net.sourceforge.phpeclipse/src/net/sourceforge/phpdt/internal/compiler/ast/CaseStatement.java

   1 /*******************************************************************************
   2  * Copyright (c) 2000, 2003 IBM Corporation and others.
   3  * All rights reserved. This program and the accompanying materials
   4  * are made available under the terms of the Common Public License v1.0
   5  * which accompanies this distribution, and is available at
   6  * http://www.eclipse.org/legal/cpl-v10.html
   7  *
   8  * Contributors:
   9  *     IBM Corporation - initial API and implementation
  10  *******************************************************************************/
  11 package net.sourceforge.phpdt.internal.compiler.ast;
  12
  13 import net.sourceforge.phpdt.internal.compiler.ASTVisitor;
  14 import net.sourceforge.phpdt.internal.compiler.codegen.CaseLabel;
  15 import net.sourceforge.phpdt.internal.compiler.flow.FlowContext;
  16 import net.sourceforge.phpdt.internal.compiler.flow.FlowInfo;
  17 import net.sourceforge.phpdt.internal.compiler.impl.Constant;
  18 import net.sourceforge.phpdt.internal.compiler.lookup.BlockScope;
  19 import net.sourceforge.phpdt.internal.compiler.lookup.TypeBinding;
  20
  21 public class CaseStatement extends Statement {
  22
  23         public Expression constantExpression;
  24
  25         public CaseLabel targetLabel;
  26
  27         public CaseStatement(int sourceStart, Expression constantExpression) {
  28                 this.constantExpression = constantExpression;
  29                 this.sourceEnd = constantExpression.sourceEnd;
  30                 this.sourceStart = sourceStart;
  31         }
  32
  33         public FlowInfo analyseCode(BlockScope currentScope,
  34                         FlowContext flowContext, FlowInfo flowInfo) {
  35
  36                 if (constantExpression.constant == NotAConstant)
  37                         currentScope.problemReporter().caseExpressionMustBeConstant(
  38                                         constantExpression);
  39
  40                 this.constantExpression
  41                                 .analyseCode(currentScope, flowContext, flowInfo);
  42                 return flowInfo;
  43         }
  44
  45         /**
  46          * Case code generation
  47          *
  48          */
  49         // public void generateCode(BlockScope currentScope, CodeStream codeStream)
  50         // {
  51         //
  52         // if ((bits & IsReachableMASK) == 0) {
  53         // return;
  54         // }
  55         // int pc = codeStream.position;
  56         // targetLabel.place();
  57         // codeStream.recordPositionsFrom(pc, this.sourceStart);
  58         // }
  59         public StringBuffer printStatement(int tab, StringBuffer output) {
  60
  61                 printIndent(tab, output);
  62                 if (constantExpression == null) {
  63                         output.append("default : "); //$NON-NLS-1$
  64                 } else {
  65                         output.append("case "); //$NON-NLS-1$
  66                         constantExpression.printExpression(0, output).append(" : "); //$NON-NLS-1$
  67                 }
  68                 return output.append(';');
  69         }
  70
  71         /**
  72          * No-op : should use resolveCase(...) instead.
  73          */
  74         public void resolve(BlockScope scope) {
  75         }
  76
  77         public Constant resolveCase(BlockScope scope, TypeBinding switchType,
  78                         SwitchStatement switchStatement) {
  79
  80                 // add into the collection of cases of the associated switch statement
  81                 switchStatement.cases[switchStatement.caseCount++] = this;
  82                 TypeBinding caseType = constantExpression.resolveType(scope);
  83                 if (caseType == null || switchType == null)
  84                         return null;
  85                 if (constantExpression.isConstantValueOfTypeAssignableToType(caseType,
  86                                 switchType))
  87                         return constantExpression.constant;
  88                 if (caseType.isCompatibleWith(switchType))
  89                         return constantExpression.constant;
  90                 scope.problemReporter().typeMismatchErrorActualTypeExpectedType(
  91                                 constantExpression, caseType, switchType);
  92                 return null;
  93         }
  94
  95         public String toString(int tab) {
  96
  97                 String s = tabString(tab);
  98                 s = s + "case " + constantExpression.toStringExpression() + " : "; //$NON-NLS-1$ //$NON-NLS-2$
  99                 return s;
 100         }
 101
 102         public void traverse(ASTVisitor visitor, BlockScope blockScope) {
 103
 104                 if (visitor.visit(this, blockScope)) {
 105                         constantExpression.traverse(visitor, blockScope);
 106                 }
 107                 visitor.endVisit(this, blockScope);
 108         }
 109 }