| /* |
| * @(#)$Id$ |
| * |
| * The Apache Software License, Version 1.1 |
| * |
| * |
| * Copyright (c) 2001 The Apache Software Foundation. All rights |
| * reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions |
| * are met: |
| * |
| * 1. Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * |
| * 2. Redistributions in binary form must reproduce the above copyright |
| * notice, this list of conditions and the following disclaimer in |
| * the documentation and/or other materials provided with the |
| * distribution. |
| * |
| * 3. The end-user documentation included with the redistribution, |
| * if any, must include the following acknowledgment: |
| * "This product includes software developed by the |
| * Apache Software Foundation (http://www.apache.org/)." |
| * Alternately, this acknowledgment may appear in the software itself, |
| * if and wherever such third-party acknowledgments normally appear. |
| * |
| * 4. The names "Xalan" and "Apache Software Foundation" must |
| * not be used to endorse or promote products derived from this |
| * software without prior written permission. For written |
| * permission, please contact apache@apache.org. |
| * |
| * 5. Products derived from this software may not be called "Apache", |
| * nor may "Apache" appear in their name, without prior written |
| * permission of the Apache Software Foundation. |
| * |
| * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED |
| * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
| * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE |
| * DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR |
| * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, |
| * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT |
| * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF |
| * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND |
| * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, |
| * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT |
| * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF |
| * SUCH DAMAGE. |
| * ==================================================================== |
| * |
| * This software consists of voluntary contributions made by many |
| * individuals on behalf of the Apache Software Foundation and was |
| * originally based on software copyright (c) 2001, Sun |
| * Microsystems., http://www.sun.com. For more |
| * information on the Apache Software Foundation, please see |
| * <http://www.apache.org/>. |
| * |
| * @author G. Todd Miller |
| * @author Santiago Pericas-Geertsen |
| * |
| */ |
| |
| package org.apache.xalan.xsltc.compiler; |
| |
| import java.util.Vector; |
| import java.lang.reflect.Modifier; |
| import java.lang.reflect.Method; |
| import org.apache.xalan.xsltc.compiler.util.Type; |
| import org.apache.bcel.generic.*; |
| import org.apache.xalan.xsltc.compiler.util.*; |
| import org.apache.xalan.xsltc.runtime.TransletLoader; |
| |
| final class FunctionAvailableCall extends FunctionCall { |
| |
| private boolean _isFunctionAvailable = false; |
| private Expression _arg; |
| private String _namespaceOfFunct =null; |
| private String _nameOfFunct =null; |
| |
| |
| /** |
| * 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. The test for availability considers |
| * internal xsl functions such as 'floor' as well as external |
| * Java functions, such as 'java.lang.Math.sin'. The case of |
| * external functions is handled here, the case of internal |
| * functions is handled in getResult. |
| */ |
| 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 ((_namespaceOfFunct != null) && |
| (!_namespaceOfFunct.equals(Constants.EMPTYSTRING))) |
| { |
| // the function is external, such as a java function |
| _isFunctionAvailable = hasMethods(); |
| } |
| // the case of internal function is handled in getResult. |
| } |
| // case where _arg is not instanceof LiteralExpr can not be handled. |
| } |
| |
| /** |
| * 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 { |
| // may be already set |
| if ( _type != null ) { |
| return _type; |
| } |
| if (_arg instanceof LiteralExpr) { |
| _type = Type.Boolean; |
| return Type.Boolean; |
| } |
| ErrorMsg err = new ErrorMsg(ErrorMsg.NEED_LITERAL_ERR, |
| "function-available", this); |
| throw new TypeCheckError(err); |
| } |
| |
| /** |
| * (For ext. java functions only) |
| * Parses the argument to function-available to extract the package |
| * qualified class name, for example, given the argument |
| * 'java:java.lang.Math.sin', getClassName would return |
| * 'java.lang.Math'. See also 'getMethodName'. |
| */ |
| private String getClassName(String argValue){ |
| int colonSep = argValue.indexOf(":"); |
| if (colonSep != -1) { |
| argValue = argValue.substring(colonSep+1); |
| } |
| int lastDot = argValue.lastIndexOf("."); |
| if (lastDot != -1) { |
| argValue = argValue.substring(0, lastDot); |
| } |
| return argValue; |
| } |
| |
| /** |
| * (For ext. java functions only) |
| * Parses the argument to function-available |
| * to extract the method name, for example, given the argument |
| * 'java.lang.Math.sin', getMethodName would return 'sin'. |
| */ |
| private String getMethodName(String argValue){ |
| int lastDot = argValue.lastIndexOf("."); |
| if (lastDot != -1) { |
| argValue = argValue.substring(lastDot+1); |
| } |
| return argValue; |
| } |
| |
| /** |
| * (For java external functions only) |
| * Creates a full package qualified |
| * function name taking into account the namespace and the |
| * function name derived from the argument passed to function-available. |
| * For example, given a name of 'java:java.lang.Math.sin' and a |
| * namespace of 'http://xml.apache.org/xalan/xsltc/java' this routine |
| * constructs a uri and then derives the class name |
| * 'java.lang.Math.sin' from the uri. The uri in this example would |
| * be 'http://xml.apache.org/xalan/xsltc/java.java.lang.Math.sin' |
| */ |
| private String getExternalFunctionName() { |
| int colonIndex = _nameOfFunct.indexOf(":"); |
| String uri = _namespaceOfFunct + |
| "." + _nameOfFunct.substring(colonIndex+1); |
| try{ |
| return getClassNameFromUri(uri); |
| } catch (TypeCheckError e) { |
| return null; |
| } |
| } |
| |
| /** |
| * for external java functions only: reports on whether or not |
| * the specified method is found in the specifed class. |
| */ |
| private boolean hasMethods() { |
| |
| LiteralExpr arg = (LiteralExpr)_arg; |
| final String externalFunctName = getExternalFunctionName(); |
| if (externalFunctName == null) { |
| return false; |
| } |
| final String className = getClassName(externalFunctName); |
| |
| if (_namespaceOfFunct.startsWith(JAVA_EXT_XSLTC) || |
| _namespaceOfFunct.startsWith(JAVA_EXT_XALAN)) { |
| try { |
| TransletLoader loader = new TransletLoader(); |
| final Class clazz = loader.loadClass(className); |
| |
| if (clazz == null) { |
| final ErrorMsg msg = |
| new ErrorMsg(ErrorMsg.CLASS_NOT_FOUND_ERR, className); |
| getParser().reportError(Constants.ERROR, msg); |
| } |
| else { |
| final String methodName = getMethodName(externalFunctName); |
| final Method[] methods = clazz.getDeclaredMethods(); |
| |
| 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) { |
| final ErrorMsg msg = |
| new ErrorMsg(ErrorMsg.CLASS_NOT_FOUND_ERR, className); |
| getParser().reportError(Constants.ERROR, msg); |
| } |
| } |
| return false; |
| } |
| |
| /** |
| * reports on whether the function specified in the argument to |
| * xslt function 'function-available' was found. |
| */ |
| public boolean getResult() { |
| if ((_namespaceOfFunct == null) || |
| (_namespaceOfFunct.equals(Constants.EMPTYSTRING))) |
| { |
| // no namespace, so the function is an internal xslt function. |
| final Parser parser = getParser(); |
| _isFunctionAvailable = parser.functionSupported(_nameOfFunct); |
| } |
| return _isFunctionAvailable; |
| } |
| |
| |
| /** |
| * 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())); |
| } |
| |
| } |
