Java tutorial
package org.apache.maven.artifact.repository.metadata; /* * 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.artifact.Artifact; import org.apache.maven.artifact.metadata.ArtifactMetadata; import org.apache.maven.artifact.repository.ArtifactRepository; import org.apache.maven.artifact.repository.ArtifactRepositoryPolicy; import org.apache.maven.artifact.repository.metadata.io.xpp3.MetadataXpp3Reader; import org.apache.maven.artifact.repository.metadata.io.xpp3.MetadataXpp3Writer; import org.codehaus.plexus.util.ReaderFactory; import org.codehaus.plexus.util.WriterFactory; import org.codehaus.plexus.util.xml.pull.XmlPullParserException; import java.io.File; import java.io.IOException; import java.io.Reader; import java.io.Writer; /** * Shared methods of the repository metadata handling. * * @author <a href="mailto:brett@apache.org">Brett Porter</a> */ public abstract class AbstractRepositoryMetadata implements RepositoryMetadata { private Metadata metadata; protected AbstractRepositoryMetadata(Metadata metadata) { this.metadata = metadata; } public String getRemoteFilename() { return "maven-metadata.xml"; } public String getLocalFilename(ArtifactRepository repository) { return "maven-metadata-" + repository.getKey() + ".xml"; } public void storeInLocalRepository(ArtifactRepository localRepository, ArtifactRepository remoteRepository) throws RepositoryMetadataStoreException { try { updateRepositoryMetadata(localRepository, remoteRepository); } catch (IOException | XmlPullParserException e) { throw new RepositoryMetadataStoreException("Error updating group repository metadata", e); } } protected void updateRepositoryMetadata(ArtifactRepository localRepository, ArtifactRepository remoteRepository) throws IOException, XmlPullParserException { MetadataXpp3Reader mappingReader = new MetadataXpp3Reader(); Metadata metadata = null; File metadataFile = new File(localRepository.getBasedir(), localRepository.pathOfLocalRepositoryMetadata(this, remoteRepository)); if (metadataFile.length() == 0) { if (!metadataFile.delete()) { // sleep for 10ms just in case this is windows holding a file lock try { Thread.sleep(10); } catch (InterruptedException e) { // ignore } metadataFile.delete(); // if this fails, forget about it, we'll try to overwrite it anyway so no need // to delete on exit } } else if (metadataFile.exists()) { try (Reader reader = ReaderFactory.newXmlReader(metadataFile)) { metadata = mappingReader.read(reader, false); } } boolean changed; // If file could not be found or was not valid, start from scratch if (metadata == null) { metadata = this.metadata; changed = true; } else { changed = metadata.merge(this.metadata); } // beware meta-versions! String version = metadata.getVersion(); if (version != null && (Artifact.LATEST_VERSION.equals(version) || Artifact.RELEASE_VERSION.equals(version))) { // meta-versions are not valid <version/> values...don't write them. metadata.setVersion(null); } if (changed || !metadataFile.exists()) { metadataFile.getParentFile().mkdirs(); try (Writer writer = WriterFactory.newXmlWriter(metadataFile)) { MetadataXpp3Writer mappingWriter = new MetadataXpp3Writer(); mappingWriter.write(writer, metadata); } } else { metadataFile.setLastModified(System.currentTimeMillis()); } } public String toString() { return "repository metadata for: \'" + getKey() + "\'"; } protected static Metadata createMetadata(Artifact artifact, Versioning versioning) { Metadata metadata = new Metadata(); metadata.setGroupId(artifact.getGroupId()); metadata.setArtifactId(artifact.getArtifactId()); metadata.setVersion(artifact.getVersion()); metadata.setVersioning(versioning); return metadata; } protected static Versioning createVersioning(Snapshot snapshot) { Versioning versioning = new Versioning(); versioning.setSnapshot(snapshot); versioning.updateTimestamp(); return versioning; } public void setMetadata(Metadata metadata) { this.metadata = metadata; } public Metadata getMetadata() { return metadata; } public void merge(org.apache.maven.repository.legacy.metadata.ArtifactMetadata metadata) { // TODO not sure that it should assume this, maybe the calls to addMetadata should pre-merge, then artifact // replaces? AbstractRepositoryMetadata repoMetadata = (AbstractRepositoryMetadata) metadata; this.metadata.merge(repoMetadata.getMetadata()); } public void merge(ArtifactMetadata metadata) { // TODO not sure that it should assume this, maybe the calls to addMetadata should pre-merge, then artifact // replaces? AbstractRepositoryMetadata repoMetadata = (AbstractRepositoryMetadata) metadata; this.metadata.merge(repoMetadata.getMetadata()); } public String extendedToString() { StringBuilder buffer = new StringBuilder(256); buffer.append("\nRepository Metadata\n--------------------------"); buffer.append("\nGroupId: ").append(getGroupId()); buffer.append("\nArtifactId: ").append(getArtifactId()); buffer.append("\nMetadata Type: ").append(getClass().getName()); return buffer.toString(); } public int getNature() { return RELEASE; } public ArtifactRepositoryPolicy getPolicy(ArtifactRepository repository) { int nature = getNature(); if ((nature & RepositoryMetadata.RELEASE_OR_SNAPSHOT) == RepositoryMetadata.RELEASE_OR_SNAPSHOT) { ArtifactRepositoryPolicy policy = new ArtifactRepositoryPolicy(repository.getReleases()); policy.merge(repository.getSnapshots()); return policy; } else if ((nature & RepositoryMetadata.SNAPSHOT) != 0) { return repository.getSnapshots(); } else { return repository.getReleases(); } } }