- /*
- * The Apache Software License, Version 1.1
- *
- * Copyright (c) 1999 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 acknowlegement:
- * "This product includes software developed by the
- * Apache Software Foundation (http://www.apache.org/)."
- * Alternately, this acknowlegement may appear in the software itself,
- * if and wherever such third-party acknowlegements normally appear.
- *
- * 4. The names "The Jakarta Project", "Tomcat", 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 names without prior written
- * permission of the Apache Group.
- *
- * 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. For more
- * information on the Apache Software Foundation, please see
- * <http://www.apache.org/>.
- *
- */
-
- package org.apache.commons.el;
-
- import java.util.List;
- import java.util.Map;
- import java.util.Iterator;
- import java.lang.reflect.*;
- import javax.servlet.jsp.el.ELException;
- import javax.servlet.jsp.el.VariableResolver;
- import javax.servlet.jsp.el.FunctionMapper;
-
- /**
- *
- * <p>Represents a function call.</p>
- *
- * @author Shawn Bayern (in the style of Nathan's other classes)
- **/
-
- public class FunctionInvocation
- extends Expression
- {
- //-------------------------------------
- // Properties
- //-------------------------------------
- // property index
-
- private String functionName;
- private List argumentList;
- public String getFunctionName() { return functionName; }
- public void setFunctionName(String f) { functionName = f; }
- public List getArgumentList() { return argumentList; }
- public void setArgumentList(List l) { argumentList = l; }
-
- //-------------------------------------
- /**
- * Constructor
- **/
- public FunctionInvocation (String functionName, List argumentList)
- {
- this.functionName = functionName;
- this.argumentList = argumentList;
- }
-
- //-------------------------------------
- // Expression methods
- //-------------------------------------
- /**
- * Returns the expression in the expression language syntax
- **/
- public String getExpressionString ()
- {
- StringBuffer b = new StringBuffer();
- b.append(functionName);
- b.append("(");
- Iterator i = argumentList.iterator();
- while (i.hasNext()) {
- b.append(((Expression) i.next()).getExpressionString());
- if (i.hasNext())
- b.append(", ");
- }
- b.append(")");
- return b.toString();
- }
-
-
- //-------------------------------------
- /**
- *
- * Evaluates by looking up the name in the VariableResolver
- **/
- public Object evaluate (VariableResolver pResolver,
- FunctionMapper functions,
- Logger pLogger)
- throws ELException
- {
-
- // if the Map is null, then the function is invalid
- if (functions == null)
- pLogger.logError(Constants.UNKNOWN_FUNCTION, functionName);
-
- // normalize function name
- String prefix = null;
- String localName = null;
- int index = functionName.indexOf( ':' );
- if (index == -1) {
- prefix = "";
- localName = functionName;
- } else {
- prefix = functionName.substring( 0, index );
- localName = functionName.substring( index + 1 );
- }
-
- // ensure that the function's name is mapped
- Method target = (Method) functions.resolveFunction(prefix, localName);
- if (target == null)
- pLogger.logError(Constants.UNKNOWN_FUNCTION, functionName);
-
- // ensure that the number of arguments matches the number of parameters
- Class[] params = target.getParameterTypes();
- if (params.length != argumentList.size())
- pLogger.logError(Constants.INAPPROPRIATE_FUNCTION_ARG_COUNT,
- functionName, new Integer(params.length),
- new Integer(argumentList.size()));
-
- // now, walk through each parameter, evaluating and casting its argument
- Object[] arguments = new Object[argumentList.size()];
- for (int i = 0; i < params.length; i++) {
- // evaluate
- arguments[i] = ((Expression) argumentList.get(i)).evaluate(pResolver,
- functions,
- pLogger);
- // coerce
- arguments[i] = Coercions.coerce(arguments[i], params[i], pLogger);
- }
-
- // finally, invoke the target method, which we know to be static
- try {
- return (target.invoke(null, arguments));
- } catch (InvocationTargetException ex) {
- pLogger.logError(Constants.FUNCTION_INVOCATION_ERROR,
- ex.getTargetException(),
- functionName);
- return null;
- } catch (Exception ex) {
- pLogger.logError(Constants.FUNCTION_INVOCATION_ERROR, ex, functionName);
- return null;
- }
- }
-
- //-------------------------------------
- }