taganalyzer.java

来自「RESIN 3.2 最新源码」· Java 代码 · 共 802 行 · 第 1/2 页

   */
  static class AbstractTagMethodAnalyzer extends Analyzer
  {
    private AnalyzedTag _tag;
    
    private boolean _hasCode;
    
    private int _count = 0;
    private int _value = -1;

    protected AbstractTagMethodAnalyzer(AnalyzedTag tag)
    {
      _tag = tag;
    }

    protected boolean hasCode()
    {
      return _hasCode;
    }

    protected void setHasCode()
    {
      _hasCode = true;
    }

    public void analyze(CodeVisitor visitor)
    {
      int count = _count++;

      switch (visitor.getOpcode()) {
      case CodeVisitor.IRETURN:
	if (count != 1)
	  _hasCode = true;

	addReturnValue(_value);
	break;

      case CodeVisitor.ICONST_M1:
      case CodeVisitor.ICONST_0:
      case CodeVisitor.ICONST_1:
      case CodeVisitor.ICONST_2:
      case CodeVisitor.ICONST_3:
      case CodeVisitor.ICONST_4:
      case CodeVisitor.ICONST_5:
	if (count != 0)
	  _hasCode = true;
	    
	_value = visitor.getOpcode() - CodeVisitor.ICONST_0;
	break;

      case CodeVisitor.BIPUSH:
	if (count != 0)
	  _hasCode = true;
	
	_value = visitor.getByteArg();
	break;

      case CodeVisitor.SIPUSH:
	if (count != 0)
	  _hasCode = true;
	
	_value = visitor.getShortArg();
	break;

      case CodeVisitor.ALOAD_0:
	if (count != 0)
	  _hasCode = true;
	break;

      case CodeVisitor.INVOKEVIRTUAL:
      case CodeVisitor.INVOKESPECIAL:
	{
	  // matching int methods have an extra opcode for 'this'
	  if (count != 1)
	    _hasCode = true;
	  
	  _value = -1;
	
	  int index = visitor.getShortArg();
	  JavaClass jClass = visitor.getJavaClass();

	  MethodRefConstant methodRef
	    = jClass.getConstantPool().getMethodRef(index);

	  IntMethodAnalyzer value = analyzeIntMethod(_tag,
						     methodRef.getName(),
						     methodRef.getType());

	  if (value != null) {
	    _value = value.getValue();

	    // reset count since the subcall checks for side-effect code
	    if (count == 1)
	      _count = 1;

	    if (value.hasCode()) {
	      _hasCode = true;
	    }
	  }
	  else {
	    _hasCode = true;
	  }
	}
	break;
	  
      default:
	_hasCode = true;
	_value = -1;
	break;
      }
    }

    protected void addReturnValue(int value)
    {
    }
  }
  
  /**
   * Callback analyzing the doStartTag method.
   */
  static class StartAnalyzer extends AbstractTagMethodAnalyzer {
    private boolean _hasSkip;
    private boolean _hasInclude;
    private boolean _hasBuffered;

    StartAnalyzer(AnalyzedTag tag)
    {
      super(tag);
    }

    @Override
    protected void addReturnValue(int value)
    {
      if (value == Tag.SKIP_BODY)
	_hasSkip = true;
      else if (value == Tag.EVAL_BODY_INCLUDE)
	_hasInclude = true;
      else if (value == BodyTag.EVAL_BODY_BUFFERED)
	_hasBuffered = true;
      else {
	_hasSkip = true;
	_hasInclude = true;
	_hasBuffered = true;
	setHasCode();
      }
    }

    public void complete(AnalyzedTag tag)
    {
      tag.setDoStart(hasCode());
      tag.setStartReturnsSkip(_hasSkip);
      tag.setStartReturnsInclude(_hasInclude);
      tag.setStartReturnsBuffered(_hasBuffered);
    }
  }
  
  /**
   * Callback analyzing the doEndTag method.
   */
  static class EndAnalyzer extends AbstractTagMethodAnalyzer {
    private boolean _hasSkip;
    private boolean _hasEval;

    EndAnalyzer(AnalyzedTag tag)
    {
      super(tag);
    }

    @Override
    protected void addReturnValue(int value)
    {
      if (value == Tag.SKIP_PAGE)
	_hasSkip = true;
      else if (value == Tag.EVAL_PAGE)
	_hasEval = true;
      else {
	_hasSkip = true;
	_hasEval = true;
	setHasCode();
      }
    }

    public void complete(AnalyzedTag tag)
    {
      tag.setDoEnd(hasCode());
      tag.setEndReturnsSkip(_hasSkip);
      tag.setEndReturnsEval(_hasEval);
    }

    public String toString()
    {
      return (getClass().getSimpleName() + "[end:" + hasCode()
	      + ",skip:" + _hasSkip + ",eval:" + _hasEval + "]");
    }
  }

  /**
   * Callback analyzing the doAfterBody method.
   */
  static class AfterAnalyzer extends AbstractTagMethodAnalyzer
  {
    private boolean _hasAgain;

    AfterAnalyzer(AnalyzedTag tag)
    {
      super(tag);
    }

    @Override
    protected void addReturnValue(int value)
    {
      if (value == IterationTag.EVAL_BODY_AGAIN)
	_hasAgain = true;
      else if (value == IterationTag.SKIP_BODY
	       || value == BodyTag.SKIP_PAGE) {
      }
      else {
	_hasAgain = true;
	setHasCode();
      }
    }

    public void complete(AnalyzedTag tag)
    {
      tag.setDoAfter(hasCode());
      tag.setAfterReturnsAgain(_hasAgain);
    }
  }

  /**
   * Callback analyzing the doInitBody method.
   */
  static class InitAnalyzer extends Analyzer {
    private boolean _hasCode;

    private int _count = 0;

    public void analyze(CodeVisitor visitor)
    {
      int count = _count++;
      
      switch (visitor.getOpcode()) {
      case CodeVisitor.RETURN:
	if (count != 0)
	  _hasCode = true;
	break;

      default:
	_hasCode = true;
	break;
      }
    }

    public void complete(AnalyzedTag tag)
    {
      tag.setDoInit(_hasCode);
    }
  }

  /**
   * Callback analyzing the doCatch method.
   */
  static class CatchAnalyzer extends Analyzer {
    private boolean _hasCode;

    private int _count = 0;

    public void analyze(CodeVisitor visitor)
    {
      int count = _count++;
      
      switch (visitor.getOpcode()) {
      case CodeVisitor.RETURN:
	if (count != 0)
	  _hasCode = true;
	break;

      default:
	_hasCode = true;
	break;
      }
    }

    public void complete(AnalyzedTag tag)
    {
      tag.setDoCatch(_hasCode);
    }
  }

  /**
   * Callback analyzing the doFinally method.
   */
  static class FinallyAnalyzer extends Analyzer {
    private boolean _hasCode;

    private int _count = 0;

    public void analyze(CodeVisitor visitor)
    {
      int count = _count++;
      
      switch (visitor.getOpcode()) {
      case CodeVisitor.RETURN:
	if (count != 0)
	  _hasCode = true;
	break;

      default:
	_hasCode = true;
	break;
      }
    }

    public void complete(AnalyzedTag tag)
    {
      tag.setDoFinally(_hasCode);
    }
  }
  
  /**
   * Callback analyzing a zero-arg int method (for constant values).
   */
  static class IntMethodAnalyzer extends Analyzer
  {
    private int _count = 0;
    private int _value = -1;

    private boolean _hasCode;
    
    private int _resultValue = -1;
    private int _resultValueCount = 0;

    public boolean isUnique()
    {
      return _resultValueCount == 1;
    }

    public boolean hasCode()
    {
      return _hasCode;
    }

    public int getValue()
    {
      return _resultValue;
    }

    public void analyze(CodeVisitor visitor)
    {
      int count = _count++;
      
      switch (visitor.getOpcode()) {
      case CodeVisitor.IRETURN:
	if (count > 1)
	  _hasCode = true;
	
	if (_resultValueCount == 0) {
	  _resultValue = _value;
	  _resultValueCount = 1;
	}
	else if (_value != _resultValue)
	  _resultValueCount++;
	break;

      case CodeVisitor.ICONST_M1:
      case CodeVisitor.ICONST_0:
      case CodeVisitor.ICONST_1:
      case CodeVisitor.ICONST_2:
      case CodeVisitor.ICONST_3:
      case CodeVisitor.ICONST_4:
      case CodeVisitor.ICONST_5:
	if (count > 0)
	  _hasCode = true;
	
	_value = visitor.getOpcode() - CodeVisitor.ICONST_0;
	break;

      case CodeVisitor.BIPUSH:
	if (count > 0)
	  _hasCode = true;
	
	_value = visitor.getByteArg();
	break;

      case CodeVisitor.SIPUSH:
	if (count > 0)
	  _hasCode = true;
	
	_value = visitor.getShortArg();
	break;
	  
      default:
	_hasCode = true;
	
	_value = -1;
	break;
      }
    }
  }
}