Java tutorial
/******************************************************************************* * Copyright (c) 2000, 2019 IBM Corporation and others. * * This program and the accompanying materials * are made available under the terms of the Eclipse Public License 2.0 * which accompanies this distribution, and is available at * https://www.eclipse.org/legal/epl-2.0/ * * SPDX-License-Identifier: EPL-2.0 * * Contributors: * IBM Corporation - initial API and implementation *******************************************************************************/ package org.eclipse.jdt.core; import org.eclipse.core.runtime.IPath; /** * Interface of a classpath container. * A classpath container provides a way to indirectly reference a set of classpath entries through * a classpath entry of kind <code>CPE_CONTAINER</code>. Typically, a classpath container can * be used to describe a complex library composed of multiple JARs or projects, considering also * that containers can map to different set of entries on each project, in other words, several * projects can reference the same generic container path, but have each of them actually bound * to a different container object. * <p> * The set of entries associated with a classpath container may contain any of the following: * <ul> * <li> library entries (<code>CPE_LIBRARY</code>) </li> * <li> project entries (<code>CPE_PROJECT</code>) </li> * </ul> * In particular, a classpath container can neither reference further classpath containers or classpath variables. * <p> * A library entry can reference other libraries through the Class-Path section of the JAR's MANIFEST.MF file. If the * container wants such referenced entries to be part of the classpath, the container must explicitly add them to the * array returned from {@link #getClasspathEntries()}. * <p> * Classpath container values are persisted locally to the workspace, but are not preserved from a * session to another. It is thus highly recommended to register a <code>ClasspathContainerInitializer</code> * for each referenced container (through the extension point "org.eclipse.jdt.core.ClasspathContainerInitializer"). * <p> * @see IClasspathEntry * @since 2.0 */ public interface IClasspathContainer { /** * Kind for a container mapping to an application library */ int K_APPLICATION = 1; /** * Kind for a container mapping to a system library */ int K_SYSTEM = 2; /** * Kind for a container mapping to a default system library, implicitly contributed by the runtime */ int K_DEFAULT_SYSTEM = 3; /** * Answers the set of classpath entries this container is mapping to. * <p> * The set of entries associated with a classpath container may contain any of the following: * <ul> * <li> library entries (<code>CPE_LIBRARY</code>) </li> * <li> project entries (<code>CPE_PROJECT</code>) </li> * </ul> * A classpath container can neither reference further classpath containers * or classpath variables. * <p> * A library entry can reference other libraries through the Class-Path section of the JAR's MANIFEST.MF file. If * the container wants such referenced entries to be part of the classpath, the container must explicitly add them * to the result. * <p> * This method is called by the Java model when it needs to resolve this * classpath container entry into a list of library and project entries. * The method is typically called exactly once for a given Java project, * and the resulting list of entries cached internally by the Java model. * This method must not be called by other clients. * <p> * There are a wide variety of conditions under which this method may be * invoked. To ensure that the implementation does not interfere with * correct functioning of the Java model, the implementation should use * only the following Java model APIs: * <ul> * <li>{@link JavaCore#newLibraryEntry(IPath, IPath, IPath, boolean)} and variants</li> * <li>{@link JavaCore#newProjectEntry(IPath, boolean)} and variants</li> * <li>{@link JavaCore#create(org.eclipse.core.resources.IWorkspaceRoot)}</li> * <li>{@link JavaCore#create(org.eclipse.core.resources.IProject)}</li> * <li>{@link JavaCore#getReferencedClasspathEntries(IClasspathEntry, IJavaProject)} with <code>null</code> as project</li> * <li>{@link IJavaModel#getJavaProjects()}</li> * <li>{@link IJavaProject#getRawClasspath()}</li> * <li>{@link IJavaProject#readRawClasspath()}</li> * <li>{@link IJavaProject#getOutputLocation()}</li> * <li>{@link IJavaProject#readOutputLocation()}</li> * <li>Java element operations marked as "handle-only"</li> * </ul> * <p> * The effects of using other Java model APIs are unspecified. * </p> * * @return IClasspathEntry[] - the classpath entries this container represents * @see IClasspathEntry */ IClasspathEntry[] getClasspathEntries(); /** * Answers a readable description of this container * * @return String - a string description of the container */ String getDescription(); /** * Answers the kind of this container. Can be either: * <ul> * <li><code>K_APPLICATION</code> if this container maps to an application library</li> * <li><code>K_SYSTEM</code> if this container maps to a system library</li> * <li><code>K_DEFAULT_SYSTEM</code> if this container maps to a default system library (library * implicitly contributed by the runtime).</li> * </ul> * Typically, system containers should be placed first on a build path. * @return the kind of this container */ int getKind(); /** * Answers the container path identifying this container. * A container path is formed by a first ID segment followed with extra segments, which * can be used as additional hints for resolving to this container. * <p> * The container ID is also used to identify a<code>ClasspathContainerInitializer</code> * registered on the extension point "org.eclipse.jdt.core.classpathContainerInitializer", which can * be invoked if needing to resolve the container before it is explicitly set. * <p> * @return IPath - the container path that is associated with this container */ IPath getPath(); }