java/debugger/impl/src/com/intellij/debugger/engine/evaluation/expression/BoxingEvaluator.java

   1 /*
   2  * Copyright 2000-2010 JetBrains s.r.o.
   3  *
   4  * Licensed under the Apache License, Version 2.0 (the "License");
   5  * you may not use this file except in compliance with the License.
   6  * You may obtain a copy of the License at
   7  *
   8  * http://www.apache.org/licenses/LICENSE-2.0
   9  *
  10  * Unless required by applicable law or agreed to in writing, software
  11  * distributed under the License is distributed on an "AS IS" BASIS,
  12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  13  * See the License for the specific language governing permissions and
  14  * limitations under the License.
  15  */
  16 package com.intellij.debugger.engine.evaluation.expression;
  17
  18 import com.intellij.debugger.engine.DebugProcessImpl;
  19 import com.intellij.debugger.engine.JVMNameUtil;
  20 import com.intellij.debugger.engine.evaluation.EvaluateException;
  21 import com.intellij.debugger.engine.evaluation.EvaluationContextImpl;
  22 import com.sun.jdi.*;
  23 import org.jetbrains.annotations.Nullable;
  24
  25 import java.util.ArrayList;
  26 import java.util.List;
  27
  28 /**
  29  * @author Eugene Zhuravlev
  30  *         Date: Feb 8, 2010
  31  */
  32 public class BoxingEvaluator implements Evaluator{
  33   private final Evaluator myOperand;
  34
  35   public BoxingEvaluator(Evaluator operand) {
  36     myOperand = operand;
  37   }
  38
  39   public Object evaluate(EvaluationContextImpl context) throws EvaluateException {
  40     final Object result = myOperand.evaluate(context);
  41     if (result == null || result instanceof ObjectReference) {
  42       return result;
  43     }
  44
  45     if (result instanceof BooleanValue) {
  46       return convertToWrapper(context, (BooleanValue)result, "java.lang.Boolean");
  47     }
  48     if (result instanceof ByteValue) {
  49       return convertToWrapper(context, (ByteValue)result, "java.lang.Byte");
  50     }
  51     if (result instanceof CharValue) {
  52       return convertToWrapper(context, (CharValue)result, "java.lang.Character");
  53     }
  54     if (result instanceof ShortValue) {
  55       return convertToWrapper(context, (ShortValue)result, "java.lang.Short");
  56     }
  57     if (result instanceof IntegerValue) {
  58       return convertToWrapper(context, (IntegerValue)result, "java.lang.Integer");
  59     }
  60     if (result instanceof LongValue) {
  61       return convertToWrapper(context, (LongValue)result, "java.lang.Long");
  62     }
  63     if (result instanceof FloatValue) {
  64       return convertToWrapper(context, (FloatValue)result, "java.lang.Float");
  65     }
  66     if (result instanceof DoubleValue) {
  67       return convertToWrapper(context, (DoubleValue)result, "java.lang.Double");
  68     }
  69     throw new EvaluateException("Cannot perform boxing conversion for a value of type " + ((Value)result).type().name());
  70   }
  71
  72   @Nullable
  73   public Modifier getModifier() {
  74     return null;
  75   }
  76
  77   private static Value convertToWrapper(EvaluationContextImpl context, PrimitiveValue value, String wrapperTypeName) throws
  78                                                                                                                             EvaluateException {
  79     final DebugProcessImpl process = context.getDebugProcess();
  80     final ClassType wrapperClass = (ClassType)process.findClass(context, wrapperTypeName, null);
  81     final String methodSignature = "(" + JVMNameUtil.getPrimitiveSignature(value.type().name()) + ")L" + wrapperTypeName.replace('.', '/') + ";";
  82
  83     List<Method> methods = wrapperClass.methodsByName("valueOf", methodSignature);
  84     if (methods.size() == 0) { // older JDK version
  85       methods = wrapperClass.methodsByName("<init>", methodSignature);
  86     }
  87     if (methods.size() == 0) {
  88       throw new EvaluateException("Cannot construct wrapper object for value of type " + value.type() + ": Unable to find either valueOf() or constructor method");
  89     }
  90
  91     final Method factoryMethod = methods.get(0);
  92
  93     final ArrayList args = new ArrayList();
  94     args.add(value);
  95
  96     return process.invokeMethod(context, wrapperClass, factoryMethod, args);
  97   }
  98 }