com.phoenixnap.oss.ramlapisync.plugin.ClassLoaderUtils.java Source code

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Here is the source code for com.phoenixnap.oss.ramlapisync.plugin.ClassLoaderUtils.java

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/*
 * Copyright 2002-2016 the original author or authors.
 * 
 * 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 com.phoenixnap.oss.ramlapisync.plugin;

import java.io.File;
import java.net.MalformedURLException;
import java.net.URL;
import java.net.URLClassLoader;
import java.util.Collection;
import java.util.List;
import java.util.Set;

import org.apache.commons.io.FileUtils;
import org.apache.commons.io.filefilter.DirectoryFileFilter;
import org.apache.commons.io.filefilter.SuffixFileFilter;
import org.apache.commons.io.filefilter.TrueFileFilter;
import org.apache.maven.artifact.Artifact;
import org.apache.maven.plugin.MojoExecutionException;
import org.apache.maven.project.MavenProject;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import com.google.common.collect.Lists;

/**
 * Class containing utility methods for loading different sets of classes during Plugin runtime
 * 
 * @author Kurt Paris
 * @since 0.0.1
 *
 */
public final class ClassLoaderUtils {

    protected static final Logger logger = LoggerFactory.getLogger(ClassLoaderUtils.class);

    private static ClassLoader originalClassLoader;

    private ClassLoaderUtils() {

    }

    public static void addLocationsToClassLoader(MavenProject mavenProject) throws MojoExecutionException {

        List<URL> urls = Lists.newArrayList();
        try {
            urls.add(new File(mavenProject.getBuild().getOutputDirectory()).toURI().toURL());

            // Getting all artifacts locations
            Set<Artifact> artifacts = mavenProject.getArtifacts();

            for (Artifact artifact : artifacts) {
                urls.add(artifact.getFile().toURI().toURL());
            }

        } catch (MalformedURLException e) {
            // DO NOTHING
        }

        /*
         * this was failing when executing goal on a maven project if (originalClassLoader != null) { throw new
         * MojoExecutionException( "Context setting of the current thread ClassLoader is allowed only once."); }
         */

        // Store ClassLoader before applying modifications.
        originalClassLoader = Thread.currentThread().getContextClassLoader();

        Thread.currentThread()
                .setContextClassLoader(new URLClassLoader(urls.toArray(new URL[urls.size()]), originalClassLoader));

    }

    public static List<String> loadPackages(MavenProject mavenProject) throws MojoExecutionException {

        List<String> packages = Lists.newArrayList();

        logger.info("Loading packages in " + mavenProject.getBuild().getSourceDirectory() + "...");
        File rootDir = new File(mavenProject.getBuild().getSourceDirectory() + "//");
        Collection<File> files = FileUtils.listFilesAndDirs(rootDir, DirectoryFileFilter.DIRECTORY,
                TrueFileFilter.TRUE);
        for (File file : files) {
            String pack = file.toString().replace(rootDir.toString(), "").replace(File.separator, ".");
            if (pack.startsWith(".")) {
                pack = pack.substring(1, pack.length());
            }
            if (!pack.isEmpty()) {
                packages.add(pack);
            }
        }

        return packages;
    }

    public static List<String> loadClasses(MavenProject mavenProject) throws MojoExecutionException {

        List<String> classes = Lists.newArrayList();

        File rootDir = new File(mavenProject.getBuild().getSourceDirectory());
        Collection<File> files = FileUtils.listFiles(rootDir, new SuffixFileFilter(".java"), TrueFileFilter.TRUE);
        for (File file : files) {
            String clazz = file.getName().replace(".java", "");
            if (!clazz.isEmpty()) {
                classes.add(clazz);
            }
        }
        return classes;
    }

    public static void restoreOriginalClassLoader() throws MojoExecutionException {

        if (originalClassLoader == null) {
            throw new MojoExecutionException("Original ClassLoader not available.");
        }
        Thread.currentThread().setContextClassLoader(originalClassLoader);
    }

}