| /* |
| * reserved comment block |
| * DO NOT REMOVE OR ALTER! |
| */ |
| /* |
| * Copyright 2001-2004 The Apache Software Foundation. |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| /* |
| * $Id: FunctionAvailableCall.java,v 1.2.4.1 2005/09/01 15:30:25 pvedula Exp $ |
| */ |
| |
| package com.sun.org.apache.xalan.internal.xsltc.compiler; |
| |
| import java.lang.reflect.Method; |
| import java.lang.reflect.Modifier; |
| import java.util.Vector; |
| |
| import com.sun.org.apache.bcel.internal.generic.ConstantPoolGen; |
| import com.sun.org.apache.bcel.internal.generic.PUSH; |
| import com.sun.org.apache.xalan.internal.xsltc.compiler.util.ClassGenerator; |
| import com.sun.org.apache.xalan.internal.xsltc.compiler.util.ErrorMsg; |
| import com.sun.org.apache.xalan.internal.xsltc.compiler.util.MethodGenerator; |
| import com.sun.org.apache.xalan.internal.xsltc.compiler.util.Type; |
| import com.sun.org.apache.xalan.internal.xsltc.compiler.util.TypeCheckError; |
| import com.sun.org.apache.xalan.internal.xsltc.compiler.util.Util; |
| import com.sun.org.apache.xalan.internal.utils.ObjectFactory; |
| |
| /** |
| * @author G. Todd Miller |
| * @author Santiago Pericas-Geertsen |
| */ |
| final class FunctionAvailableCall extends FunctionCall { |
| |
| private Expression _arg; |
| private String _nameOfFunct = null; |
| private String _namespaceOfFunct = null; |
| private boolean _isFunctionAvailable = false; |
| |
| /** |
| * Constructs a FunctionAvailableCall FunctionCall. Takes the |
| * function name qname, for example, 'function-available', and |
| * a list of arguments where the arguments must be instances of |
| * LiteralExpression. |
| */ |
| public FunctionAvailableCall(QName fname, Vector arguments) { |
| super(fname, arguments); |
| _arg = (Expression)arguments.elementAt(0); |
| _type = null; |
| |
| if (_arg instanceof LiteralExpr) { |
| LiteralExpr arg = (LiteralExpr) _arg; |
| _namespaceOfFunct = arg.getNamespace(); |
| _nameOfFunct = arg.getValue(); |
| |
| if (!isInternalNamespace()) { |
| _isFunctionAvailable = hasMethods(); |
| } |
| } |
| } |
| |
| /** |
| * Argument of function-available call must be literal, typecheck |
| * returns the type of function-available to be boolean. |
| */ |
| public Type typeCheck(SymbolTable stable) throws TypeCheckError { |
| if (_type != null) { |
| return _type; |
| } |
| if (_arg instanceof LiteralExpr) { |
| return _type = Type.Boolean; |
| } |
| ErrorMsg err = new ErrorMsg(ErrorMsg.NEED_LITERAL_ERR, |
| "function-available", this); |
| throw new TypeCheckError(err); |
| } |
| |
| /** |
| * Returns an object representing the compile-time evaluation |
| * of an expression. We are only using this for function-available |
| * and element-available at this time. |
| */ |
| public Object evaluateAtCompileTime() { |
| return getResult() ? Boolean.TRUE : Boolean.FALSE; |
| } |
| |
| /** |
| * for external java functions only: reports on whether or not |
| * the specified method is found in the specifed class. |
| */ |
| private boolean hasMethods() { |
| |
| // Get the class name from the namespace uri |
| String className = getClassNameFromUri(_namespaceOfFunct); |
| |
| // Get the method name from the argument to function-available |
| String methodName = null; |
| int colonIndex = _nameOfFunct.indexOf(':'); |
| if (colonIndex > 0) { |
| String functionName = _nameOfFunct.substring(colonIndex+1); |
| int lastDotIndex = functionName.lastIndexOf('.'); |
| if (lastDotIndex > 0) { |
| methodName = functionName.substring(lastDotIndex+1); |
| if (className != null && className.length() != 0) |
| className = className + "." + functionName.substring(0, lastDotIndex); |
| else |
| className = functionName.substring(0, lastDotIndex); |
| } |
| else |
| methodName = functionName; |
| } |
| else |
| methodName = _nameOfFunct; |
| |
| if (className == null || methodName == null) { |
| return false; |
| } |
| |
| // Replace the '-' characters in the method name |
| if (methodName.indexOf('-') > 0) |
| methodName = replaceDash(methodName); |
| |
| try { |
| final Class clazz = ObjectFactory.findProviderClass(className, true); |
| |
| if (clazz == null) { |
| return false; |
| } |
| |
| final Method[] methods = clazz.getMethods(); |
| |
| for (int i = 0; i < methods.length; i++) { |
| final int mods = methods[i].getModifiers(); |
| |
| if (Modifier.isPublic(mods) && Modifier.isStatic(mods) |
| && methods[i].getName().equals(methodName)) |
| { |
| return true; |
| } |
| } |
| } |
| catch (ClassNotFoundException e) { |
| return false; |
| } |
| return false; |
| } |
| |
| /** |
| * Reports on whether the function specified in the argument to |
| * xslt function 'function-available' was found. |
| */ |
| public boolean getResult() { |
| if (_nameOfFunct == null) { |
| return false; |
| } |
| |
| if (isInternalNamespace()) { |
| final Parser parser = getParser(); |
| _isFunctionAvailable = |
| parser.functionSupported(Util.getLocalName(_nameOfFunct)); |
| } |
| return _isFunctionAvailable; |
| } |
| |
| /** |
| * Return true if the namespace uri is null or it is the XSLTC translet uri. |
| */ |
| private boolean isInternalNamespace() { |
| return (_namespaceOfFunct == null || |
| _namespaceOfFunct.equals(EMPTYSTRING) || |
| _namespaceOfFunct.equals(TRANSLET_URI)); |
| } |
| |
| /** |
| * Calls to 'function-available' are resolved at compile time since |
| * the namespaces declared in the stylsheet are not available at run |
| * time. Consequently, arguments to this function must be literals. |
| */ |
| public void translate(ClassGenerator classGen, MethodGenerator methodGen) { |
| final ConstantPoolGen cpg = classGen.getConstantPool(); |
| methodGen.getInstructionList().append(new PUSH(cpg, getResult())); |
| } |
| |
| } |