Java tutorial
/** * This file Copyright (c) 2003-2012 Magnolia International * Ltd. (http://www.magnolia-cms.com). All rights reserved. * * * This file is dual-licensed under both the Magnolia * Network Agreement and the GNU General Public License. * You may elect to use one or the other of these licenses. * * This file is distributed in the hope that it will be * useful, but AS-IS and WITHOUT ANY WARRANTY; without even the * implied warranty of MERCHANTABILITY or FITNESS FOR A * PARTICULAR PURPOSE, TITLE, or NONINFRINGEMENT. * Redistribution, except as permitted by whichever of the GPL * or MNA you select, is prohibited. * * 1. For the GPL license (GPL), you can redistribute and/or * modify this file under the terms of the GNU General * Public License, Version 3, as published by the Free Software * Foundation. You should have received a copy of the GNU * General Public License, Version 3 along with this program; * if not, write to the Free Software Foundation, Inc., 51 * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * 2. For the Magnolia Network Agreement (MNA), this file * and the accompanying materials are made available under the * terms of the MNA which accompanies this distribution, and * is available at http://www.magnolia-cms.com/mna.html * * Any modifications to this file must keep this entire header * intact. * */ package info.magnolia.module.files; import info.magnolia.cms.util.ClasspathResourcesUtil; import org.apache.commons.io.IOUtils; import java.io.File; import java.io.FileOutputStream; import java.io.IOException; import java.io.InputStream; import java.io.OutputStream; /** * A simple FileExtractorOperation which just extracts a resource from the class path * to the filesystem. * * @author gjoseph * @version $Revision: $ ($Author: $) */ public class BasicFileExtractorOperation implements FileExtractorOperation { protected final String resourcePath; protected final String absoluteTargetPath; BasicFileExtractorOperation(String resourcePath, String absoluteTargetPath) { this.resourcePath = resourcePath; this.absoluteTargetPath = absoluteTargetPath; } @Override public void extract() throws IOException { final InputStream resourceStream = checkInput(); final File checkedTargetFile = checkOutput(); if (checkedTargetFile != null) { final OutputStream out = openOutput(checkedTargetFile); copyAndClose(resourceStream, out); } } protected InputStream checkInput() throws IOException { final InputStream resourceStream = ClasspathResourcesUtil.getStream(resourcePath, false); if (resourceStream == null) { throw new IOException("Can't open " + resourcePath); } return resourceStream; } /** * @return a java.io.File corresponding to the absoluteTargetPath if the path is validated, * or null if the file should not be extracted. TODO ugly. */ protected File checkOutput() throws IOException { final File targetFile = new File(absoluteTargetPath); final File parent = targetFile.getParentFile(); if (!parent.exists() && !parent.mkdirs()) { throw new IOException("Can't create directories for " + targetFile.getAbsolutePath()); } else if (!parent.canWrite()) { throw new IOException("Can't write to " + targetFile.getAbsolutePath()); } return targetFile; } protected OutputStream openOutput(File targetFile) throws IOException { return new FileOutputStream(targetFile); } protected void copyAndClose(InputStream in, OutputStream out) throws IOException { try { IOUtils.copy(in, out); } finally { IOUtils.closeQuietly(in); IOUtils.closeQuietly(out); } } }