net.sourceforge.phpeclipse/src/net/sourceforge/phpdt/internal/compiler/ast/DoubleLiteral.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.IAbstractSyntaxTreeVisitor;
  14 import net.sourceforge.phpdt.internal.compiler.impl.Constant;
  15 import net.sourceforge.phpdt.internal.compiler.lookup.BlockScope;
  16 import net.sourceforge.phpdt.internal.compiler.lookup.TypeBinding;
  17
  18 public class DoubleLiteral extends NumberLiteral {
  19         double value;
  20
  21         public DoubleLiteral(char[] token, int s, int e) {
  22                 super(token, s, e);
  23         }
  24
  25         public void computeConstant() {
  26
  27                 // the source is correctly formated so the exception should never occurs
  28
  29                 Double computedValue;
  30                 try {
  31                         computedValue = Double.valueOf(String.valueOf(source));
  32                 } catch (NumberFormatException e) {
  33                         return;
  34                 } // how can it happen ????
  35
  36                 if (computedValue.doubleValue() > Double.MAX_VALUE)
  37                         return; // may be Infinity
  38                 if (computedValue.doubleValue() < Double.MIN_VALUE) { // only a true 0
  39                                                                                                                                 // can be made
  40                                                                                                                                 // of zeros
  41                         // 2.00000000000000000e-324 is illegal ....
  42                         label: for (int i = 0; i < source.length; i++) { // it is welled
  43                                                                                                                                 // formated so
  44                                                                                                                                 // just test
  45                                                                                                                                 // against '0'
  46                                                                                                                                 // and potential
  47                                                                                                                                 // . D d
  48                                 switch (source[i]) {
  49                                 case '0':
  50                                 case '.':
  51                                 case 'd':
  52                                 case 'D':
  53                                         break;
  54                                 case 'e':
  55                                 case 'E':
  56                                         break label; // exposant are valid....!
  57                                 default:
  58                                         return;
  59                                 }
  60                         }
  61                 } // error
  62
  63                 constant = Constant.fromValue(value = computedValue.doubleValue());
  64         }
  65
  66         /**
  67          * Code generation for the double literak
  68          *
  69          * @param currentScope
  70          *            net.sourceforge.phpdt.internal.compiler.lookup.BlockScope
  71          * @param codeStream
  72          *            net.sourceforge.phpdt.internal.compiler.codegen.CodeStream
  73          * @param valueRequired
  74          *            boolean
  75          */
  76         // public void generateCode(BlockScope currentScope, CodeStream codeStream,
  77         // boolean valueRequired) {
  78         // int pc = codeStream.position;
  79         // if (valueRequired)
  80         // if ((implicitConversion >> 4) == T_double)
  81         // codeStream.generateInlinedValue(value);
  82         // else
  83         // codeStream.generateConstant(constant, implicitConversion);
  84         // codeStream.recordPositionsFrom(pc, this.sourceStart);
  85         // }
  86         public TypeBinding literalType(BlockScope scope) {
  87                 return DoubleBinding;
  88         }
  89
  90         public void traverse(IAbstractSyntaxTreeVisitor visitor,
  91                         BlockScope blockScope) {
  92                 visitor.visit(this, blockScope);
  93                 visitor.endVisit(this, blockScope);
  94         }
  95 }