Java tutorial
package org.eclipse.che.maven.server; /* * 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.execution.MavenExecutionRequest; import org.apache.maven.model.Model; import org.apache.maven.model.io.xpp3.MavenXpp3Writer; import org.apache.maven.plugin.MojoExecutionException; import org.apache.maven.project.MavenProject; import org.apache.maven.project.ProjectBuilder; import org.apache.maven.project.ProjectBuildingException; import org.apache.maven.project.ProjectBuildingResult; import org.codehaus.plexus.util.xml.PrettyPrintXMLWriter; import org.codehaus.plexus.util.xml.XMLWriter; import org.codehaus.plexus.util.xml.XmlWriterUtil; import org.jdom.Document; import org.jdom.Element; import org.jdom.JDOMException; import org.jdom.Namespace; import org.jdom.filter.ElementFilter; import org.jdom.input.SAXBuilder; import org.jdom.output.Format; import org.jdom.output.XMLOutputter; import java.io.File; import java.io.IOException; import java.io.StringReader; import java.io.StringWriter; import java.text.DateFormat; import java.text.SimpleDateFormat; import java.util.ArrayList; import java.util.Collections; import java.util.Date; import java.util.Iterator; import java.util.LinkedHashSet; import java.util.List; import java.util.Properties; import java.util.Set; class EffectivePomWriter { private static final String POM_XSD_URL = "http://maven.apache.org/maven-v4_0_0.xsd"; private static final String SETTINGS_XSD_URL = "http://maven.apache.org/xsd/settings-1.0.0.xsd"; private EffectivePomWriter() { } public static String getEffectivePom(MavenServerImpl server, final File pom, List<String> activeProfiles, List<String> inactiveProfiles) { StringWriter stringWriter = new StringWriter(); try { MavenExecutionRequest request = server.newMavenRequest(pom, activeProfiles, inactiveProfiles, Collections.emptyList()); server.runMavenRequest(request, () -> { try { ProjectBuilder builder = server.getMavenComponent(ProjectBuilder.class); ProjectBuildingResult projectBuildingResult = builder.build(new File(pom.getPath()), request.getProjectBuildingRequest()); MavenProject project = projectBuildingResult.getProject(); XMLWriter writer = new PrettyPrintXMLWriter(stringWriter, " "); writeHeader(writer); writeEffectivePom(project, writer); } catch (ProjectBuildingException | MojoExecutionException e) { e.printStackTrace(); throw new RuntimeException(e); } }); } catch (Exception e) { return null; } return stringWriter.toString(); } /** * method from org.apache.maven.plugins.help.EffectivePomMojo * Method for writing the effective pom informations of the current build. * * @param project the project of the current build, not null. * @param writer the XML writer , not null, not null. * @throws MojoExecutionException if any */ private static void writeEffectivePom(MavenProject project, XMLWriter writer) throws MojoExecutionException { Model pom = project.getModel(); cleanModel(pom); String effectivePom; StringWriter sWriter = new StringWriter(); MavenXpp3Writer pomWriter = new MavenXpp3Writer(); try { pomWriter.write(sWriter, pom); } catch (IOException e) { throw new MojoExecutionException("Cannot serialize POM to XML.", e); } effectivePom = addMavenNamespace(sWriter.toString(), true); writeComment(writer, "Effective POM for project \'" + project.getId() + "\'"); writer.writeMarkup(effectivePom); } /** * method from org.apache.maven.plugins.help.EffectivePomMojo * Apply some logic to clean the model before writing it. * * @param pom not null */ private static void cleanModel(Model pom) { Properties properties = new SortedProperties(); properties.putAll(pom.getProperties()); pom.setProperties(properties); } /** * method from org.apache.maven.plugins.help.AbstractEffectiveMojo * Write comments in the Effective POM/settings header. * * @param writer not null */ protected static void writeHeader(XMLWriter writer) { XmlWriterUtil.writeCommentLineBreak(writer); XmlWriterUtil.writeComment(writer, " "); // Use ISO8601-format for date and time DateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd'T'hh:mm:ss"); XmlWriterUtil.writeComment(writer, "Generated by Maven Help Plugin on " + dateFormat.format(new Date(System.currentTimeMillis()))); XmlWriterUtil.writeComment(writer, "See: http://maven.apache.org/plugins/maven-help-plugin/"); XmlWriterUtil.writeComment(writer, " "); XmlWriterUtil.writeCommentLineBreak(writer); XmlWriterUtil.writeLineBreak(writer); } /** * method from org.apache.maven.plugins.help.AbstractEffectiveMojo * Write comments in a normalize way. * * @param writer not null * @param comment not null */ protected static void writeComment(XMLWriter writer, String comment) { XmlWriterUtil.writeCommentLineBreak(writer); XmlWriterUtil.writeComment(writer, " "); XmlWriterUtil.writeComment(writer, comment); XmlWriterUtil.writeComment(writer, " "); XmlWriterUtil.writeCommentLineBreak(writer); XmlWriterUtil.writeLineBreak(writer); } /** * method from org.apache.maven.plugins.help.AbstractEffectiveMojo * Add a Pom/Settings namespaces to the effective XML content. * * @param effectiveXml not null the effective POM or Settings * @param isPom if <code>true</code> add the Pom xsd url, otherwise add the settings xsd url. * @return the content of the root element, i.e. <project/> or <settings/> with the Maven namespace or * the original <code>effective</code> if an error occurred. * @see #POM_XSD_URL * @see #SETTINGS_XSD_URL */ protected static String addMavenNamespace(String effectiveXml, boolean isPom) { SAXBuilder builder = new SAXBuilder(); try { Document document = builder.build(new StringReader(effectiveXml)); Element rootElement = document.getRootElement(); // added namespaces Namespace pomNamespace = Namespace.getNamespace("", "http://maven.apache.org/POM/4.0.0"); rootElement.setNamespace(pomNamespace); Namespace xsiNamespace = Namespace.getNamespace("xsi", "http://www.w3.org/2001/XMLSchema-instance"); rootElement.addNamespaceDeclaration(xsiNamespace); if (rootElement.getAttribute("schemaLocation", xsiNamespace) == null) { rootElement.setAttribute("schemaLocation", "http://maven.apache.org/POM/4.0.0 " + (isPom ? POM_XSD_URL : SETTINGS_XSD_URL), xsiNamespace); } ElementFilter elementFilter = new ElementFilter(Namespace.getNamespace("")); for (Iterator<?> i = rootElement.getDescendants(elementFilter); i.hasNext();) { Element e = (Element) i.next(); e.setNamespace(pomNamespace); } StringWriter w = new StringWriter(); Format format = Format.getPrettyFormat(); XMLOutputter out = new XMLOutputter(format); out.output(document.getRootElement(), w); return w.toString(); } catch (JDOMException e) { return effectiveXml; } catch (IOException e) { return effectiveXml; } } /** * Class from org.apache.maven.plugins.help.AbstractEffectiveMojo * Properties which provides a sorted keySet(). */ protected static class SortedProperties extends Properties { /** serialVersionUID */ static final long serialVersionUID = -8985316072702233744L; /** {@inheritDoc} */ @SuppressWarnings({ "rawtypes", "unchecked" }) public Set<Object> keySet() { Set<Object> keynames = super.keySet(); List list = new ArrayList(keynames); Collections.sort(list); return new LinkedHashSet<Object>(list); } } }