Java tutorial
/** * Licensed to the Sakai Foundation (SF) under one * or more contributor license agreements. See the NOTICE file * distributed with this work for additional information * regarding copyright ownership. The SF licenses this file * to you 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.sakaiproject.nakamura.maven; import org.apache.maven.artifact.Artifact; import org.apache.maven.artifact.factory.ArtifactFactory; import org.apache.maven.artifact.repository.ArtifactRepository; import org.apache.maven.artifact.resolver.ArtifactNotFoundException; import org.apache.maven.artifact.resolver.ArtifactResolutionException; import org.apache.maven.artifact.resolver.ArtifactResolver; import org.apache.maven.artifact.versioning.InvalidVersionSpecificationException; import org.apache.maven.artifact.versioning.VersionRange; import org.apache.maven.model.Dependency; import org.apache.maven.plugin.AbstractMojo; import org.apache.maven.plugin.MojoExecutionException; import org.apache.maven.project.MavenProject; import org.codehaus.plexus.util.DirectoryScanner; import org.codehaus.plexus.util.StringUtils; import org.drools.KnowledgeBase; import org.drools.RuleBase; import org.drools.RuleBaseConfiguration; import org.drools.RuleBaseFactory; import org.drools.builder.KnowledgeBuilderError; import org.drools.compiler.PackageBuilder; import org.drools.compiler.PackageBuilderConfiguration; import org.drools.compiler.PackageBuilderErrors; import org.drools.impl.KnowledgeBaseImpl; import org.drools.rule.Package; import org.drools.runtime.StatelessKnowledgeSession; import org.drools.util.DroolsStreamUtils; import java.io.File; import java.io.FileInputStream; import java.io.FileOutputStream; import java.io.FileReader; import java.io.Reader; import java.net.URL; import java.net.URLClassLoader; import java.util.ArrayList; import java.util.Arrays; import java.util.List; /** * @goal compile-rules */ public class DroolsCompilerMojo extends AbstractMojo { /** * @parameter default-value={"**\/*"} */ protected String[] includes; /** * @parameter default-value={} */ protected String[] excludes; /** * @parameter default-value="${basedir}/src/main/rules" */ protected File rulesdir; /** * The output directory for bundles. * * @parameter default-value="${project.build.directory}/classes" */ protected File outputDirectory; /** * The output directory for bundles. * * @parameter default-value= * "SLING-INF/content/var/rules/${project.groupId}/${project.artifactId}/${project.version}/${project.artifactId}-${project.version}.pkg" */ protected String packageOutputName; /** * The Maven project. * * @parameter expression="${project}" * @required * @readonly */ protected MavenProject project; /** * Used to look up Artifacts in the remote repository. * * @component */ protected ArtifactFactory factory; /** * Used to look up Artifacts in the remote repository. * * @component */ protected ArtifactResolver resolver; /** * Location of the local repository. * * @parameter expression="${localRepository}" * @readonly * @required */ protected ArtifactRepository local; /** * List of Remote Repositories used by the resolver. * * @parameter expression="${project.remoteArtifactRepositories}" * @readonly * @required */ protected List<?> remoteRepos; public void execute() throws MojoExecutionException { // find all the rules items and load them into a package try { // Need to load the build classpath @SuppressWarnings("unchecked") List<Dependency> dependencies = project.getDependencies(); List<URL> url = new ArrayList<URL>(); url.add(outputDirectory.toURI().toURL()); for (Dependency d : dependencies) { String scope = d.getScope(); if (!Artifact.SCOPE_TEST.equals(scope)) { Artifact artifact = getArtifact(d.getGroupId(), d.getArtifactId(), d.getVersion(), d.getType(), d.getClassifier()); url.add(artifact.getFile().toURI().toURL()); } } URL[] classpath = url.toArray(new URL[url.size()]); URLClassLoader uc = new URLClassLoader(classpath, this.getClass().getClassLoader()) { @Override public Class<?> loadClass(String name) throws ClassNotFoundException { getLog().debug("Loading Class for compile [" + name + "]"); Class<?> c = super.loadClass(name); getLog().debug("Loading Class for compile [" + name + "] found [" + c + "]"); return c; } @Override protected Class<?> findClass(String name) throws ClassNotFoundException { getLog().debug("Finding Class for compile [" + name + "]"); Class<?> c = super.findClass(name); getLog().debug("Finding Class for compile [" + name + "] found [" + c + "]"); return c; } }; URLClassLoader uc2 = new URLClassLoader(classpath, this.getClass().getClassLoader()) { @Override public Class<?> loadClass(String name) throws ClassNotFoundException { getLog().debug("Loading Class for runtime [" + name + "]"); Class<?> c = super.loadClass(name); getLog().debug("Loading Class for runtime [" + name + "] found [" + c + "]"); return c; } @Override protected Class<?> findClass(String name) throws ClassNotFoundException { getLog().debug("Finding Class for runtime [" + name + "]"); Class<?> c = super.findClass(name); getLog().debug("Finding Class for runtime [" + name + "] found [" + c + "]"); return c; } }; getLog().info("Package Class loader is using classpath " + Arrays.toString(uc.getURLs())); listClassloader(" ", uc); PackageBuilderConfiguration packageBuilderConfiguration = new PackageBuilderConfiguration(uc); PackageBuilder pb = new PackageBuilder(packageBuilderConfiguration); DirectoryScanner ds = new DirectoryScanner(); ds.setIncludes(includes); ds.setExcludes(excludes); ds.setBasedir(rulesdir); ds.setCaseSensitive(true); ds.scan(); String[] files = ds.getIncludedFiles(); for (String file : files) { File f = new File(rulesdir, file); Reader reader = new FileReader(f); try { if (file.endsWith(".drl")) { getLog().info("Adding Rules " + f); pb.addPackageFromDrl(reader); } else if (file.endsWith(".xml")) { getLog().info("Adding Package definition " + f); pb.addPackageFromXml(reader); } else if (file.endsWith(".rf")) { getLog().info("Adding Rule Flow " + f); pb.addRuleFlow(reader); } else { getLog().info("Ignored Resource " + f); } } finally { reader.close(); } } pb.compileAll(); PackageBuilderErrors errors = pb.getErrors(); if (errors.size() > 0) { for (KnowledgeBuilderError kberr : errors) { getLog().error(kberr.toString()); } throw new MojoExecutionException("Package is not valid"); } org.drools.rule.Package p = pb.getPackage(); if (!p.isValid()) { getLog().error("Package is not valid "); throw new MojoExecutionException("Package is not valid"); } File outputFile = getOutputFile(); getLog().info("Saving compiled package to " + outputFile.getPath()); outputFile.getParentFile().mkdirs(); FileOutputStream fout = new FileOutputStream(outputFile); DroolsStreamUtils.streamOut(fout, p); fout.close(); getLog().info("Testing Compiled package " + outputFile.getPath()); File inputFile = getOutputFile(); FileInputStream fin = new FileInputStream(inputFile); RuleBaseConfiguration config = new RuleBaseConfiguration(uc2); RuleBase ruleBase = RuleBaseFactory.newRuleBase(config); Object o = DroolsStreamUtils.streamIn(fin, uc); ruleBase.addPackage((Package) o); KnowledgeBase kb = new KnowledgeBaseImpl(ruleBase); @SuppressWarnings("unused") StatelessKnowledgeSession session = kb.newStatelessKnowledgeSession(); getLog().info("Testing passed "); } catch (Exception e) { getLog().error(e); throw new MojoExecutionException(e.getMessage()); } } /** * Get a resolved Artifact from the coordinates provided * * @return the artifact, which has been resolved. * @throws MojoExecutionException */ protected Artifact getArtifact(String groupId, String artifactId, String version, String type, String classifier) throws MojoExecutionException { Artifact artifact; VersionRange vr; try { vr = VersionRange.createFromVersionSpec(version); } catch (InvalidVersionSpecificationException e) { vr = VersionRange.createFromVersion(version); } if (StringUtils.isEmpty(classifier)) { artifact = factory.createDependencyArtifact(groupId, artifactId, vr, type, null, Artifact.SCOPE_COMPILE); } else { artifact = factory.createDependencyArtifact(groupId, artifactId, vr, type, classifier, Artifact.SCOPE_COMPILE); } try { resolver.resolve(artifact, remoteRepos, local); } catch (ArtifactResolutionException e) { throw new MojoExecutionException("Unable to resolve artifact.", e); } catch (ArtifactNotFoundException e) { throw new MojoExecutionException("Unable to find artifact.", e); } return artifact; } private void listClassloader(String indent, ClassLoader uc) { if (uc != null) { if (uc instanceof URLClassLoader) { URLClassLoader urlC = (URLClassLoader) uc; getLog().debug(indent + "Classloader : " + uc + " " + Arrays.toString(urlC.getURLs())); } else { getLog().debug(indent + "Classloader : " + uc); } listClassloader(indent + " ", uc.getParent()); } } private File getOutputFile() { return new File(outputDirectory, packageOutputName); } }