001    /*
002     $Id: RootLoaderRef.java,v 1.2 2005/09/21 16:55:58 glaforge Exp $
003    
004     Copyright 2003 (C) James Strachan and Bob Mcwhirter. All Rights Reserved.
005    
006     Redistribution and use of this software and associated documentation
007     ("Software"), with or without modification, are permitted provided
008     that the following conditions are met:
009    
010     1. Redistributions of source code must retain copyright
011        statements and notices.  Redistributions must also contain a
012        copy of this document.
013    
014     2. Redistributions in binary form must reproduce the
015        above copyright notice, this list of conditions and the
016        following disclaimer in the documentation and/or other
017        materials provided with the distribution.
018    
019     3. The name "groovy" must not be used to endorse or promote
020        products derived from this Software without prior written
021        permission of The Codehaus.  For written permission,
022        please contact info@codehaus.org.
023    
024     4. Products derived from this Software may not be called "groovy"
025        nor may "groovy" appear in their names without prior written
026        permission of The Codehaus. "groovy" is a registered
027        trademark of The Codehaus.
028    
029     5. Due credit should be given to The Codehaus -
030        http://groovy.codehaus.org/
031    
032     THIS SOFTWARE IS PROVIDED BY THE CODEHAUS AND CONTRIBUTORS
033     ``AS IS'' AND ANY EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT
034     NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
035     FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL
036     THE CODEHAUS OR ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
037     INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
038     (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
039     SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
040     HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
041     STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
042     ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
043     OF THE POSSIBILITY OF SUCH DAMAGE.
044    
045     */
046     
047    package org.codehaus.groovy.ant;
048    
049    import org.apache.tools.ant.AntClassLoader;
050    import org.apache.tools.ant.BuildException;
051    import org.apache.tools.ant.Project;
052    import org.apache.tools.ant.taskdefs.MatchingTask;
053    import org.apache.tools.ant.types.Path;
054    import org.apache.tools.ant.types.Reference;
055    import org.codehaus.groovy.tools.LoaderConfiguration;
056    import org.codehaus.groovy.tools.RootLoader;
057    
058     
059    /**
060     * Sets the RootLoader as reference.
061     * Reexecution of this task will set a new instance of RootLoader for
062     * the reference. 
063     *
064     * arguments:
065     * <ul>
066     * <li>ref</li>
067     * <li>classpath</li>
068     * </ul>
069     * 
070     * all arguments are requiered. 
071     *
072     * As ant requieres an AntClassLoader as reference, this will create a RootLoader
073     * and set an AntClassLoader as child and stored in the reference. The AntClassLoader
074     * instance will not have a classpath nor will it have access to the classpath somehow,
075     * all loading is done by the RootLoader parent. To avoid problems with loading classes 
076     * multiple times and using them at the same time, this task will filter out the ant jars
077     * and the commons-logging jars. This only works if the ant jars are starting with "ant-" and
078     * the logging jar starts with "commons-logging-".
079     * 
080     * This was needed because if ant wants to access a task argument that uses for example a Path
081     * it look for a matching method which includes a matching class. But two classes of the same name
082     * with different classloaders are different, so ant would not be able to find the method.
083     *
084     * @see org.codehaus.groovy.tools.RootLoader
085     * @author Jochen Theodorou
086     * @version $Revision: 1.2 $ 
087     */
088    public class RootLoaderRef extends MatchingTask {
089        private String name;
090        private Path taskClasspath;
091        
092        /**
093         * sets the name of the reference which should store the Loader
094         */
095        public void setRef(String n){
096            name = n;
097        }
098        
099        public void execute() throws BuildException {
100            if (taskClasspath==null || taskClasspath.size()==0) {
101                throw new BuildException("no classpath given");
102            }
103            Project project = getProject();
104            AntClassLoader loader = new AntClassLoader(makeRoot(),true);
105            project.addReference(name,loader);
106        }
107        
108        private RootLoader makeRoot() {
109            String[] list = taskClasspath.list();
110            LoaderConfiguration lc = new LoaderConfiguration();
111            for (int i=0; i<list.length; i++) {
112                if (list[i].matches(".*ant-[^/]*jar$")) {
113                    continue;
114                }
115                if (list[i].matches(".*commons-logging-[^/]*jar$")) {
116                    continue;
117                }
118                lc.addFile(list[i]);
119            }
120            return new RootLoader(lc);
121        }
122        
123        /**
124         * Set the classpath to be used for this compilation.
125         *
126         * @param classpath an Ant Path object containing the compilation classpath.
127         */
128        public void setClasspath(Path classpath) {
129            if (taskClasspath == null) {
130                taskClasspath = classpath;
131            }
132            else {
133                taskClasspath.append(classpath);
134            }
135        }
136        
137        /**
138         * Adds a reference to a classpath defined elsewhere.
139         * @param r a reference to a classpath
140         */
141        public void setClasspathRef(Reference r) {
142            createClasspath().setRefid(r);
143        }
144        
145        /**
146         * Adds a path to the classpath.
147         * @return a class path to be configured
148         */
149        public Path createClasspath() {
150            if (taskClasspath == null) {
151                taskClasspath = new Path(getProject());
152            }
153            return taskClasspath.createPath();
154        }
155    }