You are viewing a plain text version of this content. The canonical link for it is here.
Posted to dev@commons.apache.org by js...@apache.org on 2003/02/19 08:44:35 UTC
cvs commit: jakarta-commons/jelly/src/java/org/apache/commons/jelly/tags/core InvokeStaticTag.java
jstrachan 2003/02/18 23:44:35
Added: jelly/src/java/org/apache/commons/jelly/tags/core
InvokeStaticTag.java
Log:
applied patch supplied by Robert McIntosh to allow invocations of static methods
Revision Changes Path
1.1 jakarta-commons/jelly/src/java/org/apache/commons/jelly/tags/core/InvokeStaticTag.java
Index: InvokeStaticTag.java
===================================================================
/*
* $Header: /home/cvs/jakarta-commons/jelly/src/java/org/apache/commons/jelly/tags/core/InvokeStaticTag.java,v 1.1 2003/02/19 07:44:35 jstrachan Exp $
* $Revision: 1.1 $
* $Date: 2003/02/19 07:44:35 $
*
* ====================================================================
*
* The Apache Software License, Version 1.1
*
* Copyright (c) 2002 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", "Commons", 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/>.
*
* $Id: InvokeStaticTag.java,v 1.1 2003/02/19 07:44:35 jstrachan Exp $
*/
package org.apache.commons.jelly.tags.core;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.util.ArrayList;
import java.util.List;
import org.apache.commons.jelly.JellyTagException;
import org.apache.commons.jelly.MissingAttributeException;
import org.apache.commons.jelly.TagSupport;
import org.apache.commons.jelly.XMLOutput;
/**
* <p>
* A Tag which can invoke a static method on a class, without an
* instance of the class being needed.
* </p>
* <p>
* Like the {@link InvokeTag}, this tag can take a set of
* arguments using the {@link ArgTag}.
* </p>
* <p>
* The following attributes are required:<br />
* <ul>
* <li>var - The variable to assign the return of the method call to</li>
* <li>method - The name of the static method to invoke</li>
* <li>className - The name of the class containing the static method</li>
* </ul>
* </p>
*
* @author <a href="mailto:robert@bull-enterprises.com>Robert McIntosh</a>
* @version $Revision: 1.1 $
*/
public class InvokeStaticTag extends TagSupport implements ArgTagParent {
/** the variable exported */
private String var;
/** the method to invoke */
private String methodName;
/** the object to invoke the method on */
private String className;
private List paramTypes = new ArrayList();
private List paramValues = new ArrayList();
public InvokeStaticTag() {
}
/**
* Sets the name of the variable exported by this tag
*
* @param var The variable name
*/
public void setVar(String var) {
this.var = var;
}
/**
* Sets the name of the method to invoke
*
* @param method The method name
*/
public void setMethod(String methodName) {
this.methodName = methodName;
}
/**
* Sets the fully qualified class name containing the static method
*
* @param className The name of the class
*/
public void setClassName(String className) {
this.className = className;
}
/**
* Adds an argument to supply to the method
*
* @param type The Class type of the argument
* @param value The value of the argument
*/
public void addArgument(Class type, Object value) {
paramTypes.add(type);
paramValues.add(value);
}
// Tag interface
//-------------------------------------------------------------------------
public void doTag(XMLOutput output) throws JellyTagException {
try {
if ( null == methodName) {
throw new MissingAttributeException( "method" );
}
invokeBody(output);
Object[] values = paramValues.toArray();
Class[] types = (Class[])(paramTypes.toArray(new Class[paramTypes.size()]));
Method method = loadClass().getMethod( methodName, types );
Object result = method.invoke( null, values );
if(null != var) {
context.setVariable(var, result);
}
ArgTag parentArg = (ArgTag)(findAncestorWithClass(ArgTag.class));
if(null != parentArg) {
parentArg.setValue(result);
}
}
catch (ClassNotFoundException e) {
throw createLoadClassFailedException(e);
}
catch (NoSuchMethodException e) {
throw createLoadClassFailedException(e);
}
catch (IllegalAccessException e) {
throw createLoadClassFailedException(e);
}
catch (InvocationTargetException e) {
throw createLoadClassFailedException(e);
}
finally {
paramTypes.clear();
paramValues.clear();
}
}
// Tag interface
//-------------------------------------------------------------------------
/**
* Loads the class using either the class loader which loaded me or the
* current threads context class loader
*/
protected Class loadClass() throws ClassNotFoundException {
Class theClass = getClass().getClassLoader().loadClass( className );
if (theClass == null ) {
theClass = Thread.currentThread().getContextClassLoader().loadClass( className );
}
return theClass;
}
/**
* Factory method to create a new JellyTagException instance from a given
* failure exception
* @param e is the exception which occurred attempting to load the class
* @return JellyTagException
*/
protected JellyTagException createLoadClassFailedException(Exception e) {
return new JellyTagException(
"Could not load class: " + className + ". Reason: " + e, e
);
}
}
---------------------------------------------------------------------
To unsubscribe, e-mail: commons-dev-unsubscribe@jakarta.apache.org
For additional commands, e-mail: commons-dev-help@jakarta.apache.org