visitor.java

@@ -6,8 +6,8 @@
 package miniJava.AbstractSyntaxTrees;
 
 /**
- * An implementation of the Visitor interface provides a method visitX
+ * An implementation of the Visitor interface provides a method visitX for each
- * for each non-abstract AST class X.  
+ * non-abstract AST class X.
  */
 public interface Visitor<ArgType, ResultType> {
 
@@ -16,42 +16,65 @@ public interface Visitor<ArgType,ResultType> {
 
 	// Declarations
 	public ResultType visitClassDecl(ClassDecl cd, ArgType arg);
+
 	public ResultType visitFieldDecl(FieldDecl fd, ArgType arg);
+
 	public ResultType visitMethodDecl(MethodDecl md, ArgType arg);
+
 	public ResultType visitParameterDecl(ParameterDecl pd, ArgType arg);
+
 	public ResultType visitVarDecl(VarDecl decl, ArgType arg);
 
 	// Types
 	public ResultType visitBaseType(BaseType type, ArgType arg);
+
 	public ResultType visitClassType(ClassType type, ArgType arg);
+
 	public ResultType visitArrayType(ArrayType type, ArgType arg);
 
 	// Statements
 	public ResultType visitBlockStmt(BlockStmt stmt, ArgType arg);
+
 	public ResultType visitVardeclStmt(VarDeclStmt stmt, ArgType arg);
+
 	public ResultType visitAssignStmt(AssignStmt stmt, ArgType arg);
+
 	public ResultType visitCallStmt(CallStmt stmt, ArgType arg);
+
 	public ResultType visitIfStmt(IfStmt stmt, ArgType arg);
+
 	public ResultType visitWhileStmt(WhileStmt stmt, ArgType arg);
 
 	// Expressions
 	public ResultType visitUnaryExpr(UnaryExpr expr, ArgType arg);
+
 	public ResultType visitBinaryExpr(BinaryExpr expr, ArgType arg);
+
 	public ResultType visitRefExpr(RefExpr expr, ArgType arg);
+
 	public ResultType visitCallExpr(CallExpr expr, ArgType arg);
+
 	public ResultType visitLiteralExpr(LiteralExpr expr, ArgType arg);
+
 	public ResultType visitNewObjectExpr(NewObjectExpr expr, ArgType arg);
+
 	public ResultType visitNewArrayExpr(NewArrayExpr expr, ArgType arg);
 
 	// References
 	public ResultType visitQualifiedRef(QualifiedRef ref, ArgType arg);
+
 	public ResultType visitIndexedRef(IndexedRef ref, ArgType arg);
+
 	public ResultType visitIdRef(IdRef ref, ArgType arg);
+
 	public ResultType visitThisRef(ThisRef ref, ArgType arg);
 
 	// Terminals
 	public ResultType visitIdentifier(Identifier id, ArgType arg);
+
 	public ResultType visitOperator(Operator op, ArgType arg);
+
 	public ResultType visitIntLiteral(IntLiteral num, ArgType arg);
+
 	public ResultType visitBooleanLiteral(BooleanLiteral bool, ArgType arg);
 }

miniJava/src/miniJava/AbstractSyntaxTrees/WhileStmt.java

@@ -7,8 +7,7 @@ package miniJava.AbstractSyntaxTrees;
 
 import miniJava.SyntacticAnalyzer.SourcePosition;
 
-public class WhileStmt extends Statement
+public class WhileStmt extends Statement {
-{
 	public WhileStmt(Expression b, Statement s, SourcePosition posn) {
 		super(posn);
 		cond = b;

miniJava/src/miniJava/Compiler.java

@@ -3,15 +3,14 @@ package miniJava;
 import java.io.*;
 
 import miniJava.SyntacticAnalyzer.*;
-import miniJava.AbstractSyntaxTrees.ASTDisplay;
+// import miniJava.AbstractSyntaxTrees.ASTDisplay;
 import miniJava.AbstractSyntaxTrees.Package;
 import miniJava.ContextualAnalyzer.Analyzer;
-import miniJava.ContextualAnalyzer.Reporter;
 import miniJava.Exceptions.*;
 
 public class Compiler {
 
-	private static final int rc = 4;
+	public static final int rc = 4;
 
 	public static void main(String[] args) {
 
@@ -34,9 +33,7 @@ public class Compiler {
 			// Identification/Type Checking
 			Analyzer analyzer = new Analyzer();
 			analyzer.visitPackage(p, null);
-			if(Reporter.error) System.exit(rc);
+			System.exit(analyzer.validate());
-			
-			System.exit(0);
 
 		} catch (FileNotFoundException e) {
 			System.out.println("***" + e.getMessage());

miniJava/src/miniJava/ContextualAnalyzer/Analyzer.java

@@ -1,93 +1,76 @@
 package miniJava.ContextualAnalyzer;
 
+import java.util.*;
+
+import miniJava.Compiler;
+import miniJava.Exceptions.*;
+import miniJava.SyntacticAnalyzer.*;
+import miniJava.SyntacticAnalyzer.Scanner;
 import miniJava.AbstractSyntaxTrees.*;
 import miniJava.AbstractSyntaxTrees.Package;
-import miniJava.SyntacticAnalyzer.Parser;
-import miniJava.SyntacticAnalyzer.Scanner;
-import miniJava.Exceptions.*;
 
-// Check types
-// Ensure static members
-// Check for main function
 public class Analyzer implements Visitor<IdentificationTable, Type> {
 
-	// Topmost Identification Table
+	private MethodDecl mainMethod = null;
+	private ClassDecl currentClassDecl = null;
+	private MethodDecl currentMethodDecl = null;
 	private IdentificationTable table = new IdentificationTable();
 
-	// Current class decl is for use with the 'this' keyword
+	// Keep track of all predefined names to handle
-	private Declaration currentClassDecl = null;
+	private static ArrayList<String> predefined;
+	static 
+	{
+		predefined = new ArrayList<String>();
+		predefined.add("class _PrintStream { public void println(int n){} }");
+		predefined.add("class System {  public static _PrintStream out; }");
+		predefined.add("class String { }");
+	}
 
 	/**
-	 * Adds predefined names to identification table.
+	 * Adds predefined names to topmost table. These names should not be allowed
+	 * redefinition and must be ordered such that no class refers to one
+	 * undeclared yet.
 	 */
-	public Analyzer() {		
+	public Analyzer() throws ParsingException, ScanningException {
-		try {			
+		for (String s : predefined) {
-			String __PrintStream = "class _PrintStream { public void println(int n){} }";
+			Scanner scanner = new Scanner(s);
-			new Parser(new Scanner(__PrintStream)).parse().visit(this, table);
+			Parser parser = new Parser(scanner);
-			
+			parser.parse().visit(this, table);
-			String _System = "class System {  public static _PrintStream out; }";
-			new Parser(new Scanner(_System)).parse().visit(this, table);
-			
-			String _String = "class String { }";
-			new Parser(new Scanner(_String)).parse().visit(this, table);
-			
-		} catch(ParsingException e) {
-			System.out.println("Predefined declarations parsing error!");
-		} catch(ScanningException e) {
-			System.out.println("Predefined declarations scanning error!");
 		}
 	}
 
 	/**
-	 * Check that two types match.
+	 * Checks that contextual analysis was successful or not, returning the
-	 * @param t1
+	 * proper error code in either case.
-	 * @param t2
+	 * 
 	 * @return
 	 */
-	private void match(Type t1, Type t2) {
+	public int validate() {
+		// Exactly one public static void main(String[] args) function must be declared
+		if (mainMethod == null)
+			Reporter.report(ErrorType.MAIN_UNDECLARED, null, null);
 
-		// Check class types match
+		return (Reporter.error) ? Compiler.rc : 0;
-		if(t1.typeKind == TypeKind.CLASS) {
-			if(t2.typeKind != TypeKind.CLASS) {
-				Reporter.report(ErrorType.TYPE_MISMATCH, t1, t2);
-			} else {
-				ClassType c1 = (ClassType) t1;
-				ClassType c2 = (ClassType) t2;
-				if(!c1.className.spelling.equals(c2.className.spelling)) {
-					Reporter.report(ErrorType.TYPE_CLASS_MISMATCH, t1, t2);
-				}
-			}
 	}
 
-		// Check array types match
-		else if(t1.typeKind == TypeKind.ARRAY) {
-			if(t2.typeKind != TypeKind.ARRAY) {
-				Reporter.report(ErrorType.TYPE_MISMATCH, t1, t2);
-			} else {
-				ArrayType a1 = (ArrayType) t1;
-				ArrayType a2 = (ArrayType) t2;
-				if(a1.eltType.typeKind != a2.eltType.typeKind) {
-					Reporter.report(ErrorType.TYPE_ARRAY_MISMATCH, t1, t2);
-				}
-			}
-		}
 	
-		// Check primitive types match
+	// /////////////////////////////////////////////////////////////////////////////
-		else if(t1.typeKind != t2.typeKind) {
+	//
-			Reporter.report(ErrorType.TYPE_MISMATCH, t1, t2);
+	// PACKAGE
-		}
+	//
-	}
+	// /////////////////////////////////////////////////////////////////////////////
 
-	@Override
 	public Type visitPackage(Package prog, IdentificationTable arg) {
 
-		/* Since classes and static methods/fields can be referenced
+		/*
-		 * before the classes themselves are declared, we preprocess
+		 * Since classes and static methods/fields can be referenced before the
-		 * all classes and methods first.
+		 * classes themselves are declared, we preprocess all classes and
+		 * methods first.
 		 */
 		for (ClassDecl cd : prog.classDeclList) {
 
 			IdentificationTable cdTable = table.openScope(cd);
+
 			if (cdTable != null) {
 
 				// Simply add fields to current scope
@@ -111,9 +94,17 @@ public class Analyzer implements Visitor<IdentificationTable, Type> {
 		return null;
 	}
 
-	@Override
+	
+	// /////////////////////////////////////////////////////////////////////////////
+	//
+	// DECLARATIONS
+	//
+	// /////////////////////////////////////////////////////////////////////////////
+
 	public Type visitClassDecl(ClassDecl cd, IdentificationTable arg) {
+
 		IdentificationTable cdTable = arg.getScope(cd);
+
 		if (cdTable != null) {
 
 			for (FieldDecl fd : cd.fieldDeclList) {
@@ -121,6 +112,7 @@ public class Analyzer implements Visitor<IdentificationTable, Type> {
 			}
 
 			for (MethodDecl md : cd.methodDeclList) {
+				currentMethodDecl = md;
 				md.visit(this, cdTable);
 			}
 		}
@@ -128,142 +120,158 @@ public class Analyzer implements Visitor<IdentificationTable, Type> {
 		return cd.type;
 	}
 
-	@Override
 	public Type visitFieldDecl(FieldDecl fd, IdentificationTable arg) {
 
 		// Must check that the type of the field can be identified
-		table.validateClassId(fd.type);
+		if (!table.classExists(fd.type)) {
+			Reporter.report(ErrorType.UNDECLARED_TYPE, fd.type, null);
+		}
 
 		return fd.type;
 	}
 
-	@Override
 	public Type visitMethodDecl(MethodDecl md, IdentificationTable arg) {
 
-		IdentificationTable mdTable = arg.getScope(md);
+		// Check if a valid entry point to program
+		if (IdentificationTable.isMainMethod(md)) {
+			if (mainMethod != null)
+				Reporter.report(ErrorType.MULTIPLE_MAIN, md, mainMethod);
+			else
+				mainMethod = md;
+		}
 
 		// Must check that the type of the method can be identified
-		table.validateClassId(md.type);
+		if (!table.classExists(md.type)) {
+			Reporter.report(ErrorType.UNDECLARED_TYPE, md.type, null);
+		}
 
 		// Continue Traversal
+		IdentificationTable mdTable = arg.getScope(md);
 		if (mdTable != null) {
-			for(ParameterDecl pd : md.parameterDeclList) {
+			for (ParameterDecl pd : md.parameterDeclList)
 				pd.visit(this, mdTable);
-			}
+			for (Statement s : md.statementList)
-			
-			for(Statement s : md.statementList) {
 				s.visit(this, mdTable);
-			}
 
 			// Check that return type matches expected type
-			if(md.returnExp != null) {
+			if (md.returnExp == null && md.type.typeKind != TypeKind.VOID) {
+				Reporter.report(ErrorType.NO_RETURN, md, null);
+			} else if (md.returnExp != null) {
 				Type returnType = md.returnExp.visit(this, mdTable);
-				match(md.type, returnType);
+				IdentificationTable.match(md.type, returnType, true);
-			} else if(md.type.typeKind != TypeKind.VOID) {
-				Reporter.report(ErrorType.NO_RETURN_EXPRESSION, md.type);
 			}
 		}
 
 		return md.type;
 	}
 
-	@Override
 	public Type visitParameterDecl(ParameterDecl pd, IdentificationTable arg) {
 		arg.setDeclarationAtScope(pd);
-		table.validateClassId(pd.type);
+		if (!table.classExists(pd.type)) {
+			Reporter.report(ErrorType.UNDECLARED_TYPE, pd.type, null);
+		}
+
 		return pd.type;
 	}
 
-	@Override
 	public Type visitVarDecl(VarDecl decl, IdentificationTable arg) {
 		arg.setDeclarationAtScope(decl);
-		table.validateClassId(decl.type);
+		if (!table.classExists(decl.type)) {
+			Reporter.report(ErrorType.UNDECLARED_TYPE, decl.type, null);
+		}
+
 		return decl.type;
 	}
 	
-	@Override
+
+	// /////////////////////////////////////////////////////////////////////////////
+	//
+	// TYPES
+	//
+	// /////////////////////////////////////////////////////////////////////////////
+
 	public Type visitBaseType(BaseType type, IdentificationTable arg) {
 
 		return type;
 	}
 
-	@Override
 	public Type visitClassType(ClassType type, IdentificationTable arg) {
 		type.className.visit(this, arg);
 		return type;
 	}
 
-	@Override
 	public Type visitArrayType(ArrayType type, IdentificationTable arg) {
 		type.eltType.visit(this, arg);
 		return type;
 	}
 	
-	@Override
+
+	// /////////////////////////////////////////////////////////////////////////////
+	//
+	// STATEMENTS
+	//
+	// /////////////////////////////////////////////////////////////////////////////
+
 	public Type visitBlockStmt(BlockStmt stmt, IdentificationTable arg) {
 		arg.pushLevel();
-		for(Statement s : stmt.sl) {
+		for (Statement s : stmt.sl)
 			s.visit(this, arg);
-		}
 		arg.popLevel();
 
 		return null;
 	}
 
-	@Override
-	public Type visitVardeclStmt(VarDeclStmt stmt, IdentificationTable arg) {
-		
 	// The stmt of the vardecl may not refer to the variable itself so we check the stmt first
+	public Type visitVardeclStmt(VarDeclStmt stmt, IdentificationTable arg) {
 		Type initExpType = stmt.initExp.visit(this, arg);
 		Type varDeclType = stmt.varDecl.visit(this, arg);
-		match(varDeclType, initExpType);
+		IdentificationTable.match(varDeclType, initExpType, true);
 
 		return varDeclType;
 	}
 
-	@Override
 	public Type visitAssignStmt(AssignStmt stmt, IdentificationTable arg) {
 		Type valType = stmt.val.visit(this, arg);
 		Type refType = stmt.ref.visit(this, arg);
-		match(valType, refType);
+		IdentificationTable.match(valType, refType, true);
 
 		return refType;
 	}
 
-	@Override
 	public Type visitCallStmt(CallStmt stmt, IdentificationTable arg) {
+
 		Type methodType = stmt.methodRef.visit(this, arg);
 
 		// Check that parameter count is correct and each type is correct
 		MethodDecl decl = (MethodDecl) stmt.methodRef.decl;
 		if (decl.parameterDeclList.size() != stmt.argList.size()) {
-			Reporter.report(ErrorType.INVALID_PARAM_COUNT, stmt);
+			Reporter.report(ErrorType.INVALID_PARAM_COUNT, stmt, decl);
 		} else {
 			for (int i = 0; i < stmt.argList.size(); i++) {
 				Type exprType = stmt.argList.get(i).visit(this, arg);
 				Type pdType = decl.parameterDeclList.get(i).type;
-				match(pdType, exprType);
+				IdentificationTable.match(pdType, exprType, true);
 			}
 		}
 
 		return methodType;
 	}
 
-	@Override
 	public Type visitIfStmt(IfStmt stmt, IdentificationTable arg) {
 
 		// The conditional statment must be a boolean
 		Type condType = stmt.cond.visit(this, arg);
-		match(new BaseType(TypeKind.BOOLEAN, null), condType);
+		IdentificationTable.match(new BaseType(TypeKind.BOOLEAN, null), condType, true);
 
 		// A single vardecl cannot exist after a conditional statement
 		if (stmt.thenStmt instanceof VarDeclStmt) {
-			Reporter.report(ErrorType.VAR_COND_ONLY, stmt.thenStmt);
+			Reporter.report(ErrorType.SINGLE_VARCOND, stmt.thenStmt, null);
 		} else {
 			stmt.thenStmt.visit(this, arg);
 			if (stmt.elseStmt != null) {
 				if (stmt.elseStmt instanceof VarDeclStmt) {
-					Reporter.report(ErrorType.VAR_COND_ONLY, stmt.elseStmt);
+					Reporter.report(ErrorType.SINGLE_VARCOND, stmt.elseStmt,
+							null);
 				} else {
 					stmt.elseStmt.visit(this, arg);
 				}
@@ -273,15 +281,15 @@ public class Analyzer implements Visitor<IdentificationTable, Type> {
 		return null;
 	}
 
-	@Override
 	public Type visitWhileStmt(WhileStmt stmt, IdentificationTable arg) {
 
 		// The conditional statment must be a boolean
 		Type condType = stmt.cond.visit(this, arg);
-		match(new BaseType(TypeKind.BOOLEAN, null), condType);
+		IdentificationTable.match(new BaseType(TypeKind.BOOLEAN, null), condType, true);
 
+		// A single vardecl cannot exist after a conditional statement
 		if (stmt.body instanceof VarDeclStmt) {
-			Reporter.report(ErrorType.VAR_COND_ONLY, stmt.body);
+			Reporter.report(ErrorType.SINGLE_VARCOND, stmt.body, null);
 		} else {
 			stmt.body.visit(this, arg);
 		}
@@ -289,164 +297,270 @@ public class Analyzer implements Visitor<IdentificationTable, Type> {
 		return null;
 	}
 
-	@Override
+	
+	// /////////////////////////////////////////////////////////////////////////////
+	//
+	// EXPRESSIONS
+	//
+	// /////////////////////////////////////////////////////////////////////////////
+
 	public Type visitUnaryExpr(UnaryExpr expr, IdentificationTable arg) {
 		Type opType = expr.operator.visit(this, arg);
 		Type exprType = expr.expr.visit(this, arg);
-		match(opType, exprType);
+		IdentificationTable.match(opType, exprType, true);
 
-		return null;
+		return opType;
 	}
 
-	@Override
 	public Type visitBinaryExpr(BinaryExpr expr, IdentificationTable arg) {
 		Type opType = expr.operator.visit(this, arg);
 		Type leftType = expr.left.visit(this, arg);
 		Type rightType = expr.right.visit(this, arg);
 		
-		match(opType, leftType);
+		// Both sides must be the same
-		match(opType, rightType);
+		if(opType.typeKind == TypeKind.EQUALS) {
-		
+			IdentificationTable.match(leftType, rightType, true);
-		return null;
+			return new BaseType(TypeKind.BOOLEAN, opType.posn);
+		} 
+		
+		// Both sides must be integers
+		else if(opType.typeKind == TypeKind.RELATIONAL) {
+			BaseType bt = new BaseType(TypeKind.INT, opType.posn);
+			IdentificationTable.match(bt, leftType, true);
+			IdentificationTable.match(bt, rightType, true);
+			return new BaseType(TypeKind.BOOLEAN, opType.posn);
+		} 
+		
+		// Both sides must match operator type
+		IdentificationTable.match(leftType, opType, true);
+		IdentificationTable.match(rightType, opType, true);
+		return opType;
 	}
 
-	@Override
 	public Type visitRefExpr(RefExpr expr, IdentificationTable arg) {
-		
+		Type exprType = expr.ref.visit(this, arg);
-		return expr.ref.visit(this, arg);
+		return exprType;
 	}
 
-	@Override
 	public Type visitCallExpr(CallExpr expr, IdentificationTable arg) {
-		Type functionType = expr.functionRef.visit(this, arg);
+		Type functionRefType = expr.functionRef.visit(this, arg);
+		
+		if(expr.functionRef.decl instanceof MethodDecl) {
+			
+			MethodDecl decl = (MethodDecl) expr.functionRef.decl;
 			
 			// Check that parameter count is correct and each type is correct
-		MethodDecl decl = (MethodDecl) expr.functionRef.decl;
 			if (decl.parameterDeclList.size() != expr.argList.size()) {
-			Reporter.report(ErrorType.INVALID_PARAM_COUNT, expr);
+				Reporter.report(ErrorType.INVALID_PARAM_COUNT, expr, decl);
 			} else {
 				for (int i = 0; i < expr.argList.size(); i++) {
 					Type exprType = expr.argList.get(i).visit(this, arg);
 					Type pdType = decl.parameterDeclList.get(i).type;
-				match(pdType, exprType);
+					IdentificationTable.match(pdType, exprType, true);
 				}
 			}
+		} else {
+			Reporter.report(ErrorType.NONFUNCTION_CALL, expr, null);
+		}
 
-		return functionType;
+		return functionRefType;
 	}
 
-	@Override
 	public Type visitLiteralExpr(LiteralExpr expr, IdentificationTable arg) {
-		
+		Type literalType = expr.literal.visit(this, arg);
-		return expr.literal.visit(this, arg);
+		return literalType;
 	}
 
-	@Override
 	public Type visitNewObjectExpr(NewObjectExpr expr, IdentificationTable arg) {
-		
+		Type objectType = expr.classtype.visit(this, arg);
-		return expr.classtype.visit(this, arg);
+		return objectType;
 	}
 
-	@Override
 	public Type visitNewArrayExpr(NewArrayExpr expr, IdentificationTable arg) {
 		Type sizeExprType = expr.sizeExpr.visit(this, arg);
 		if (sizeExprType.typeKind != TypeKind.INT) {
-			Reporter.report(ErrorType.INVALID_INDEX, expr.sizeExpr);
+			Reporter.report(ErrorType.INVALID_INDEX, expr.sizeExpr, null);
 		}
 
-		return expr.eltType.visit(this, arg);
+		Type eltType = expr.eltType.visit(this, arg);
+		return new ArrayType(eltType, expr.posn);
 	}
 
-	@Override
+	
+	// /////////////////////////////////////////////////////////////////////////////
+	//
+	// REFERENCES
+	//
+	// /////////////////////////////////////////////////////////////////////////////
+
 	public Type visitQualifiedRef(QualifiedRef ref, IdentificationTable arg) {
-		ref.ref.visit(this, arg);
-		ref.id.visit(this, arg);
 		
-		// Check that each declaration is nested properly
+		Type refType = ref.ref.visit(this, arg);
-		if(ref.decl == null || table.getDeclaration(ref.decl.name) == null) {
+		
-			System.out.println(ref.id.spelling);
+		// Note qualified ref's only make sense in the context of classes
-			// report(ErrorType.MISSING_DECL, ref.ref.decl);
+		if(refType.typeKind != TypeKind.CLASS) {
+			if(refType.typeKind != TypeKind.ERROR) // Don't need to report multiple times
+				Reporter.report(ErrorType.TYPE_MISMATCH, new BaseType(TypeKind.CLASS, null), refType);
+			
+			return refType;
 		} 
 		
-		return null;
+		// Try to find qualified member
+		Declaration qualified = ref.ref.decl;
+		ClassType qualType = (ClassType) qualified.type;
+		Declaration qualClassDecl = table.getDeclaration(qualType.className.spelling);
+		if(qualClassDecl == null) {
+			Reporter.report(ErrorType.UNDECLARED_TYPE, qualified.type, null);
+			return new BaseType(TypeKind.ERROR, qualified.posn);
+		}
+		
+		// Get member
+		IdentificationTable cdTable = table.getScope(qualClassDecl);
+		MemberDecl md = (MemberDecl) cdTable.getDeclarationAtScope(ref.id.spelling);
+				
+		// Check the member exists at all
+		if(md == null) {
+			Reporter.report(ErrorType.UNDEFINED, ref.id, null);
+			return new BaseType(TypeKind.ERROR, ref.id.posn);
+		}
+				
+		// If the qualifed ref is a class declaration, members must be static
+		else if(qualified instanceof ClassDecl) {
+			if(!md.isStatic) {
+				Reporter.report(ErrorType.STATIC, md, ref.id);
+				return new BaseType(TypeKind.ERROR, ref.id.posn);
+			} else if(md.isPrivate) {
+				Reporter.report(ErrorType.VISIBILITY, md, ref.id);
+				return new BaseType(TypeKind.ERROR, ref.id.posn);
+			}
+		}
+		
+		// The member should not be a method, as this is unsupported
+		else if(qualified instanceof MethodDecl) {
+			Reporter.report(ErrorType.UNDEFINED, ref.id, null);
+		}
+				
+		// Otherwise, we can assume the object is a variable and attempt to access members
+		else if(md.isPrivate && currentClassDecl != qualClassDecl) {
+			Reporter.report(ErrorType.VISIBILITY, md, ref.id);
+			return new BaseType(TypeKind.ERROR, ref.id.posn);
+		}
+		
+		ref.id.decl = md;
+		ref.decl = md;
+		return md.type;
 	}
 
-	@Override
 	public Type visitIndexedRef(IndexedRef ref, IdentificationTable arg) {
-		ref.ref.visit(this, arg);
+				
-		ref.decl = ref.ref.decl;
+		Type refType = ref.ref.visit(this, arg);
 
 		// Make sure index is an integer
 		Type indexExprType = ref.indexExpr.visit(this, arg);
 		if (indexExprType.typeKind != TypeKind.INT) {
-			Reporter.report(ErrorType.INVALID_INDEX, ref.indexExpr);
+			Reporter.report(ErrorType.INVALID_INDEX, ref.indexExpr, null);
 		}
 
-		return ref.decl.type;
+		ref.decl = ref.ref.decl;
+		return refType;
 	}
 
-	@Override
 	public Type visitIdRef(IdRef ref, IdentificationTable arg) {
-		ref.id.visit(this, arg);
+		Type idType = ref.id.visit(this, arg);
 		ref.decl = ref.id.decl;
 
-		return ref.decl.type;
+		return idType;
 	}
 
-	@Override
 	public Type visitThisRef(ThisRef ref, IdentificationTable arg) {
 		ref.decl = currentClassDecl;
+		if(currentMethodDecl.isStatic) {
+			Reporter.report(ErrorType.THIS, ref, currentMethodDecl);
+		}
 		
 		return ref.decl.type;
 	}
 	
-	@Override
+
+	// /////////////////////////////////////////////////////////////////////////////
+	//
+	// TERMINALS
+	//
+	// /////////////////////////////////////////////////////////////////////////////
+
 	public Type visitIdentifier(Identifier id, IdentificationTable arg) {
-		// Try to find identifier, reporting a message if it cannot be found
+
-		Declaration decl = arg.getDeclaration(id.spelling);
+		// Check if identifier can be found in current scope
-		if(decl == null) {
+		Declaration decl = arg.getDeclarationAtScope(id.spelling);
-			Reporter.report(ErrorType.UNIDENTIFIED, id);
+		if (decl != null) { id.decl = decl; return decl.type; }
-			return new BaseType(TypeKind.ERROR, null);
+		
+		// Access member and check visibility properties
+		Declaration d = arg.getDeclaration(id.spelling);
+		if(d == null) {
+			Reporter.report(ErrorType.UNDEFINED, id, null);
+			return new BaseType(TypeKind.ERROR, id.posn);
 		} else {
-			id.decl = decl;
+			
-			return decl.type;
+			// Can only be a member at this point
+			if(d.type.typeKind != TypeKind.CLASS) {
+				MemberDecl md = (MemberDecl) d;
+				
+				// A static method cannot access instance members
+				if(currentMethodDecl.isStatic && !md.isStatic) {
+					Reporter.report(ErrorType.STATIC, md, id);
+					return new BaseType(TypeKind.ERROR, id.posn);
+				}
+				
+				// If a member declaration is private, it must be a member of the current class
+				else if(md.isPrivate) {
+					
+					// Check if member is part of the current class
+					IdentificationTable cdTable = table.getScope(currentClassDecl);
+					if(cdTable.getDeclarationAtScope(md.name) == null) {
+						Reporter.report(ErrorType.VISIBILITY, md, id);
+						return new BaseType(TypeKind.ERROR, id.posn);
+					}
+				}
+			}
+			
+			id.decl = d;
+			return d.type;
 		}
 	}
 
-	@Override
 	public Type visitOperator(Operator op, IdentificationTable arg) {
 		
 		switch (op.token.spelling) {
 			case "!":
-			case ">":
-			case "<":
-			case "==":
-			case "<=":
-			case ">=":
-			case "!=":
 			case "&&":
 			case "||":
 				return new BaseType(TypeKind.BOOLEAN, op.posn);
 				
+			case ">":
+			case "<":
+			case "<=":
+			case ">=":
+				return new BaseType(TypeKind.RELATIONAL, op.posn);
+				
 			case "+":
 			case "-":
 			case "*":
 			case "/":
 				return new BaseType(TypeKind.INT, op.posn);
 				
-			default:
+			case "==":
-				Reporter.report(ErrorType.UNIDENTIFIED_TYPE, op);
+			case "!=":
-				return new BaseType(TypeKind.ERROR, op.posn);
+				return new BaseType(TypeKind.EQUALS, op.posn);
-		}
+		}
+
+		return null;
 	}
 
-	@Override
 	public Type visitIntLiteral(IntLiteral num, IdentificationTable arg) {
 
 		return new BaseType(TypeKind.INT, num.posn);
 	}
 
-	@Override
 	public Type visitBooleanLiteral(BooleanLiteral bool, IdentificationTable arg) {
 
 		return new BaseType(TypeKind.BOOLEAN, bool.posn);

miniJava/src/miniJava/ContextualAnalyzer/IdentificationTable.java

@@ -1,12 +1,8 @@
 package miniJava.ContextualAnalyzer;
 
-import java.util.HashMap;
+import java.util.*;
-import java.util.ArrayList;
 
-import miniJava.AbstractSyntaxTrees.ClassType;
+import miniJava.AbstractSyntaxTrees.*;
-import miniJava.AbstractSyntaxTrees.Declaration;
-import miniJava.AbstractSyntaxTrees.Type;
-import miniJava.AbstractSyntaxTrees.TypeKind;
 
 public class IdentificationTable {
 
@@ -33,29 +29,29 @@ public class IdentificationTable {
 	}
 
 	/**
-	 * Adds another level for variables to be stored at (they will be 
+	 * Adds another level for variables to be stored at
-	 * removed when popping said level).
-	 */
-	public void pushLevel() {
-		table.add(new HashMap<String, Declaration>());
-	}
-	
-	/**
-	 * Removes all variables declared at the current level (these are
-	 * no longer accessible).
 	 */
 	public void popLevel() {
 		table.remove(table.size() - 1);
 	}
 
 	/**
-	 * This method will only ever be called with class/method declarations
+	 * Removes all variables declared at the current level
+	 */
+	public void pushLevel() {
+		table.add(new HashMap<String, Declaration>());
+	}
+
+	/**
+	 * This method will only ever be called with class/method declarations.
+	 * 
 	 * @param decl
 	 * @return
 	 */
 	public IdentificationTable openScope(Declaration decl) {
-		if(scope.containsKey(decl.name) || getDeclarationAtScope(decl.name) != null) {
+		Declaration current = getDeclarationAtScope(decl.name);
-			Reporter.report(ErrorType.REDEFINITION, decl);
+		if (scope.containsKey(decl.name) || current != null) {
+			Reporter.report(ErrorType.REDEFINITION, decl, current);
 			return null;
 		} else {
 			table.get(table.size() - 1).put(decl.name, decl);
@@ -65,7 +61,9 @@ public class IdentificationTable {
 	}
 
 	/**
-	 * Return nested scope corresponding to declaration (or null if non-existant).
+	 * Return nested scope corresponding to declaration (or null if
+	 * non-existant).
+	 * 
 	 * @param decl
 	 * @return
 	 */
@@ -78,8 +76,9 @@ public class IdentificationTable {
 	}
 
 	/**
-	 * Iterates through all parents and tries to find the specified
+	 * Iterates through all parents and tries to find the specified declaration
-	 * declaration by name.
+	 * by name.
+	 * 
 	 * @param name
 	 * @return
 	 */
@@ -87,28 +86,24 @@ public class IdentificationTable {
 		IdentificationTable current = this;
 		while (current != null) {
 			Declaration decl = current.getDeclarationAtScope(name);
-			if(decl == null) {
+			if (decl == null) current = current.parent;
-				current = current.parent;
+			else return decl;
-			} else {
-				return decl;
-			}
 		}
 
 		return null;
 	}
 
 	/**
-	 * Iterates through levels (from higher to lower) for declaration,
+	 * Iterates through levels (from higher to lower) for declaration, returning
-	 * returning none if it does not exist.
+	 * none if it does not exist.
+	 * 
 	 * @param name
 	 * @return
 	 */
 	public Declaration getDeclarationAtScope(String name) {
 		for (int i = table.size() - 1; i >= 0; i--) {
 			HashMap<String, Declaration> level = table.get(i);
-			if(level.containsKey(name)) {
+			if (level.containsKey(name)) return level.get(name);
-				return level.get(name);
-			}
 		}
 
 		return null;
@@ -116,13 +111,15 @@ public class IdentificationTable {
 
 	/**
 	 * Add declaration to current table's table member.
+	 * 
 	 * @param name
 	 */
 	public void setDeclarationAtScope(Declaration decl) {
 		for (int i = 0; i < table.size(); i++) {
 			HashMap<String, Declaration> level = table.get(i);
 			if (level.containsKey(decl.name)) {
-				Reporter.report(ErrorType.REDEFINITION, decl);
+				Declaration defined = level.get(decl.name);
+				Reporter.report(ErrorType.REDEFINITION, decl, defined);
 				return;
 			}
 		}
@@ -131,15 +128,94 @@ public class IdentificationTable {
 	}
 
 	/**
-	 * Checks that the passed class type does exist.
+	 * Checks whether the specified class has been declared.
-	 * @param ct
+	 * 
+	 * @param t
+	 * @return
 	 */
-	public void validateClassId(Type t) {
+	public boolean classExists(Type t) {
 		if (t.typeKind == TypeKind.CLASS) {
 			ClassType ct = (ClassType) t;
-			if(getDeclaration(ct.className.spelling) == null) {
+			return getDeclaration(ct.className.spelling) != null;
-				Reporter.report(ErrorType.MISSING_DECL, ct);
+		}
+
+		return true;
+	}
+
+	/**
+	 * Determines whether two types match.
+	 * 
+	 * @param t1
+	 * @param t2
+	 * @return
+	 */
+	public static boolean match(Type t1, Type t2) {
+		return IdentificationTable.match(t1, t2, false);
+	}
+
+	/**
+	 * Determines whether two type match, reporting an error if they do not.
+	 * 
+	 * @param t1
+	 * @param t2
+	 * @param report
+	 * @return
+	 */
+	public static boolean match(Type t1, Type t2, boolean report) {
+
+		if (t1.typeKind != t2.typeKind) {
+			if (report) Reporter.report(ErrorType.TYPE_MISMATCH, t1, t2);
+			return false;
+		}
+
+		// Check Class Types match
+		else if (t1.typeKind == TypeKind.CLASS) {
+			ClassType c1 = (ClassType) t1;
+			ClassType c2 = (ClassType) t2;
+			if (!c1.className.spelling.equals(c2.className.spelling)) {
+				if (report) Reporter.report(ErrorType.TYPE_MISMATCH, t1, t2);
+				return false;
 			}
 		}
+
+		// Check array types match
+		else if (t1.typeKind == TypeKind.ARRAY) {
+			ArrayType a1 = (ArrayType) t1;
+			ArrayType a2 = (ArrayType) t2;
+			if (!IdentificationTable.match(a1.eltType, a2.eltType)) {
+				if (report) Reporter.report(ErrorType.TYPE_MISMATCH, t1, t2);
+				return false;
+			}
+		}
+
+		return true;
+	}
+
+	/**
+	 * Determines if the passed method is a valid entry point for the
+	 * compilation phase.
+	 * 
+	 * @param md
+	 * @return
+	 */
+	public static boolean isMainMethod(MethodDecl md) {
+
+		// Check Declaration
+		if (!md.isPrivate && md.isStatic && md.type.typeKind == TypeKind.VOID
+				&& md.name.equals("main") && md.parameterDeclList.size() == 1) {
+
+			// Check Parameter Declaration
+			ParameterDecl pd = md.parameterDeclList.get(0);
+
+			if (pd.type.typeKind != TypeKind.ARRAY) return false;
+			ArrayType at = (ArrayType) pd.type;
+
+			if (at.eltType.typeKind != TypeKind.CLASS) return false;
+			ClassType ct = (ClassType) at.eltType;
+
+			return ct.className.spelling.equals("String");
+		}
+
+		return false;
 	}
 }

miniJava/src/miniJava/ContextualAnalyzer/Reporter.java

@@ -3,17 +3,20 @@ package miniJava.ContextualAnalyzer;
 import miniJava.AbstractSyntaxTrees.*;
 
 enum ErrorType {
-	VAR_COND_ONLY, 		
+	THIS,
-	MISSING_DECL,
+	NONFUNCTION_CALL,
-	UNIDENTIFIED,
+	UNDEFINED,
-	REDEFINITION,
+	STATIC, 
-	INVALID_PARAM_COUNT,
+	VISIBILITY, 
-	INVALID_INDEX,
+	NO_RETURN, 
 	TYPE_MISMATCH, 
-	UNIDENTIFIED_TYPE,
+	REDEFINITION, 
-	TYPE_CLASS_MISMATCH,
+	MAIN_UNDECLARED, 
-	TYPE_ARRAY_MISMATCH,
+	INVALID_PARAM_COUNT, 
-	NO_RETURN_EXPRESSION;
+	MULTIPLE_MAIN, 
+	UNDECLARED_TYPE, 
+	SINGLE_VARCOND, 
+	INVALID_INDEX
 }
 
 public class Reporter {
@@ -21,102 +24,147 @@ public class Reporter {
 	public static boolean error = false;
 
 	/**
-	 * Prints out to console correct error message.
+	 * Convenience function for getting type names.
-	 * @param type
+	 * 
-	 * @param ast
+	 * @param t
+	 * @return
 	 */
-	public static void report(ErrorType type, AST ast) {
+	private static String getTypeName(Type t) {
-		error = true;
+		if (t instanceof ClassType) {
+			ClassType ct = (ClassType) t;
+			return ct.className.spelling;
+		} else if (t instanceof ArrayType) {
+			ArrayType at = (ArrayType) t;
+			return getTypeName(at.eltType);
+		}
+
+		return t.typeKind.toString();
+	}
+
+	/**
+	 * Convenience method for formatting error message.
+	 * 
+	 * @param message
+	 */
+	private static void emit(String message) {
+		System.out.println("***" + message);
+	}
+
+	/**
+	 * Convenience function for managing all error types.
+	 * 
+	 * @param type
+	 * @param a1
+	 * @param a2
+	 */
+	public static void report(ErrorType type, AST a1, AST a2) {
+
 		switch (type) {
 		
-			// VarDeclStmt is only statement in conditional branch
+			// Cannot access 'this' in a static method
-			case VAR_COND_ONLY: {
+			case THIS: {
-				System.out.println("***Conditional statment cannot be followed by a variable declaration statement " + ast.posn);
+				MethodDecl md = (MethodDecl) a2;
+				emit("Cannot reference 'this' " + a1.posn + " in static method '" + md.name + "' " + md.posn);
 				break;
 			}
 		
-			// Declaration does not exist for reference
+			// Attempting to call a non function as a function
-			case MISSING_DECL: {
+			case NONFUNCTION_CALL: {
-				System.out.println("***Reference to a non-existant type " + ast.posn);
+				emit("Not a valid function call at " + a1.posn);
 				break;
 			}
 	
-			// Reports when a reference could not be found
+			// Tried accessing a non-static member from a static method
-			case UNIDENTIFIED: {
+			case STATIC: {
-				System.out.println("***Reference refers to a declaration that does not exist " + ast.posn);
+				MemberDecl md = (MemberDecl) a1;
+				Identifier ident = (Identifier) a2;
+				emit("'" + md.name + "' " + md.posn + " is an instance member and cannot be accessed at " + ident.posn);
+				break;
+			}
+	
+			// Tried accessing a private member of a different class
+			case VISIBILITY: {
+				MemberDecl md = (MemberDecl) a1;
+				Identifier ident = (Identifier) a2;
+				emit("'" + md.name + "' " + md.posn + " is a private member and cannot be accessed at " + ident.posn);
+				break;
+			}
+	
+			// Non-void function does not have a return statement
+			case NO_RETURN: {
+				MethodDecl md = (MethodDecl) a1;
+				emit("'" + md.name + "' " + md.posn + " must have a return statement");
+				break;
+			}
+	
+			// The passed types are not the same
+			case TYPE_MISMATCH: {
+				String name1 = getTypeName((Type) a1);
+				String name2 = getTypeName((Type) a2);
+				if(a1 instanceof ArrayType) name1 += " Array";
+				if(a2 instanceof ArrayType) name2 += " Array";
+				emit("Expected type '" + name1 + "' but got '" + name2 + "' " + a2.posn);
 				break;
 			}
 	
 			// Attempting to redeclare a variable
 			case REDEFINITION: {
-				System.out.println("***Variable has already been defined earlier " + ast.posn);
+				emit("Variable at " + a1.posn + " already declared earlier at " + a2.posn);
 				break;
 			}
 			
-			// A non void function does not have a return statement
+			// Identifier could not be found
-			case NO_RETURN_EXPRESSION: {
+			case UNDEFINED: {
-				System.out.println("***Non-void method does not have a return statement " + ast.posn);
+				Identifier ident = (Identifier) a1;
+				emit("Identifier '" + ident.spelling + "' " + ident.posn + " is undeclared.");
 				break;
 			}
 	
-			// The number of parameters passed is either too few or too great
+			// A public static void main(String[] args) method was not declared
+			case MAIN_UNDECLARED: {
+				emit("A main function was not declared");
+				break;
+			}
+	
+			// Parameter counts of an expression/statement do not match declaration
 			case INVALID_PARAM_COUNT: {
-				System.out.println("***The number of passed parameters does not equal expected count " + ast.posn);
+				MethodDecl md = (MethodDecl) a2;
+				emit("Call to '" + md.name + "' " + a2.posn + " has an invalid parameter count at " + a1.posn);
+				break;
 			}
 	
-			// The expected expression MUST return an int (such as the index of an array)
+			// A public static void main(String[] args) was declared more than once
+			case MULTIPLE_MAIN: {
+				emit("Main function at " + a1.posn + " already declared previously at " + a2.posn);
+				break;
+			}
+	
+			// A reference has been made to a non-existant type
+			case UNDECLARED_TYPE: {
+				if(a1 instanceof Type) {
+					String typeName = getTypeName((Type) a1);
+					emit("'" + typeName + "' " + a1.posn + " has not been declared previously");
+				} else {
+					emit("Identifier at " + a1.posn + " could not be identified");
+				}
+				
+				break;
+			}
+	
+			// A Variable Declaration Statement was made as the only statement of a condition
+			case SINGLE_VARCOND: {
+				emit("Conditional statment cannot be followed by a variable declaration statement exclusively " + a1.posn);
+				break;
+			}
+	
+			// An indexed expression must be of an int type
 			case INVALID_INDEX: {
-				System.out.println("***Expected an integer value as the index of an array " + ast.posn);
+				emit("Index expression is not of type int " + a1.posn);
-				break;
-			}
-			
-			// Hmmm.....
-			case UNIDENTIFIED_TYPE: {
-				System.out.println("***Unexpected type " + ast.posn);
-				break;
-			}
-			
-			// Clear Warning
-			default:
 				break;
 			}
 		}
 
-	/**
-	 * Type specific error reporting.
-	 * @param type
-	 * @param t1
-	 * @param t2
-	 */
-	public static void report(ErrorType type, Type t1, Type t2) {
 		error = true;
-		switch(type) {
-		
-			// Non class/array types don't match
-			case TYPE_MISMATCH: {
-				System.out.println("***Expected type " + t1.typeKind + " but got " + t2.typeKind + t2.posn);
-				break;
 	}
 
-			// Two classes don't match
-			case TYPE_CLASS_MISMATCH: {
-				ClassType c1 = (ClassType) t1;
-				ClassType c2 = (ClassType) t2;
-				System.out.println("***Expected type " + c1.className.spelling + " but got " + c2.className.spelling + c2.posn);
-				break;
-			}
-			
-			// Two arrays don't match
-			case TYPE_ARRAY_MISMATCH: {
-				ArrayType a1 = (ArrayType) t1;
-				ArrayType a2 = (ArrayType) t2;
-				System.out.println("***Expected array type " + a1.eltType.typeKind + " but got " + a2.eltType.typeKind + t2.posn);
-				break;
-			}
-			
-			// Clear Warning
-			default:
-				break;
-		}
-	}
 }

miniJava/src/miniJava/Exceptions/ParsingException.java

@@ -11,7 +11,7 @@ public class ParsingException extends Exception {
 	}
 
 	public ParsingException(Token t) {
-    	super("Parsing error with " + t.toString());
+		super("Parsing error with " + t.spelling + " at " + t.posn.toString());
 	}
 
 }

miniJava/src/miniJava/SyntacticAnalyzer/Parser.java

@@ -19,6 +19,7 @@ public class Parser {
 	/**
 	 * Program ::= (ClassDeclaration)* eot
 	 * @return
+	 * @throws ParsingException
 	 * @throws ScanningException
 	 */
 	public Package parse() throws ParsingException, ScanningException {
@@ -32,14 +33,13 @@ public class Parser {
 	}
 
 	/**
-	 * ClassDeclaration ::=   
+	 * ClassDeclaration ::= class id { (Declarators id (; | MethodDeclaration))* }
-	 *     class id  {       
-	 *	       (Declarators id (; | MethodDeclaration))*   
-	 *     }
 	 * @return
+	 * @throws ParsingException
 	 * @throws ScanningException
 	 */
-	private ClassDecl parseClassDeclaration() throws ParsingException, ScanningException {
+	private ClassDecl parseClassDeclaration() throws ParsingException,
+			ScanningException {
 
 		// Class Header
 		Token classToken = accept(Token.TYPE.CLASS);
@@ -54,7 +54,8 @@ public class Parser {
 		while (peek(1).type != Token.TYPE.RBRACKET) {
 			Declarators d = parseDeclarators();
 			String name = accept(Token.TYPE.ID).spelling;
-			FieldDecl f = new FieldDecl(d.isPrivate, d.isStatic, d.mt, name, d.posn);
+			FieldDecl f = new FieldDecl(d.isPrivate, d.isStatic, d.mt, name,
+					d.posn);
 
 			// Field Declarations
 			if (peek(1).type == Token.TYPE.SEMICOLON) {
@@ -63,7 +64,8 @@ public class Parser {
 			}
 
 			// Method Declarations
-			else mdl.add(parseMethodDeclaration(f));
+			else
+				mdl.add(parseMethodDeclaration(f));
 		}
 
 		accept(Token.TYPE.RBRACKET);
@@ -73,9 +75,11 @@ public class Parser {
 	/**
 	 * Declarators ::= (public | private)? static? Type
 	 * @return
+	 * @throws ParsingException
 	 * @throws ScanningException
 	 */
-	private Declarators parseDeclarators() throws ParsingException, ScanningException {
+	private Declarators parseDeclarators() throws ParsingException,
+			ScanningException {
 
 		// Visibility
 		SourcePosition start = null;
@@ -108,22 +112,22 @@ public class Parser {
 	}
 
 	/**
-	 * * MethodDeclaration ::=
+	 * MethodDeclaration ::= (ParameterList?) { Statement* (return Expression;)? }
-	 *     (ParameterList?) {
+	 * @param f
-	 *	       Statement* (return Expression ;)?
-	 *	   }
-	 * @param f describes the declaratory aspect of the method
 	 * @return
+	 * @throws ParsingException
 	 * @throws ScanningException
 	 */
-	private MethodDecl parseMethodDeclaration(FieldDecl f) throws ParsingException, ScanningException {
+	private MethodDecl parseMethodDeclaration(FieldDecl f)
+			throws ParsingException, ScanningException {
 
 		// Method Header
 		accept(Token.TYPE.LPAREN);
 
 		// Parameter List
 		ParameterDeclList pdl = new ParameterDeclList();
-		if(peek(1).type != Token.TYPE.RPAREN) pdl = parseParameterList();
+		if (peek(1).type != Token.TYPE.RPAREN)
+			pdl = parseParameterList();
 
 		accept(Token.TYPE.RPAREN);
 		accept(Token.TYPE.LBRACKET);
@@ -150,6 +154,7 @@ public class Parser {
 	/**
 	 * Type ::= boolean | void | int ([])? | id ([])?
 	 * @return
+	 * @throws ParsingException
 	 * @throws ScanningException
 	 */
 	private Type parseType() throws ParsingException, ScanningException {
@@ -201,6 +206,7 @@ public class Parser {
 	/**
 	 * ParameterList ::= Type id (, Type id)*
 	 * @return
+	 * @throws ParsingException
 	 * @throws ScanningException
 	 */
 	private ParameterDeclList parseParameterList() throws ParsingException, ScanningException {
@@ -226,6 +232,7 @@ public class Parser {
 	/**
 	 * ArgumentList ::= Expression (, Expression)*
 	 * @return
+	 * @throws ParsingException
 	 * @throws ScanningException
 	 */
 	private ExprList parseArgumentList() throws ParsingException, ScanningException {
@@ -242,6 +249,7 @@ public class Parser {
 	/**
 	 * Reference ::= BaseRef (. BaseRef)*
 	 * @return
+	 * @throws ParsingException
 	 * @throws ScanningException
 	 */
 	private Reference parseReference() throws ParsingException, ScanningException {
@@ -266,6 +274,7 @@ public class Parser {
 	/**
 	 * BaseRef ::= this | id ([ Expression])?
 	 * @return
+	 * @throws ParsingException
 	 * @throws ScanningException
 	 */
 	private Reference parseBaseRef() throws ParsingException, ScanningException {
@@ -295,14 +304,11 @@ public class Parser {
 	}
 
 	/**
-	 * Statement ::=
+	 * Statement ::= {Statement*} | Type id = Expression; | Reference =
-	 *     {Statement*}
+	 * Expression; | Reference ( ArgumentList? ); | if (Expression) Statement
-	 *	 | Type id = Expression;
+	 * (else Statement)? | while (Expression) Statement
-	 *	 | Reference = Expression;
-	 *	 | Reference ( ArgumentList? );
-	 *	 | if (Expression) Statement (else Statement)?
-	 *	 | while (Expression) Statement
 	 * @return
+	 * @throws ParsingException
 	 * @throws ScanningException
 	 */
 	private Statement parseStatement() throws ParsingException, ScanningException {
@@ -349,10 +355,14 @@ public class Parser {
 			}
 	
 			// Type id = Expression ;
-			case BOOLEAN: case VOID: case INT: case ID: {
+			case BOOLEAN:
+			case VOID:
+			case INT:
+			case ID: {
 	
 				// Must be a type though there is a possibility of a reference
-				if(peek(1).type != Token.TYPE.ID || peek(2).type == Token.TYPE.ID
+				if (peek(1).type != Token.TYPE.ID
+						|| peek(2).type == Token.TYPE.ID
 						|| (peek(2).type == Token.TYPE.LSQUARE && peek(3).type == Token.TYPE.RSQUARE)) {
 					Type t = parseType();
 					String name = accept(Token.TYPE.ID).spelling;
@@ -397,13 +407,10 @@ public class Parser {
 	}
 
 	/**
-	 * Expression ::=
+	 * Expression ::= Reference | Reference ( ArgumentList? ) | unop Expression
-	 *     Reference
+	 * | ( Expression ) | num | true | false | new (id() | int [ Expression ] |
-	 *   | Reference ( ArgumentList? )
+	 * id [ Expression ] )
-	 *	 | unop Expression
+	 * 
-	 *   | ( Expression )
-	 *   | num | true | false
-	 *   | new (id() | int [ Expression ] | id [ Expression ] )
 	 * @return
 	 * @throws ScanningException
 	 */
@@ -444,8 +451,8 @@ public class Parser {
 					Token opToken = accept(peek(1).type);
 					Operator o = new Operator(opToken, opToken.posn);
 					e = new UnaryExpr(o, parseSingleExpression(), opToken.posn);
-				} 
+				} else
-				else throw new ParsingException();
+					throw new ParsingException();
 				break;
 			}
 	
@@ -484,7 +491,8 @@ public class Parser {
 			}
 	
 			// Reference ((ArgumentList?))?
-			case THIS: case ID: {
+			case THIS:
+			case ID: {
 				Reference r = parseReference();
 				if (peek(1).type == Token.TYPE.LPAREN) {
 					accept(Token.TYPE.LPAREN);
@@ -502,16 +510,16 @@ public class Parser {
 			}
 	
 			default:
-				throw new ParsingException();
+				throw new ParsingException(peek(1));
 		}
 
 		return e;
 	}
 	
 	/**
-	 * Disjunction & Initial Call:
+	 * Disjunction & Initial Call: Expression ::= Expression binop Expression
-	 * Expression ::= Expression binop Expression
 	 * @return
+	 * @throws ParsingException
 	 * @throws ScanningException
 	 */
 	private Expression parseExpression() throws ParsingException, ScanningException {
@@ -529,6 +537,7 @@ public class Parser {
 	/**
 	 * Conjunction
 	 * @return
+	 * @throws ParsingException
 	 * @throws ScanningException
 	 */
 	private Expression parseCExpression() throws ParsingException, ScanningException {
@@ -546,6 +555,7 @@ public class Parser {
 	/**
 	 * Equality
 	 * @return
+	 * @throws ParsingException
 	 * @throws ScanningException
 	 */
 	private Expression parseEExpression() throws ParsingException, ScanningException {
@@ -563,13 +573,15 @@ public class Parser {
 	/**
 	 * Relational
 	 * @return
+	 * @throws ParsingException
 	 * @throws ScanningException
 	 */
 	private Expression parseRExpression() throws ParsingException, ScanningException {
 
 		Expression e = parseAExpression();
 		while (peek(1).spelling.equals("<") || peek(1).spelling.equals("<=")
-		   || peek(1).spelling.equals(">") || peek(1).spelling.equals(">=")) {
+				|| peek(1).spelling.equals(">")
+				|| peek(1).spelling.equals(">=")) {
 			Token opToken = accept(Token.TYPE.BINOP);
 			Operator o = new Operator(opToken, opToken.posn);
 			e = new BinaryExpr(o, e, parseAExpression(), e.posn);
@@ -581,6 +593,7 @@ public class Parser {
 	/**
 	 * Additive
 	 * @return
+	 * @throws ParsingException
 	 * @throws ScanningException
 	 */
 	private Expression parseAExpression() throws ParsingException, ScanningException {
@@ -598,6 +611,7 @@ public class Parser {
 	/**
 	 * Multiplicative
 	 * @return
+	 * @throws ParsingException
 	 * @throws ScanningException
 	 */
 	private Expression parseMExpression() throws ParsingException, ScanningException {
@@ -614,6 +628,7 @@ public class Parser {
 
 	/**
 	 * Sees what the next token is, caching the result.
+	 * @param lookahead
 	 * @return
 	 * @throws ScanningException
 	 */
@@ -628,9 +643,11 @@ public class Parser {
 		return stream.get(lookahead - 1);
 	}
 
-	
 	/**
 	 * Consumes token or throws exception.
+	 * @param type
+	 * @return
+	 * @throws ParsingException
 	 * @throws ScanningException
 	 */
 	private Token accept(Token.TYPE type) throws ParsingException, ScanningException {

miniJava/src/miniJava/SyntacticAnalyzer/Scanner.java

@@ -20,6 +20,7 @@ public class Scanner {
 
 	/**
 	 * Scans in input, returning next token.
+	 * 
 	 * @return
 	 * @throws IOException
 	 */
@@ -32,7 +33,8 @@ public class Scanner {
 
 			// Check for EOF
 			int c = read();
-        	if(c == -1) return new Token("", Token.TYPE.EOT);
+			if (c == -1)
+				return new Token("", Token.TYPE.EOT);
 
 			// Setup
 			attr += (char) c;
@@ -45,32 +47,42 @@ public class Scanner {
 				break;
 
 			case '+':
-		    		if(peek('+')) throw new ScanningException(col, line);
+				if (peek('+'))
+					throw new ScanningException(col, line);
 				token = new Token(attr, Token.TYPE.BINOP);
 				break;
 
 			case '-':
-		    		if(peek('-')) throw new ScanningException(col, line);
+				if (peek('-'))
+					throw new ScanningException(col, line);
 				token = new Token(attr, Token.TYPE.BINOP);
 				break;
 
 			// Check for comment
 			case '/':
-		    		if(peek('*')) { read(); readComment(); attr = ""; }
+				if (peek('*')) {
-		    		else if(peek('/')) { readLine(); attr = ""; }
+					read();
-		    		else token = new Token(attr, Token.TYPE.BINOP);
+					readComment();
+					attr = "";
+				} else if (peek('/')) {
+					readLine();
+					attr = "";
+				} else
+					token = new Token(attr, Token.TYPE.BINOP);
 				break;
 
 			// Check for c or c=
 			case '>':
 			case '<':
-		    		if(peek('=')) attr += (char) read();
+				if (peek('='))
+					attr += (char) read();
 				token = new Token(attr, Token.TYPE.BINOP);
 				break;
 
 			// Check for ! or !=
 			case '!':
-		    		if(!peek('=')) token = new Token(attr, Token.TYPE.UNOP);
+				if (!peek('='))
+					token = new Token(attr, Token.TYPE.UNOP);
 				else {
 					attr += (char) read();
 					token = new Token(attr, Token.TYPE.BINOP);
@@ -80,7 +92,8 @@ public class Scanner {
 			// Check for && or ||
 			case '&':
 			case '|':
-	    			if(!peek((char) c)) throw new ScanningException(col, line);
+				if (!peek((char) c))
+					throw new ScanningException(col, line);
 				else {
 					attr += (char) read();
 					token = new Token(attr, Token.TYPE.BINOP);
@@ -89,7 +102,8 @@ public class Scanner {
 
 			// Other Operators
 			case '=':
-	    			if(!peek('=')) token = new Token(attr, Token.TYPE.EQUALS);
+				if (!peek('='))
+					token = new Token(attr, Token.TYPE.EQUALS);
 				else {
 					attr += (char) read();
 					token = new Token(attr, Token.TYPE.BINOP);
@@ -164,7 +178,9 @@ public class Scanner {
 				}
 
 				// Unrecognized Character
-	    			else throw new ScanningException(col, line);;
+				else
+					throw new ScanningException(col, line);
+				;
 
 				break;
 			}
@@ -174,9 +190,9 @@ public class Scanner {
 		return token;
 	}
 
-    
 	/**
 	 * Looks at next character in stream without consuming.
+	 * 
 	 * @return
 	 * @throws IOException
 	 */
@@ -192,9 +208,9 @@ public class Scanner {
 		}
 	}
 
-    
 	/**
 	 * Returns whether passed character is next in stream.
+	 * 
 	 * @param c
 	 * @return
 	 * @throws IOException
@@ -211,19 +227,22 @@ public class Scanner {
 		}
 	}
 
-    
 	/**
 	 * Alternative reading that keeps track of position.
+	 * 
 	 * @return
 	 * @throws IOException
 	 */
 	private int read() throws ScanningException {
 		try {
 			int next = input.read();
-	    	if(next != '\n' && next != '\r') col += 1;
+			if (next != '\n' && next != '\r')
+				col += 1;
 			else {
-	    		col = 1; line += 1;
+				col = 1;
-	    		if(peek('\r') || peek('\n')) next = input.read();
+				line += 1;
+				if (peek('\r') || peek('\n'))
+					next = input.read();
 			}
 
 			return next;
@@ -232,9 +251,9 @@ public class Scanner {
 		}
 	}
 
-    
 	/**
 	 * Consumes input until an end of comment has been reached.
+	 * 
 	 * @throws IOException
 	 */
 	private void readComment() throws ScanningException {
@@ -244,35 +263,36 @@ public class Scanner {
 			prev = current;
 
 			int next = read();
-    		if(next == -1) throw new ScanningException(col, line);
+			if (next == -1)
-    		else current = (char) next;
+				throw new ScanningException(col, line);
+			else
+				current = (char) next;
 		}
 	}
 
-    
 	/**
 	 * Consumes input until the end of line is reached
+	 * 
 	 * @throws IOException
 	 */
 	private void readLine() throws ScanningException {
-    	for(int n = 0; n != '\n' && n != '\r' && n != -1; n = read()) {}
+		for (int n = 0; n != '\n' && n != '\r' && n != -1; n = read()) {
+		}
 	}
-    
 
 	/**
 	 * Tells whether character is alphabetical.
+	 * 
 	 * @param c
 	 * @return
 	 */
 	private boolean isAlpha(char c) {
-    	return (c >= 'a' && c <= 'z')
+		return (c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z') || c == '_';
-    		|| (c >= 'A' && c <= 'Z')
-    		|| c == '_';
 	}
 
-    
 	/**
 	 * Tells whether character is numerical.
+	 * 
 	 * @param c
 	 * @return
 	 */
@@ -280,17 +300,14 @@ public class Scanner {
 		return c >= '0' && c <= '9';
 	}
 
-    
 	/**
 	 * Tells wheter character is whitespace.
+	 * 
 	 * @param c
 	 * @return
 	 */
 	private boolean isWhitespace(char c) {
-    	return c == ' '
+		return c == ' ' || c == '\n' || c == '\r' || c == '\t';
-    		|| c == '\n'
-    		|| c == '\r'
-    		|| c == '\t';
 	}
 
 }

miniJava/src/miniJava/SyntacticAnalyzer/Token.java

@@ -7,49 +7,23 @@ public class Token {
 	public enum TYPE {
 
 		// Possible Terminals
-		ID,
+		ID, NUM, UNOP, BINOP,
-		NUM,
-		UNOP,
-		BINOP,
 
 		// Keywords
-		IF,
+		IF, ELSE, NEW, INT, VOID, THIS, TRUE, FALSE, CLASS, WHILE, RETURN, BOOLEAN,
-		ELSE,
-		NEW,
-		INT,
-		VOID,
-		THIS,
-		TRUE,
-		FALSE,
-		CLASS,
-		WHILE,
-		RETURN,
-		BOOLEAN,
 
 		// Declarators
-		STATIC,
+		STATIC, PUBLIC, PRIVATE,
-		PUBLIC,
-		PRIVATE,
 
 		// Other Terminals
-		EQUALS,
+		EQUALS, PERIOD, COMMA, LPAREN, RPAREN, LSQUARE, RSQUARE, LBRACKET, RBRACKET, SEMICOLON,
-		PERIOD,
-		COMMA,
-		LPAREN,
-		RPAREN,
-		LSQUARE,
-		RSQUARE,
-		LBRACKET,
-		RBRACKET,
-		SEMICOLON,
 
 		// End of Token Stream
 		EOT
 	};
 
 	public final static HashMap<String, TYPE> keywords;
-	 static
+	static {
-     {
 		keywords = new HashMap<String, TYPE>();
 		keywords.put("class", TYPE.CLASS);
 		keywords.put("return", TYPE.RETURN);

miniJava/test.java

@@ -1,5 +0,0 @@
-class Test {
-	public int Test() {
-		
-	}
-}