src/main/java/freemarker/ext/ant/JythonAntTask.java

/*
 * Copyright (c) 2003 The Visigoth Software Society. 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 acknowledgement:
 *       "This product includes software developed by the
 *        Visigoth Software Society (http://www.visigoths.org/)."
 *    Alternately, this acknowledgement may appear in the software itself,
 *    if and wherever such third-party acknowledgements normally appear.
 *
 * 4. Neither the name "FreeMarker", "Visigoth", nor any of the names of the 
 *    project contributors may be used to endorse or promote products derived
 *    from this software without prior written permission. For written
 *    permission, please contact visigoths@visigoths.org.
 *
 * 5. Products derived from this software may not be called "FreeMarker" or "Visigoth"
 *    nor may "FreeMarker" or "Visigoth" appear in their names
 *    without prior written permission of the Visigoth Software Society.
 *
 * 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 VISIGOTH SOFTWARE SOCIETY 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 Visigoth Software Society. For more
 * information on the Visigoth Software Society, please see
 * http://www.visigoths.org/
 */

package freemarker.ext.ant;

import java.io.File;
import java.util.Map;

import org.apache.tools.ant.BuildException;
import org.apache.tools.ant.ProjectHelper;
import org.apache.tools.ant.Task;

import freemarker.template.utility.ClassUtil;

/**
 * Used internally, public for technical reasons only.
 * 
 * <p>This is an Ant sub-task of the {@link FreemarkerXmlTask} task.
 * 
 * <p><b>Warning! It must not be statically linked with Jython classes</b>,
 * so users can use the XML ant task even if Jython is not installed. 
 */
public class JythonAntTask extends Task {
    
    private File scriptFile;
    private String script = "";
    private UnlinkedJythonOperations jythonOps;
    
    public void setFile(File scriptFile) throws BuildException {
        ensureJythonOpsExists();
        this.scriptFile = scriptFile;
    }
    
    public void addText(String text) {
        script += text;
    }
    
    public void execute(Map vars) throws BuildException {
        if (scriptFile != null) {
            ensureJythonOpsExists();
            jythonOps.execute(scriptFile, vars);
        } 
        if (script.trim().length() >0) {
            ensureJythonOpsExists();
            String finalScript = ProjectHelper.replaceProperties(
                    project, script, project.getProperties());
            jythonOps.execute(finalScript, vars);
        }
    }

    private void ensureJythonOpsExists() {
        if (jythonOps == null) {
            Class clazz;
            try {
                clazz = ClassUtil.forName(
                        "freemarker.ext.ant.UnlinkedJythonOperationsImpl");
            } catch (ClassNotFoundException e) {
                throw new RuntimeException(
                        "A ClassNotFoundException has been thrown when trying "
                        + "to get the "
                        + "freemarker.ext.ant.UnlinkedJythonOperationsImpl class. "
                        + "The error message was: " + e.getMessage());
            }
            try {
                jythonOps
                        = (UnlinkedJythonOperations) clazz.newInstance();
            } catch (Exception e) {
                throw new RuntimeException(
                        "An exception has been thrown when trying "
                        + "to create a freemarker.ext.ant.JythonAntTask "
                        + "object. The exception was: " + e);
            }
        }
    }
    
}