mode.java

java1.6众多例子参考

	methodGen.addException("com.sun.org.apache.xalan.internal.xsltc.TransletException");

	// Create a local variable to hold the current node
	final LocalVariableGen current;
	current = methodGen.addLocalVariable2("current",
					      com.sun.org.apache.bcel.internal.generic.Type.INT,
					      mainIL.getEnd());
	_currentIndex = current.getIndex();

	// Create the "body" instruction list that will eventually hold the
	// code for the entire method (other ILs will be appended).
	final InstructionList body = new InstructionList();
	body.append(NOP);

	// Create an instruction list that contains the default next-node
	// iteration
	final InstructionList ilLoop = new InstructionList();
	ilLoop.append(methodGen.loadIterator());
	ilLoop.append(methodGen.nextNode());
	ilLoop.append(DUP);
	ilLoop.append(new ISTORE(_currentIndex));

	// The body of this code can get very large - large than can be handled
	// by a single IFNE(body.getStart()) instruction - need workaround:
        final BranchHandle ifeq = ilLoop.append(new IFLT(null));
	final BranchHandle loop = ilLoop.append(new GOTO_W(null));
	ifeq.setTarget(ilLoop.append(RETURN)); 	// applyTemplates() ends here!
	final InstructionHandle ihLoop = ilLoop.getStart();

	// Compile default handling of elements (traverse children)
	InstructionList ilRecurse =
	    compileDefaultRecursion(classGen, methodGen, ihLoop);
	InstructionHandle ihRecurse = ilRecurse.getStart();

	// Compile default handling of text/attribute nodes (output text)
	InstructionList ilText =
	    compileDefaultText(classGen, methodGen, ihLoop);
	InstructionHandle ihText = ilText.getStart();

	// Distinguish attribute/element/namespace tests for further processing
	final int[] types = new int[DTM.NTYPES + names.size()];
	for (int i = 0; i < types.length; i++) {
	    types[i] = i;
	}

	// Initialize isAttribute[] and isNamespace[] arrays
	final boolean[] isAttribute = new boolean[types.length];
	final boolean[] isNamespace = new boolean[types.length];
	for (int i = 0; i < names.size(); i++) {
	    final String name = (String)names.elementAt(i);
	    isAttribute[i + DTM.NTYPES] = isAttributeName(name);
	    isNamespace[i + DTM.NTYPES] = isNamespaceName(name);
	}

	// Compile all templates - regardless of pattern type
	compileTemplates(classGen, methodGen, ihLoop);

	// Handle template with explicit "*" pattern
	final TestSeq elemTest = _testSeq[DTM.ELEMENT_NODE];
	InstructionHandle ihElem = ihRecurse;
	if (elemTest != null)
	    ihElem = elemTest.compile(classGen, methodGen, ihRecurse);

	// Handle template with explicit "@*" pattern
	final TestSeq attrTest = _testSeq[DTM.ATTRIBUTE_NODE];
	InstructionHandle ihAttr = ihText;
	if (attrTest != null)
	    ihAttr = attrTest.compile(classGen, methodGen, ihAttr);

	// Do tests for id() and key() patterns first
	InstructionList ilKey = null;
	if (_idxTestSeq != null) {
	    loop.setTarget(_idxTestSeq.compile(classGen, methodGen, body.getStart()));
	    ilKey = _idxTestSeq.getInstructionList();
	}
	else {
	    loop.setTarget(body.getStart());
	}

	// If there is a match on node() we need to replace ihElem
	// and ihText if the priority of node() is higher
	if (_childNodeTestSeq != null) {
	    // Compare priorities of node() and "*"
	    double nodePrio = _childNodeTestSeq.getPriority();
	    int    nodePos  = _childNodeTestSeq.getPosition();
	    double elemPrio = (0 - Double.MAX_VALUE);
	    int    elemPos  = Integer.MIN_VALUE;

	    if (elemTest != null) {
		elemPrio = elemTest.getPriority();
		elemPos  = elemTest.getPosition();
	    }
	    if (elemPrio == Double.NaN || elemPrio < nodePrio || 
		(elemPrio == nodePrio && elemPos < nodePos)) 
	    {
		ihElem = _childNodeTestSeq.compile(classGen, methodGen, ihLoop);
	    }

	    // Compare priorities of node() and text()
	    final TestSeq textTest = _testSeq[DTM.TEXT_NODE];
	    double textPrio = (0 - Double.MAX_VALUE);
	    int    textPos  = Integer.MIN_VALUE;

	    if (textTest != null) {
		textPrio = textTest.getPriority();
		textPos  = textTest.getPosition();
	    }
	    if (textPrio == Double.NaN || textPrio < nodePrio ||
	        (textPrio == nodePrio && textPos < nodePos)) 
	    {
		ihText = _childNodeTestSeq.compile(classGen, methodGen, ihLoop);
		_testSeq[DTM.TEXT_NODE] = _childNodeTestSeq;
	    }
	}

	// Handle templates with "ns:*" pattern
	InstructionHandle elemNamespaceHandle = ihElem;
	InstructionList nsElem = compileNamespaces(classGen, methodGen,
						   isNamespace, isAttribute,
						   false, ihElem);
	if (nsElem != null) elemNamespaceHandle = nsElem.getStart();

	// Handle templates with "ns:@*" pattern
	InstructionHandle attrNamespaceHandle = ihAttr;
	InstructionList nsAttr = compileNamespaces(classGen, methodGen,
						   isNamespace, isAttribute,
						   true, ihAttr);
	if (nsAttr != null) attrNamespaceHandle = nsAttr.getStart();

	// Handle templates with "ns:elem" or "ns:@attr" pattern
	final InstructionHandle[] targets = new InstructionHandle[types.length];
	for (int i = DTM.NTYPES; i < targets.length; i++) {
	    final TestSeq testSeq = _testSeq[i];
	    // Jump straight to namespace tests ?
	    if (isNamespace[i]) {
		if (isAttribute[i])
		    targets[i] = attrNamespaceHandle;
		else
		    targets[i] = elemNamespaceHandle;
	    }
	    // Test first, then jump to namespace tests
	    else if (testSeq != null) {
		if (isAttribute[i])
		    targets[i] = testSeq.compile(classGen, methodGen,
						 attrNamespaceHandle);
		else
		    targets[i] = testSeq.compile(classGen, methodGen,
						 elemNamespaceHandle);
	    }
	    else {
		targets[i] = ihLoop;
	    }
	}


	// Handle pattern with match on root node - default: traverse children
	targets[DTM.ROOT_NODE] = _rootPattern != null
	    ? getTemplateInstructionHandle(_rootPattern.getTemplate())
	    : ihRecurse;

        // Handle pattern with match on root node - default: traverse children
	targets[DTM.DOCUMENT_NODE] = _rootPattern != null
	    ? getTemplateInstructionHandle(_rootPattern.getTemplate())
	    : ihRecurse;

	// Handle any pattern with match on text nodes - default: output text
	targets[DTM.TEXT_NODE] = _testSeq[DTM.TEXT_NODE] != null
	    ? _testSeq[DTM.TEXT_NODE].compile(classGen, methodGen, ihText)
	    : ihText;

	// This DOM-type is not in use - default: process next node
	targets[DTM.NAMESPACE_NODE] = ihLoop;

	// Match unknown element in DOM - default: check for namespace match
	targets[DTM.ELEMENT_NODE] = elemNamespaceHandle;

	// Match unknown attribute in DOM - default: check for namespace match
	targets[DTM.ATTRIBUTE_NODE] = attrNamespaceHandle;

	// Match on processing instruction - default: process next node
	InstructionHandle ihPI = ihLoop;
	if (_childNodeTestSeq != null) ihPI = ihElem;
	if (_testSeq[DTM.PROCESSING_INSTRUCTION_NODE] != null)
	    targets[DTM.PROCESSING_INSTRUCTION_NODE] =
		_testSeq[DTM.PROCESSING_INSTRUCTION_NODE].
		compile(classGen, methodGen, ihPI);
	else
	    targets[DTM.PROCESSING_INSTRUCTION_NODE] = ihPI;
	
	// Match on comments - default: process next node
	InstructionHandle ihComment = ihLoop;
	if (_childNodeTestSeq != null) ihComment = ihElem;
	targets[DTM.COMMENT_NODE] = _testSeq[DTM.COMMENT_NODE] != null
	    ? _testSeq[DTM.COMMENT_NODE].compile(classGen, methodGen, ihComment)
	    : ihComment;
	    
	    // This DOM-type is not in use - default: process next node
	targets[DTM.CDATA_SECTION_NODE] = ihLoop;

	// This DOM-type is not in use - default: process next node
	targets[DTM.DOCUMENT_FRAGMENT_NODE] = ihLoop;
	
	// This DOM-type is not in use - default: process next node
	targets[DTM.DOCUMENT_TYPE_NODE] = ihLoop;

	// This DOM-type is not in use - default: process next node
	targets[DTM.ENTITY_NODE] = ihLoop;

	// This DOM-type is not in use - default: process next node
	targets[DTM.ENTITY_REFERENCE_NODE] = ihLoop;
	
	// This DOM-type is not in use - default: process next node
	targets[DTM.NOTATION_NODE] = ihLoop;


	// Now compile test sequences for various match patterns:
	for (int i = DTM.NTYPES; i < targets.length; i++) {
	    final TestSeq testSeq = _testSeq[i];
	    // Jump straight to namespace tests ?
	    if ((testSeq == null) || (isNamespace[i])) {
		if (isAttribute[i])
		    targets[i] = attrNamespaceHandle;
		else
		    targets[i] = elemNamespaceHandle;
	    }
	    // Match on node type
	    else {
		if (isAttribute[i])
		    targets[i] = testSeq.compile(classGen, methodGen,
						 attrNamespaceHandle);
		else
		    targets[i] = testSeq.compile(classGen, methodGen,
						 elemNamespaceHandle);
	    }
	}

	if (ilKey != null) body.insert(ilKey);

	// Append first code in applyTemplates() - get type of current node
	final int getType = cpg.addInterfaceMethodref(DOM_INTF,
						      "getExpandedTypeID",
                                                      "(I)I");
	body.append(methodGen.loadDOM());
	body.append(new ILOAD(_currentIndex));
	body.append(new INVOKEINTERFACE(getType, 2));

	// Append switch() statement - main dispatch loop in applyTemplates()
	InstructionHandle disp = body.append(new SWITCH(types, targets, ihLoop));

	// Append all the "case:" statements
	appendTestSequences(body);
	// Append the actual template code
	appendTemplateCode(body);

	// Append NS:* node tests (if any)
	if (nsElem != null) body.append(nsElem);
	// Append NS:@* node tests (if any)
	if (nsAttr != null) body.append(nsAttr);

	// Append default action for element and root nodes
	body.append(ilRecurse);
	// Append default action for text and attribute nodes
	body.append(ilText);

	// putting together constituent instruction lists
	mainIL.append(new GOTO_W(ihLoop));
	mainIL.append(body);
	// fall through to ilLoop
	mainIL.append(ilLoop);

	peepHoleOptimization(methodGen);
	methodGen.stripAttributes(true);
	
	methodGen.setMaxLocals();
	methodGen.setMaxStack();
	methodGen.removeNOPs();
	classGen.addMethod(methodGen.getMethod());

	// Compile method(s) for <xsl:apply-imports/> for this mode
	if (_importLevels != null) {
	    Enumeration levels = _importLevels.keys();
	    while (levels.hasMoreElements()) {
		Integer max = (Integer)levels.nextElement();
		Integer min = (Integer)_importLevels.get(max);
		compileApplyImports(classGen, min.intValue(), max.intValue());
	    }
	}
    }

    private void compileTemplateCalls(ClassGenerator classGen,
				      MethodGenerator methodGen,
				      InstructionHandle next, int min, int max){
        Enumeration templates = _neededTemplates.keys();
	while (templates.hasMoreElements()) {
	    final Template template = (Template)templates.nextElement();
	    final int prec = template.getImportPrecedence();
	    if ((prec >= min) && (prec < max)) {
		if (template.hasContents()) {
		    InstructionList til = template.compile(classGen, methodGen);
		    til.append(new GOTO_W(next));
		    _templateILs.put(template, til);
		    _templateIHs.put(template, til.getStart());
		}
		else {
		    // empty template
		    _templateIHs.put(template, next);
		}
	    }
	}
    }


    public void compileApplyImports(ClassGenerator classGen, int min, int max) {
	final XSLTC xsltc = classGen.getParser().getXSLTC();
	final ConstantPoolGen cpg = classGen.getConstantPool();
	final Vector names      = xsltc.getNamesIndex();

	// Clear some datastructures
	_namedTemplates = new Hashtable();
	_neededTemplates = new Hashtable();
	_templateIHs = new Hashtable();
	_templateILs = new Hashtable();
	_patternGroups = new Vector[32];
	_rootPattern = null;

	// IMPORTANT: Save orignal & complete set of templates!!!!
	Vector oldTemplates = _templates;

	// Gather templates that are within the scope of this import
	_templates = new Vector();
	final Enumeration templates = oldTemplates.elements();
	while (templates.hasMoreElements()) {
	    final Template template = (Template)templates.nextElement();
	    final int prec = template.getImportPrecedence();
	    if ((prec >= min) && (prec < max)) addTemplate(template);
	}

	// Process all patterns from those templates
	processPatterns(_keys);

	// Create the applyTemplates() method
	final com.sun.org.apache.bcel.internal.generic.Type[] argTypes =
	    new com.sun.org.apache.bcel.internal.generic.Type[4];
	argTypes[0] = Util.getJCRefType(DOM_INTF_SIG);
	argTypes[1] = Util.getJCRefType(NODE_ITERATOR_SIG);
	argTypes[2] = Util.getJCRefType(TRANSLET_OUTPUT_SIG);
	argTypes[3] = com.sun.org.apache.bcel.internal.generic.Type.INT;

	final String[] argNames = new String[4];
	argNames[0] = DOCUMENT_PNAME;
	argNames[1] = ITERATOR_PNAME;
	argNames[2] = TRANSLET_OUTPUT_PNAME;
	argNames[3] = NODE_PNAME;

	final InstructionList mainIL = new InstructionList();
	final MethodGenerator methodGen =
	    new MethodGenerator(ACC_PUBLIC | ACC_FINAL, 
				com.sun.org.apache.bcel.internal.generic.Type.VOID,
				argTypes, argNames, functionName()+'_'+max,
				getClassName(), mainIL,
				classGen.getConstantPool());
	methodGen.addException("com.sun.org.apache.xalan.internal.xsltc.TransletException");

	// Create the local variable to hold the current node
	final LocalVariableGen current;
	current = methodGen.addLocalVariable2("current",
					      com.sun.org.apache.bcel.internal.generic.Type.INT,
					      mainIL.getEnd());
	_currentIndex = current.getIndex();

    mainIL.append(new ILOAD(methodGen.getLocalIndex(NODE_PNAME)));
    mainIL.append(new ISTORE(_currentIndex));
    
	// Create the "body" instruction list that will eventually hold the
	// code for the entire method (other ILs will be appended).
	final InstructionList body = new InstructionList();
	body.append(NOP);

	// Create an instruction list that contains the default next-node
	// iteration
	final InstructionList ilLoop = new InstructionList();