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Identification/Type Checking

Most of Identification and Type Checking implemented.
master
Joshua Potter 2014-03-21 00:06:09 -04:00
parent f34ccd138d
commit 83c72019f5
20 changed files with 920 additions and 123 deletions

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@ -15,6 +15,15 @@ public abstract class Declaration extends AST {
this.type = type;
}
@Override
public String toString() {
if(posn != null) {
return this.name + "(Line: " + posn.line + ", Column: " + posn.col + ")";
} else {
return super.toString();
}
}
public String name;
public Type type;
}

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@ -1,14 +1,18 @@
package miniJava.AbstractSyntaxTrees;
import miniJava.SyntacticAnalyzer.SourcePosition;
public class Declarators {
public Declarators(boolean isPrivate, boolean isStatic, Type mt) {
public Declarators(boolean isPrivate, boolean isStatic, Type mt, SourcePosition posn) {
this.isPrivate = isPrivate;
this.isStatic = isStatic;
this.mt = mt;
this.posn = posn;
}
public boolean isPrivate;
public boolean isStatic;
public Type mt;
public SourcePosition posn;
}

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@ -13,6 +13,11 @@ public class FieldDeclList implements Iterable<FieldDecl>
fieldDeclList = new ArrayList<FieldDecl>();
}
public FieldDeclList(FieldDecl f) {
fieldDeclList = new ArrayList<FieldDecl>();
fieldDeclList.add(f);
}
public void add(FieldDecl cd){
fieldDeclList.add(cd);
}

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@ -17,4 +17,5 @@ public class Identifier extends Terminal {
return v.visitIdentifier(this, o);
}
public Declaration decl = null;
}

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@ -13,6 +13,11 @@ public class MethodDeclList implements Iterable<MethodDecl>
methodDeclList = new ArrayList<MethodDecl>();
}
public MethodDeclList(MethodDecl m) {
methodDeclList = new ArrayList<MethodDecl>();
methodDeclList.add(m);
}
public void add(MethodDecl cd){
methodDeclList.add(cd);
}

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@ -13,6 +13,11 @@ public class ParameterDeclList implements Iterable<ParameterDecl>
parameterDeclList = new ArrayList<ParameterDecl>();
}
public ParameterDeclList(ParameterDecl p) {
parameterDeclList = new ArrayList<ParameterDecl>();
parameterDeclList.add(p);
}
public void add(ParameterDecl s){
parameterDeclList.add(s);
}

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@ -13,4 +13,5 @@ public abstract class Reference extends AST
super(posn);
}
public Declaration decl;
}

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@ -12,5 +12,6 @@ public enum TypeKind {
CLASS,
ARRAY,
UNSUPPORTED,
ERROR;
ERROR,
VALID;
}

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@ -3,9 +3,11 @@ package miniJava;
import java.io.*;
import miniJava.SyntacticAnalyzer.*;
import miniJava.SyntacticAnalyzer.Errors.*;
import miniJava.AbstractSyntaxTrees.*;
import miniJava.AbstractSyntaxTrees.ASTDisplay;
import miniJava.AbstractSyntaxTrees.Package;
import miniJava.ContextualAnalyzer.Analyzer;
import miniJava.ContextualAnalyzer.Reporter;
import miniJava.Exceptions.*;
public class Compiler {
@ -26,18 +28,24 @@ public class Compiler {
Package p = parser.parse();
// Display
ASTDisplay display = new ASTDisplay();
display.showTree(p);
// ASTDisplay display = new ASTDisplay();
// display.showTree(p);
// Identification/Type Checking
Analyzer analyzer = new Analyzer();
analyzer.visitPackage(p, null);
if(Reporter.error) System.exit(rc);
System.exit(0);
} catch(FileNotFoundException e) {
System.out.println(e.getMessage());
System.out.println("***" + e.getMessage());
} catch(IOException e) {
System.out.println(e.getMessage());
System.out.println("***" + e.getMessage());
}catch(ScanningException e) {
System.out.println(e.getMessage());
System.out.println("***" + e.getMessage());
} catch(ParsingException e) {
System.out.println(e.getMessage());
System.out.println("***" + e.getMessage());
}
System.exit(rc);

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@ -0,0 +1,455 @@
package miniJava.ContextualAnalyzer;
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 IdentificationTable table = new IdentificationTable();
// Current class decl is for use with the 'this' keyword
private Declaration currentClassDecl = null;
/**
* Adds predefined names to identification table.
*/
public Analyzer() {
try {
String __PrintStream = "class _PrintStream { public void println(int n){} }";
new Parser(new Scanner(__PrintStream)).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.
* @param t1
* @param t2
* @return
*/
private void match(Type t1, Type t2) {
// Check class types match
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);
}
}
@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
* all classes and methods first.
*/
for(ClassDecl cd : prog.classDeclList) {
IdentificationTable cdTable = table.openScope(cd);
if(cdTable != null) {
// Simply add fields to current scope
for(FieldDecl fd : cd.fieldDeclList) {
cdTable.setDeclarationAtScope(fd);
}
// Just Add Declaration (also creates another identification table)
for(MethodDecl md : cd.methodDeclList) {
cdTable.openScope(md);
}
}
}
// Begin Traversal
for(ClassDecl cd : prog.classDeclList) {
currentClassDecl = cd;
cd.visit(this, table);
}
return null;
}
@Override
public Type visitClassDecl(ClassDecl cd, IdentificationTable arg) {
IdentificationTable cdTable = arg.getScope(cd);
if(cdTable != null) {
for(FieldDecl fd : cd.fieldDeclList) {
fd.visit(this, cdTable);
}
for(MethodDecl md : cd.methodDeclList) {
md.visit(this, cdTable);
}
}
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);
return fd.type;
}
@Override
public Type visitMethodDecl(MethodDecl md, IdentificationTable arg) {
IdentificationTable mdTable = arg.getScope(md);
// Must check that the type of the method can be identified
table.validateClassId(md.type);
// Continue Traversal
if(mdTable != null) {
for(ParameterDecl pd : md.parameterDeclList) {
pd.visit(this, mdTable);
}
for(Statement s : md.statementList) {
s.visit(this, mdTable);
}
// Check that return type matches expected type
if(md.returnExp != null) {
Type returnType = md.returnExp.visit(this, mdTable);
match(md.type, returnType);
} 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);
return pd.type;
}
@Override
public Type visitVarDecl(VarDecl decl, IdentificationTable arg) {
arg.setDeclarationAtScope(decl);
table.validateClassId(decl.type);
return decl.type;
}
@Override
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
public Type visitBlockStmt(BlockStmt stmt, IdentificationTable arg) {
arg.pushLevel();
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
Type initExpType = stmt.initExp.visit(this, arg);
Type varDeclType = stmt.varDecl.visit(this, arg);
match(varDeclType, initExpType);
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);
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);
} 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);
}
}
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);
// A single vardecl cannot exist after a conditional statement
if(stmt.thenStmt instanceof VarDeclStmt) {
Reporter.report(ErrorType.VAR_COND_ONLY, stmt.thenStmt);
} else {
stmt.thenStmt.visit(this, arg);
if(stmt.elseStmt != null) {
if(stmt.elseStmt instanceof VarDeclStmt) {
Reporter.report(ErrorType.VAR_COND_ONLY, stmt.elseStmt);
} else {
stmt.elseStmt.visit(this, arg);
}
}
}
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);
if(stmt.body instanceof VarDeclStmt) {
Reporter.report(ErrorType.VAR_COND_ONLY, stmt.body);
} else {
stmt.body.visit(this, arg);
}
return null;
}
@Override
public Type visitUnaryExpr(UnaryExpr expr, IdentificationTable arg) {
Type opType = expr.operator.visit(this, arg);
Type exprType = expr.expr.visit(this, arg);
match(opType, exprType);
return null;
}
@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);
match(opType, rightType);
return null;
}
@Override
public Type visitRefExpr(RefExpr expr, IdentificationTable arg) {
return expr.ref.visit(this, arg);
}
@Override
public Type visitCallExpr(CallExpr expr, IdentificationTable arg) {
Type functionType = expr.functionRef.visit(this, arg);
// 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);
} 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);
}
}
return functionType;
}
@Override
public Type visitLiteralExpr(LiteralExpr expr, IdentificationTable arg) {
return expr.literal.visit(this, arg);
}
@Override
public Type visitNewObjectExpr(NewObjectExpr expr, IdentificationTable arg) {
return expr.classtype.visit(this, arg);
}
@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);
}
return expr.eltType.visit(this, arg);
}
@Override
public Type visitQualifiedRef(QualifiedRef ref, IdentificationTable arg) {
ref.ref.visit(this, arg);
ref.id.visit(this, arg);
// Check that each declaration is nested properly
if(ref.decl == null || table.getDeclaration(ref.decl.name) == null) {
System.out.println(ref.id.spelling);
// report(ErrorType.MISSING_DECL, ref.ref.decl);
}
return null;
}
@Override
public Type visitIndexedRef(IndexedRef ref, IdentificationTable arg) {
ref.ref.visit(this, arg);
ref.decl = ref.ref.decl;
// 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);
}
return ref.decl.type;
}
@Override
public Type visitIdRef(IdRef ref, IdentificationTable arg) {
ref.id.visit(this, arg);
ref.decl = ref.id.decl;
return ref.decl.type;
}
@Override
public Type visitThisRef(ThisRef ref, IdentificationTable arg) {
ref.decl = currentClassDecl;
return ref.decl.type;
}
@Override
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);
if(decl == null) {
Reporter.report(ErrorType.UNIDENTIFIED, id);
return new BaseType(TypeKind.ERROR, null);
} else {
id.decl = decl;
return decl.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.INT, op.posn);
default:
Reporter.report(ErrorType.UNIDENTIFIED_TYPE, op);
return new BaseType(TypeKind.ERROR, op.posn);
}
}
@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);
}
}

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@ -0,0 +1,145 @@
package miniJava.ContextualAnalyzer;
import java.util.HashMap;
import java.util.ArrayList;
import miniJava.AbstractSyntaxTrees.ClassType;
import miniJava.AbstractSyntaxTrees.Declaration;
import miniJava.AbstractSyntaxTrees.Type;
import miniJava.AbstractSyntaxTrees.TypeKind;
public class IdentificationTable {
private IdentificationTable parent;
private HashMap<String, IdentificationTable> scope;
private ArrayList<HashMap<String, Declaration>> table;
/**
*
*/
public IdentificationTable() {
this(null);
}
/**
*
* @param parent
*/
public IdentificationTable(IdentificationTable parent) {
this.parent = parent;
this.scope = new HashMap<String, IdentificationTable>();
this.table = new ArrayList<HashMap<String, Declaration>>();
this.table.add(new HashMap<String, Declaration>());
}
/**
* Adds another level for variables to be stored at (they will be
* 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
* @param decl
* @return
*/
public IdentificationTable openScope(Declaration decl) {
if(scope.containsKey(decl.name) || getDeclarationAtScope(decl.name) != null) {
Reporter.report(ErrorType.REDEFINITION, decl);
return null;
} else {
table.get(table.size() - 1).put(decl.name, decl);
scope.put(decl.name, new IdentificationTable(this));
return scope.get(decl.name);
}
}
/**
* Return nested scope corresponding to declaration (or null if non-existant).
* @param decl
* @return
*/
public IdentificationTable getScope(Declaration decl) {
if(scope.containsKey(decl.name)) {
return scope.get(decl.name);
}
return null;
}
/**
* Iterates through all parents and tries to find the specified
* declaration by name.
* @param name
* @return
*/
public Declaration getDeclaration(String name) {
IdentificationTable current = this;
while(current != null) {
Declaration decl = current.getDeclarationAtScope(name);
if(decl == null) {
current = current.parent;
} else {
return decl;
}
}
return null;
}
/**
* Iterates through levels (from higher to lower) for declaration,
* returning 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)) {
return level.get(name);
}
}
return null;
}
/**
* 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);
return;
}
}
table.get(table.size() - 1).put(decl.name, decl);
}
/**
* Checks that the passed class type does exist.
* @param ct
*/
public void validateClassId(Type t) {
if(t.typeKind == TypeKind.CLASS) {
ClassType ct = (ClassType) t;
if(getDeclaration(ct.className.spelling) == null) {
Reporter.report(ErrorType.MISSING_DECL, ct);
}
}
}
}

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@ -0,0 +1,122 @@
package miniJava.ContextualAnalyzer;
import miniJava.AbstractSyntaxTrees.*;
enum ErrorType {
VAR_COND_ONLY,
MISSING_DECL,
UNIDENTIFIED,
REDEFINITION,
INVALID_PARAM_COUNT,
INVALID_INDEX,
TYPE_MISMATCH,
UNIDENTIFIED_TYPE,
TYPE_CLASS_MISMATCH,
TYPE_ARRAY_MISMATCH,
NO_RETURN_EXPRESSION;
}
public class Reporter {
public static boolean error = false;
/**
* Prints out to console correct error message.
* @param type
* @param ast
*/
public static void report(ErrorType type, AST ast) {
error = true;
switch(type) {
// VarDeclStmt is only statement in conditional branch
case VAR_COND_ONLY: {
System.out.println("***Conditional statment cannot be followed by a variable declaration statement " + ast.posn);
break;
}
// Declaration does not exist for reference
case MISSING_DECL: {
System.out.println("***Reference to a non-existant type " + ast.posn);
break;
}
// Reports when a reference could not be found
case UNIDENTIFIED: {
System.out.println("***Reference refers to a declaration that does not exist " + ast.posn);
break;
}
// Attempting to redeclare a variable
case REDEFINITION: {
System.out.println("***Variable has already been defined earlier " + ast.posn);
break;
}
// A non void function does not have a return statement
case NO_RETURN_EXPRESSION: {
System.out.println("***Non-void method does not have a return statement " + ast.posn);
break;
}
// The number of parameters passed is either too few or too great
case INVALID_PARAM_COUNT: {
System.out.println("***The number of passed parameters does not equal expected count " + ast.posn);
}
// The expected expression MUST return an int (such as the index of an array)
case INVALID_INDEX: {
System.out.println("***Expected an integer value as the index of an array " + ast.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;
}
}
}

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@ -0,0 +1,10 @@
package miniJava.Exceptions;
public class IdentificationException extends Exception {
private static final long serialVersionUID = 1L;
public IdentificationException() {
super("Identification Error!");
}
}

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@ -1,4 +1,4 @@
package miniJava.SyntacticAnalyzer.Errors;
package miniJava.Exceptions;
import miniJava.SyntacticAnalyzer.Token;

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@ -1,4 +1,4 @@
package miniJava.SyntacticAnalyzer.Errors;
package miniJava.Exceptions;
public class ScanningException extends Exception {

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@ -4,7 +4,7 @@ import java.util.LinkedList;
import miniJava.AbstractSyntaxTrees.*;
import miniJava.AbstractSyntaxTrees.Package;
import miniJava.SyntacticAnalyzer.Errors.*;
import miniJava.Exceptions.*;
public class Parser {
@ -28,7 +28,7 @@ public class Parser {
}
accept(Token.TYPE.EOT);
return new Package(decls, null);
return new Package(decls, new SourcePosition(0, 0));
}
/**
@ -42,7 +42,7 @@ public class Parser {
private ClassDecl parseClassDeclaration() throws ParsingException, ScanningException {
// Class Header
accept(Token.TYPE.CLASS);
Token classToken = accept(Token.TYPE.CLASS);
String cn = accept(Token.TYPE.ID).spelling;
accept(Token.TYPE.LBRACKET);
@ -54,7 +54,7 @@ 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, null);
FieldDecl f = new FieldDecl(d.isPrivate, d.isStatic, d.mt, name, d.posn);
// Field Declarations
if(peek(1).type == Token.TYPE.SEMICOLON) {
@ -67,7 +67,7 @@ public class Parser {
}
accept(Token.TYPE.RBRACKET);
return new ClassDecl(cn, fdl, mdl, null);
return new ClassDecl(cn, fdl, mdl, classToken.posn);
}
/**
@ -78,23 +78,33 @@ public class Parser {
private Declarators parseDeclarators() throws ParsingException, ScanningException {
// Visibility
SourcePosition start = null;
boolean isPrivate = false;
if(peek(1).type == Token.TYPE.PUBLIC) {
accept(Token.TYPE.PUBLIC);
start = accept(Token.TYPE.PUBLIC).posn;
} else if(peek(1).type == Token.TYPE.PRIVATE) {
isPrivate = true;
accept(Token.TYPE.PRIVATE);
start = accept(Token.TYPE.PRIVATE).posn;
}
// Class Methods
boolean isStatic = false;
if(peek(1).type == Token.TYPE.STATIC) {
isStatic = true;
if(start == null) {
start = accept(Token.TYPE.STATIC).posn;
} else {
accept(Token.TYPE.STATIC);
}
}
Type t = parseType();
return new Declarators(isPrivate, isStatic, t);
if(start == null) {
start = t.posn;
}
return new Declarators(isPrivate, isStatic, t, start);
}
/**
@ -134,7 +144,7 @@ public class Parser {
}
accept(Token.TYPE.RBRACKET);
return new MethodDecl(f, pdl, stl, re, null);
return new MethodDecl(f, pdl, stl, re, f.posn);
}
/**
@ -144,38 +154,40 @@ public class Parser {
*/
private Type parseType() throws ParsingException, ScanningException {
SourcePosition posn = null;
switch(peek(1).type) {
case BOOLEAN:
accept(Token.TYPE.BOOLEAN);
return new BaseType(TypeKind.BOOLEAN, null);
posn = accept(Token.TYPE.BOOLEAN).posn;
return new BaseType(TypeKind.BOOLEAN, posn);
case VOID:
accept(Token.TYPE.VOID);
return new BaseType(TypeKind.VOID, null);
posn = accept(Token.TYPE.VOID).posn;
return new BaseType(TypeKind.VOID, posn);
case INT: {
accept(Token.TYPE.INT);
BaseType b = new BaseType(TypeKind.INT, null);
posn = accept(Token.TYPE.INT).posn;
BaseType b = new BaseType(TypeKind.INT, posn);
if(peek(1).type == Token.TYPE.LSQUARE) {
accept(Token.TYPE.LSQUARE);
accept(Token.TYPE.RSQUARE);
return new ArrayType(b, null);
return new ArrayType(b, posn);
}
return b;
}
case ID: {
String cn = accept(peek(1).type).spelling;
Identifier i = new Identifier(cn, null);
ClassType c = new ClassType(i, null);
Token id = accept(peek(1).type);
Identifier i = new Identifier(id.spelling, id.posn);
ClassType c = new ClassType(i, id.posn);
if(peek(1).type == Token.TYPE.LSQUARE) {
accept(Token.TYPE.LSQUARE);
accept(Token.TYPE.RSQUARE);
return new ArrayType(c, null);
return new ArrayType(c, id.posn);
}
return c;
@ -197,15 +209,15 @@ public class Parser {
// First Parameter
Type t = parseType();
String name = accept(Token.TYPE.ID).spelling;
decls.add(new ParameterDecl(t, name, null));
Token id = accept(Token.TYPE.ID);
decls.add(new ParameterDecl(t, id.spelling, id.posn));
// Remainder of List
while(peek(1).type == Token.TYPE.COMMA) {
accept(Token.TYPE.COMMA);
t = parseType();
name = accept(Token.TYPE.ID).spelling;
decls.add(new ParameterDecl(t, name, null));
Type nextType = parseType();
Token nextId = accept(Token.TYPE.ID);
decls.add(new ParameterDecl(nextType, nextId.spelling, nextId.posn));
}
return decls;
@ -236,15 +248,15 @@ public class Parser {
Reference r = parseBaseRef();
while(peek(1).type == Token.TYPE.PERIOD) {
accept(Token.TYPE.PERIOD);
String name = accept(Token.TYPE.ID).spelling;
Identifier id = new Identifier(name, null);
r = new QualifiedRef(r, id, null);
Token tokenId = accept(Token.TYPE.ID);
Identifier id = new Identifier(tokenId.spelling, tokenId.posn);
r = new QualifiedRef(r, id, tokenId.posn);
if(peek(1).type == Token.TYPE.LSQUARE) {
accept(Token.TYPE.LSQUARE);
Expression e = parseExpression();
accept(Token.TYPE.RSQUARE);
r = new IndexedRef(r, e, null);
r = new IndexedRef(r, e, tokenId.posn);
}
}
@ -259,21 +271,22 @@ public class Parser {
private Reference parseBaseRef() throws ParsingException, ScanningException {
switch(peek(1).type) {
case THIS:
accept(Token.TYPE.THIS);
return new ThisRef(null);
case THIS: {
Token thisToken = accept(Token.TYPE.THIS);
return new ThisRef(thisToken.posn);
}
// id ([ Expression])?
default: {
String id = accept(Token.TYPE.ID).spelling;
Identifier i = new Identifier(id, null);
IdRef r = new IdRef(i, null);
Token id = accept(Token.TYPE.ID);
Identifier i = new Identifier(id.spelling, id.posn);
IdRef r = new IdRef(i, id.posn);
if(peek(1).type == Token.TYPE.LSQUARE) {
accept(Token.TYPE.LSQUARE);
Expression e = parseExpression();
accept(Token.TYPE.RSQUARE);
return new IndexedRef(r, e, null);
return new IndexedRef(r, e, id.posn);
}
return r;
@ -298,19 +311,19 @@ public class Parser {
// { Statement* }
case LBRACKET: {
accept(Token.TYPE.LBRACKET);
Token leftToken = accept(Token.TYPE.LBRACKET);
StatementList stl = new StatementList();
while(peek(1).type != Token.TYPE.RBRACKET) {
stl.add(parseStatement());
}
accept(Token.TYPE.RBRACKET);
return new BlockStmt(stl, null);
return new BlockStmt(stl, leftToken.posn);
}
// if (Expression) Statement (else Statement)?
case IF: {
accept(Token.TYPE.IF);
Token ifToken = accept(Token.TYPE.IF);
accept(Token.TYPE.LPAREN);
Expression e = parseExpression();
accept(Token.TYPE.RPAREN);
@ -318,21 +331,21 @@ public class Parser {
if(peek(1).type == Token.TYPE.ELSE) {
accept(Token.TYPE.ELSE);
Statement s2 = parseStatement();
return new IfStmt(e, s1, s2, null);
return new IfStmt(e, s1, s2, ifToken.posn);
}
return new IfStmt(e, s1, null);
return new IfStmt(e, s1, ifToken.posn);
}
// while (Expression) Statement
case WHILE: {
accept(Token.TYPE.WHILE);
Token whileToken = accept(Token.TYPE.WHILE);
accept(Token.TYPE.LPAREN);
Expression e = parseExpression();
accept(Token.TYPE.RPAREN);
Statement s = parseStatement();
return new WhileStmt(e, s, null);
return new WhileStmt(e, s, whileToken.posn);
}
// Type id = Expression ;
@ -343,13 +356,13 @@ public class Parser {
||(peek(2).type == Token.TYPE.LSQUARE && peek(3).type == Token.TYPE.RSQUARE)) {
Type t = parseType();
String name = accept(Token.TYPE.ID).spelling;
VarDecl v = new VarDecl(t, name, null);
VarDecl v = new VarDecl(t, name, t.posn);
accept(Token.TYPE.EQUALS);
Expression e = parseExpression();
accept(Token.TYPE.SEMICOLON);
return new VarDeclStmt(v, e, null);
return new VarDeclStmt(v, e, t.posn);
}
/* Fall Through */
@ -367,14 +380,14 @@ public class Parser {
e = parseArgumentList();
}
accept(Token.TYPE.RPAREN);
s = new CallStmt(r, e, null);
s = new CallStmt(r, e, r.posn);
}
// Reference = Expression ;
else {
accept(Token.TYPE.EQUALS);
Expression e = parseExpression();
s = new AssignStmt(r, e, null);
s = new AssignStmt(r, e, r.posn);
}
accept(Token.TYPE.SEMICOLON);
@ -401,18 +414,18 @@ public class Parser {
// num
case NUM: {
String number = accept(Token.TYPE.NUM).spelling;
IntLiteral i = new IntLiteral(number, null);
e = new LiteralExpr(i, null);
Token number = accept(Token.TYPE.NUM);
IntLiteral i = new IntLiteral(number.spelling, number.posn);
e = new LiteralExpr(i, number.posn);
break;
}
// true | false
case TRUE:
case FALSE: {
String bool = accept(peek(1).type).spelling;
BooleanLiteral b = new BooleanLiteral(bool, null);
e = new LiteralExpr(b, null);
Token bool = accept(peek(1).type);
BooleanLiteral b = new BooleanLiteral(bool.spelling, bool.posn);
e = new LiteralExpr(b, bool.posn);
break;
}
@ -428,8 +441,9 @@ public class Parser {
case UNOP:
case BINOP: {
if(peek(1).spelling.equals("!") || peek(1).spelling.equals("-")) {
Operator o = new Operator(accept(peek(1).type), null);
e = new UnaryExpr(o, parseSingleExpression(), null);
Token opToken = accept(peek(1).type);
Operator o = new Operator(opToken, opToken.posn);
e = new UnaryExpr(o, parseSingleExpression(), opToken.posn);
}
else throw new ParsingException();
break;
@ -437,7 +451,7 @@ public class Parser {
// new ( int [ Expression ] | id ( ) | id [ Expression ] )
case NEW: {
accept(Token.TYPE.NEW);
Token newToken = accept(Token.TYPE.NEW);
if(peek(1).type == Token.TYPE.INT) {
accept(Token.TYPE.INT);
@ -445,24 +459,24 @@ public class Parser {
Expression e2 = parseExpression();
accept(Token.TYPE.RSQUARE);
BaseType b = new BaseType(TypeKind.INT, null);
e = new NewArrayExpr(b, e2, null);
BaseType b = new BaseType(TypeKind.INT, newToken.posn);
e = new NewArrayExpr(b, e2, newToken.posn);
}
else {
String cn = accept(Token.TYPE.ID).spelling;
Identifier i = new Identifier(cn, null);
ClassType c = new ClassType(i, null);
Token id = accept(Token.TYPE.ID);
Identifier i = new Identifier(id.spelling, id.posn);
ClassType c = new ClassType(i, id.posn);
if(peek(1).type == Token.TYPE.LPAREN){
accept(Token.TYPE.LPAREN);
accept(Token.TYPE.RPAREN);
e = new NewObjectExpr(c, null);
e = new NewObjectExpr(c, id.posn);
} else {
accept(Token.TYPE.LSQUARE);
Expression e2 = parseExpression();
accept(Token.TYPE.RSQUARE);
e = new NewArrayExpr(c, e2, null);
e = new NewArrayExpr(c, e2, id.posn);
}
}
@ -479,9 +493,9 @@ public class Parser {
el = parseArgumentList();
}
accept(Token.TYPE.RPAREN);
e = new CallExpr(r, el, null);
e = new CallExpr(r, el, r.posn);
} else {
e = new RefExpr(r, null);
e = new RefExpr(r, r.posn);
}
break;
@ -504,8 +518,9 @@ public class Parser {
Expression e = parseCExpression();
while(peek(1).spelling.equals("||")) {
Operator o = new Operator(accept(Token.TYPE.BINOP), null);
e = new BinaryExpr(o, e, parseCExpression(), null);
Token opToken = accept(Token.TYPE.BINOP);
Operator o = new Operator(opToken, opToken.posn);
e = new BinaryExpr(o, e, parseCExpression(), e.posn);
}
return e;
@ -520,8 +535,9 @@ public class Parser {
Expression e = parseEExpression();
while(peek(1).spelling.equals("&&")) {
Operator o = new Operator(accept(Token.TYPE.BINOP), null);
e = new BinaryExpr(o, e, parseEExpression(), null);
Token opToken = accept(Token.TYPE.BINOP);
Operator o = new Operator(opToken, opToken.posn);
e = new BinaryExpr(o, e, parseEExpression(), e.posn);
}
return e;
@ -536,8 +552,9 @@ public class Parser {
Expression e = parseRExpression();
while(peek(1).spelling.equals("==") || peek(1).spelling.equals("!=")) {
Operator o = new Operator(accept(Token.TYPE.BINOP), null);
e = new BinaryExpr(o, e, parseRExpression(), null);
Token opToken = accept(Token.TYPE.BINOP);
Operator o = new Operator(opToken, opToken.posn);
e = new BinaryExpr(o, e, parseRExpression(), e.posn);
}
return e;
@ -553,8 +570,9 @@ public class Parser {
Expression e = parseAExpression();
while(peek(1).spelling.equals("<") || peek(1).spelling.equals("<=")
|| peek(1).spelling.equals(">") || peek(1).spelling.equals(">=")) {
Operator o = new Operator(accept(Token.TYPE.BINOP), null);
e = new BinaryExpr(o, e, parseAExpression(), null);
Token opToken = accept(Token.TYPE.BINOP);
Operator o = new Operator(opToken, opToken.posn);
e = new BinaryExpr(o, e, parseAExpression(), e.posn);
}
return e;
@ -569,8 +587,9 @@ public class Parser {
Expression e = parseMExpression();
while(peek(1).spelling.equals("+") || peek(1).spelling.equals("-")) {
Operator o = new Operator(accept(Token.TYPE.BINOP), null);
e = new BinaryExpr(o, e, parseMExpression(), null);
Token opToken = accept(Token.TYPE.BINOP);
Operator o = new Operator(opToken, opToken.posn);
e = new BinaryExpr(o, e, parseMExpression(), e.posn);
}
return e;
@ -585,8 +604,9 @@ public class Parser {
Expression e = parseSingleExpression();
while(peek(1).spelling.equals("*") || peek(1).spelling.equals("/")) {
Operator o = new Operator(accept(Token.TYPE.BINOP), null);
e = new BinaryExpr(o, e, parseSingleExpression(), null);
Token opToken = accept(Token.TYPE.BINOP);
Operator o = new Operator(opToken, opToken.posn);
e = new BinaryExpr(o, e, parseSingleExpression(), e.posn);
}
return e;

View File

@ -1,8 +1,7 @@
package miniJava.SyntacticAnalyzer;
import java.io.*;
import miniJava.SyntacticAnalyzer.Errors.ScanningException;
import miniJava.Exceptions.*;
public class Scanner {
@ -14,6 +13,11 @@ public class Scanner {
this.input = input;
}
public Scanner(String input) {
StringReader reader = new StringReader(input);
this.input = new BufferedReader(reader);
}
/**
* Scans in input, returning next token.
* @return
@ -132,7 +136,7 @@ public class Scanner {
// Identifier or Keyword
if(isAlpha((char) c)) {
for(char n = peek(); isAlpha(n) || isDigit(n) || n == '_';) {
for(char n = peek(); isAlpha(n) || isDigit(n);) {
attr += (char) read();
n = peek();
}
@ -166,6 +170,7 @@ public class Scanner {
}
}
token.posn = new SourcePosition(line, col - token.spelling.length());
return token;
}
@ -216,7 +221,10 @@ public class Scanner {
try {
int next = input.read();
if(next != '\n' && next != '\r') col += 1;
else { col = 1; line += 1; }
else {
col = 1; line += 1;
if(peek('\r') || peek('\n')) next = input.read();
}
return next;
} catch(IOException e) {
@ -230,19 +238,15 @@ public class Scanner {
* @throws IOException
*/
private void readComment() throws ScanningException {
try {
char prev = '\0', current = '\0';
while(prev != '*' || current != '/') {
prev = current;
int next = input.read();
if(next == -1) throw new IOException();
int next = read();
if(next == -1) throw new ScanningException(col, line);
else current = (char) next;
}
} catch(IOException e) {
throw new ScanningException(col, line);
}
}
@ -251,11 +255,7 @@ public class Scanner {
* @throws IOException
*/
private void readLine() throws ScanningException {
try {
for(int n = 0; n != '\n' && n != '\r' && n != -1; n = input.read()) {}
} catch(IOException e) {
throw new ScanningException(col, line);
}
for(int n = 0; n != '\n' && n != '\r' && n != -1; n = read()) {}
}
@ -266,7 +266,8 @@ public class Scanner {
*/
private boolean isAlpha(char c) {
return (c >= 'a' && c <= 'z')
|| (c >= 'A' && c <= 'Z');
|| (c >= 'A' && c <= 'Z')
|| c == '_';
}

View File

@ -9,4 +9,9 @@ public class SourcePosition {
this.col = col;
this.line = line;
}
@Override
public String toString() {
return "(Line: " + line + ", Column: " + col + ")";
}
}

View File

@ -69,10 +69,12 @@ public class Token {
}
public final TYPE type;
public SourcePosition posn;
public final String spelling;
public Token(String spelling, TYPE type) {
this.type = type;
this.posn = null;
this.spelling = spelling;
}
}

View File

@ -1,7 +1,5 @@
// PA1 lex binop pass
class id {
void p(){
int x = 1 + 2 * 3 / 4 > 5 >= 6 < 7 <= 8 != 9 && 0 || 1;
}
}
class Test {
public int Test() {
}
}