com.github.k0zka.contentcompress.ContentGzipMojo.java Source code

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Here is the source code for com.github.k0zka.contentcompress.ContentGzipMojo.java

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package com.github.k0zka.contentcompress;

/*
 * Copyright 2001-2005 The Apache Software Foundation.
 *
 * 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.
 */

import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import java.util.zip.GZIPOutputStream;

import org.apache.commons.io.FileUtils;
import org.apache.commons.io.IOUtils;
import org.apache.commons.lang.ObjectUtils;
import org.apache.maven.plugin.AbstractMojo;
import org.apache.maven.plugin.MojoExecutionException;

/**
 * This goal creates a gzip-ed file from each file in the webapp that matches
 * the filename pattern.
 * 
 * @goal process
 * 
 * @phase prepare-package
 */
public class ContentGzipMojo extends AbstractMojo {
    /**
     * Location of the webapp.
     * 
     * @parameter expression="src/main/webapp"
     * @required
     */
    private File webappDirectory;

    /**
     * Location of the file.
     * 
     * @parameter 
     *            expression="${project.build.directory}/${project.build.finalName}"
     * @required
     */
    private File outputDirectory;
    /**
     * File name suffixes to handle with the gzip compression.
     * 
     * @parameter
     */
    private List<String> extensions = getDefaultExtensions();

    /**
     * The minimal size for files to compress.
     * 
     * @parameter
     */
    private long minSize = 0;

    public void execute() throws MojoExecutionException {
        getLog().info("Compressing static resources with gzip...");
        try {
            if (!ObjectUtils.equals(webappDirectory, outputDirectory)) {
                FileUtils.copyDirectory(webappDirectory, outputDirectory, new DotNotFilter());
            }
            seekAndGzip(outputDirectory);
        } catch (IOException e) {
            throw new MojoExecutionException("IO exception when gzipping files", e);
        }
    }

    List<String> getDefaultExtensions() {
        final ArrayList<String> ret = new ArrayList<String>();
        ret.add(".css");
        ret.add(".txt");
        ret.add(".html");
        ret.add(".htm");
        ret.add(".js");
        ret.add(".xml");
        ret.add(".xls");
        ret.add(".ico");
        ret.add(".svg");
        ret.add(".pdf");
        ret.add(".doc");
        return ret;
    }

    void seekAndGzip(final File directory) throws IOException {
        final String[] fileNames = directory.list(new FilesToGzipFilter(minSize, extensions));
        if (fileNames == null) {
            getLog().error("Directory does not exist: " + directory.getAbsolutePath());
            return;
        }
        for (final String fileName : fileNames) {
            compress(directory, fileName);
        }
        final String[] subDirs = directory.list(new SubdirsFilter());
        for (final String subDir : subDirs) {
            seekAndGzip(new File(directory, subDir));
        }
    }

    void compress(final File directory, final String fileName) throws IOException {
        final File sourceFile = new File(directory, fileName);
        final File gzippedFile = new File(directory, fileName.concat(".gz"));
        if (gzippedFile.exists() && gzippedFile.lastModified() > sourceFile.lastModified()) {
            getLog().info("Skipped file " + sourceFile.getName() + " .gz is up to date");
            return;
        }
        final FileInputStream inputStream = new FileInputStream(sourceFile);
        final FileOutputStream fileStream = new FileOutputStream(gzippedFile);
        final GZIPOutputStream gzipStream = new GZIPOutputStream(fileStream);
        IOUtils.copy(inputStream, gzipStream);
        IOUtils.closeQuietly(inputStream);
        IOUtils.closeQuietly(gzipStream);
        IOUtils.closeQuietly(fileStream);
        final long sourceLength = sourceFile.length();
        final long gzipedLength = gzippedFile.length();
        if (sourceLength > gzipedLength) {
            getLog().info("Compressed file " + sourceFile.getName() + ". " + sourceLength + " -> " + gzipedLength);
        } else {
            getLog().info("Compressed file " + sourceFile.getName() + ". " + sourceLength + " -> " + gzipedLength
                    + " removing, gzipped version is bigger");
            gzippedFile.delete();
        }
    }

}