/*******************************************************************************
* Copyright (c) 2000, 2010 IBM Corporation and others.
* All rights reserved. This program and the accompanying materials
* are made available under the terms of the Eclipse Public License v1.0
* which accompanies this distribution, and is available at
* http://www.eclipse.org/legal/epl-v10.html
*
* 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>
* 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();
}