GzipListTask.java

/*******************************************************************************
 * 
 * Copyright 2011-2014 Spiffy UI Team   
 * 
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 ******************************************************************************/
package org.spiffyui.build;

import java.io.File;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Iterator;

import org.apache.tools.ant.BuildException;
import org.apache.tools.ant.Project;
import org.apache.tools.ant.Task;
import org.apache.tools.ant.types.FileList;
import org.apache.tools.ant.types.FileSet;
import org.apache.tools.ant.types.Resource;
import org.apache.tools.ant.types.ResourceCollection;
import org.apache.tools.ant.types.resources.FileResource;
import org.apache.tools.ant.types.resources.Resources;
import org.apache.tools.ant.types.resources.Restrict;
import org.apache.tools.ant.types.resources.selectors.Exists;
import org.apache.tools.ant.types.resources.selectors.Not;
import org.apache.tools.ant.types.resources.selectors.ResourceSelector;
import org.apache.tools.ant.util.FileUtils;


/**
 * This is a custom task for a list of GZIPed files from a list of
 * uncompressed files
 */
public class GzipListTask extends Task
{
    
    private static final FileUtils FILE_UTILS = FileUtils.getFileUtils();
    private static final ResourceSelector EXISTS = new Exists();
    private static final ResourceSelector NOT_EXISTS = new Not(EXISTS);
    
    /**
     * The destination directory for the compressed files
     */
    private File m_destinationDir;
    
    
    /**
     * Stores a collection of file sets and/or file lists, used to
     * select multiple files for compilation.
     */
    private ResourceCollection m_rc;
    
    
    /**
     * Adds the file set of JavaScript files to compile
     * 
     * @param set    the set of files
     */
    public void addFileset(FileSet set)
    {
        add(set);
    }

    /**
     * List of files to compile.
     * 
     * @param list   the list of files
     */
    public void addFilelist(FileList list)
    {
        add(list);
    }
    
    /**
     * Sepcify the location of the directory to output the compressed files
     * 
     * @param dir the output file directory
     */
    public void setDest(File dir)
    {
        this.m_destinationDir = dir;
    }
    
    /**
     * Add an arbitrary ResourceCollection.
     * @param c the ResourceCollection to add.
     * @since Ant 1.7
     */
    public synchronized void add(ResourceCollection c)
    {
        if (m_rc == null) {
            m_rc = c;
            return;
        }
        if (!(m_rc instanceof Resources)) {
            Resources newRc = new Resources();
            newRc.setProject(getProject());
            newRc.add(m_rc);
            m_rc = newRc;
        }
        ((Resources) m_rc).add(c);
    }
    
    private ResourceCollection getResources()
    {
        if (m_rc == null) {
            return null;
        }
        Restrict noexistRc = new Restrict();
        noexistRc.add(NOT_EXISTS);
        noexistRc.add(m_rc);
        for (Iterator<Resource> i = noexistRc.iterator(); i.hasNext();) {
            log(i.next() + " does not exist.", Project.MSG_ERR);
        }
        if (m_destinationDir != null) {
            for (Iterator<Resource> i = m_rc.iterator(); i.hasNext();) {
                Object o = i.next();
                if (o instanceof FileResource) {
                    File f = ((FileResource) o).getFile();
                    if (FILE_UTILS.fileNameEquals(f, m_destinationDir)) {
                        throw new BuildException("Input file \"" + f + "\" is the same as the output directory.");
                    }
                }
            }
        }
        Restrict result = new Restrict();
        result.add(EXISTS);
        result.add(m_rc);
        return result;
    }
    
    /**
     * Reset state to default.
     */
    public void reset()
    {
        m_rc = null;
        m_destinationDir = null;
    }
    
    /**
     * Executes this task to run the compiler.
     * 
     * @exception BuildException
     *                   if there isn't enough information to run the GWT compiler
     */
    public void execute() throws BuildException
    {
        if (m_destinationDir == null) {
            throw new BuildException("Must specify an output directory");
        }
        
        if (getResources() == null) {
            return;
        }
        
        ResourceCollection rc = getResources();
        Iterator<Resource> i = rc.iterator();
        ArrayList<File> files = new ArrayList<File>();
        
        try {
            while (i.hasNext()) {
                files.add(((FileResource) i.next()).getFile());
            }
            
            GzipListUtil.zipFileList(files, m_destinationDir);
        } catch (IOException ioe) {
            throw new BuildException("Unable to GZIP file list", ioe);
        }
    }

    
}