Java tutorial
package com.synedge.enforcer; /* * Licensed to the Apache Software Foundation (ASF) under one * or more contributor license agreements. See the NOTICE file * distributed with this work for additional information * regarding copyright ownership. The ASF 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. */ import org.apache.maven.enforcer.rule.api.EnforcerRule; import org.apache.maven.enforcer.rule.api.EnforcerRuleException; import org.apache.maven.enforcer.rule.api.EnforcerRuleHelper; import org.apache.maven.plugin.logging.Log; import org.apache.maven.project.MavenProject; import org.codehaus.plexus.component.configurator.expression.ExpressionEvaluationException; import org.w3c.dom.Document; import org.w3c.dom.Node; import org.w3c.dom.NodeList; import org.xml.sax.SAXException; import javax.xml.parsers.DocumentBuilder; import javax.xml.parsers.DocumentBuilderFactory; import javax.xml.parsers.ParserConfigurationException; import javax.xml.xpath.*; import java.io.IOException; /** * @author <a href="mailto:brianf@apache.org">Brian Fox</a> * @author Paul van Assen */ public class EnforceImportRelease implements EnforcerRule { /** * Allows this rule to execute only when this project is a release. * * @parameter * @see {@link #setOnlyWhenRelease(boolean)} * @see {@link #isOnlyWhenRelease()} */ private boolean onlyWhenRelease = false; public void execute(EnforcerRuleHelper helper) throws EnforcerRuleException { Log log = helper.getLog(); log.info("Entering enforcer"); try { // get the various expressions out of the helper. MavenProject project = (MavenProject) helper.evaluate("${project}"); if (project == null) { throw new EnforcerRuleException("There is no project"); } if (onlyWhenRelease && project.getArtifact().isSnapshot()) { log.warn("Project is SNAPSHOT, not validating"); return; } if (project.getDependencyManagement() == null) { log.info("No dependency management found. All ok"); return; } if (project.getDependencyManagement().getDependencies() == null) { log.info("No dependency management dependencies found. All ok"); return; } helper.getLog().debug("Getting POM, parse and check it"); DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance(); //Using factory get an instance of document builder DocumentBuilder db = dbf.newDocumentBuilder(); //parse using builder to get DOM representation of the XML file Document doc = db.parse(project.getFile().getAbsolutePath()); XPathFactory xPathfactory = XPathFactory.newInstance(); XPath xpath = xPathfactory.newXPath(); XPathExpression expr = xpath.compile( "/*[local-name()='project']/*[local-name()='dependencyManagement']/*[local-name()='dependencies']/*[local-name()='dependency']/*[local-name()='scope' and text()='import']/../*[local-name()='version']"); NodeList nl = (NodeList) expr.evaluate(doc, XPathConstants.NODESET); for (int i = 0; i < nl.getLength(); i++) { Node version = nl.item(i); if (version.getTextContent().contains("-SNAPSHOT")) { throw new EnforcerRuleException("Found an artifact in the import scope containing SNAPSHOT!"); } } helper.getLog().debug("Checked them all"); } catch (ExpressionEvaluationException e) { throw new EnforcerRuleException("Unable to lookup an expression " + e.getLocalizedMessage(), e); } catch (ParserConfigurationException e) { throw new EnforcerRuleException("Unable to parse POM", e); } catch (SAXException e) { throw new EnforcerRuleException("Unable to parse POM", e); } catch (IOException e) { throw new EnforcerRuleException("Unable to parse POM", e); } catch (XPathExpressionException e) { throw new EnforcerRuleException("Internal error in XPath parser", e); } } /** * If your rule is cacheable, you must return a unique id when parameters or conditions * change that would cause the result to be different. Multiple cached results are stored * based on their id. * <p> * The easiest way to do this is to return a hash computed from the values of your parameters. * <p> * If your rule is not cacheable, then the result here is not important, you may return anything. */ public String getCacheId() { return ""; } /** * This tells the system if the results are cacheable at all. Keep in mind that during * forked builds and other things, a given rule may be executed more than once for the same * project. This means that even things that change from project to project may still * be cacheable in certain instances. */ public boolean isCacheable() { return false; } /** * If the rule is cacheable and the same id is found in the cache, the stored results * are passed to this method to allow double checking of the results. Most of the time * this can be done by generating unique ids, but sometimes the results of objects returned * by the helper need to be queried. You may for example, store certain objects in your rule * and then query them later. */ public boolean isResultValid(EnforcerRule arg0) { return false; } public final boolean isOnlyWhenRelease() { return onlyWhenRelease; } public final void setOnlyWhenRelease(boolean onlyWhenRelease) { this.onlyWhenRelease = onlyWhenRelease; } }