Java tutorial
package org.apache.maven.model.building; /* * 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 java.io.File; import java.io.IOException; import java.io.InputStream; import java.io.Reader; import java.util.Map; import javax.inject.Inject; import javax.inject.Named; import javax.inject.Singleton; import org.apache.maven.model.Model; import org.apache.maven.model.io.ModelReader; import org.apache.maven.model.locator.ModelLocator; import org.eclipse.sisu.Typed; /** * * Note: uses @Typed to limit the types it is available for injection to just ModelProcessor. * * This is because the ModelProcessor interface extends ModelLocator and ModelReader. If we * made this component available under all its interfaces then it could end up being injected * into itself leading to a stack overflow. * * A side-effect of using @Typed is that it translates to explicit bindings in the container. * So instead of binding the component under a 'wildcard' key it is now bound with an explicit * key. Since this is a default component this will be a plain binding of ModelProcessor to * this implementation type, ie. no hint/name. * * This leads to a second side-effect in that any @Inject request for just ModelProcessor in * the same injector is immediately matched to this explicit binding, which means extensions * cannot override this binding. This is because the lookup is always short-circuited in this * specific situation (plain @Inject request, and plain explicit binding for the same type.) * * The simplest solution is to use a custom @Named here so it isn't bound under the plain key. * This is only necessary for default components using @Typed that want to support overriding. * * As a non-default component this now gets a negative priority relative to other implementations * of the same interface. Since we want to allow overriding this doesn't matter in this case. * (if it did we could add @Priority of 0 to match the priority given to default components.) */ @Named("core-default") @Singleton @Typed(ModelProcessor.class) public class DefaultModelProcessor implements ModelProcessor { @Inject private ModelLocator locator; @Inject private ModelReader reader; public DefaultModelProcessor setModelLocator(ModelLocator locator) { this.locator = locator; return this; } public DefaultModelProcessor setModelReader(ModelReader reader) { this.reader = reader; return this; } @Override public File locatePom(File projectDirectory) { return locator.locatePom(projectDirectory); } @Override public Model read(File input, Map<String, ?> options) throws IOException { return reader.read(input, options); } @Override public Model read(Reader input, Map<String, ?> options) throws IOException { return reader.read(input, options); } @Override public Model read(InputStream input, Map<String, ?> options) throws IOException { return reader.read(input, options); } }