How to use

getInstalledContainerEntry

method

in

org.eclipse.jst.j2ee.internal.common.classpath.J2EEComponentClasspathContainerUtils

/**
 * Returns the existing classpath container if it is already on the classpath. This will not
 * create a new container.
 * 
 * @param jproj
 * @param classpathContainerID
 * @return
 */
public IClasspathEntry getExistingContainer(IJavaProject jproj, IPath classpathContainerPath) {
  return J2EEComponentClasspathContainerUtils.getInstalledContainerEntry(jproj, classpathContainerPath);
}

public static IClasspathContainer getInstalledContainer(IProject project, IPath containerPath) {
  IJavaProject jproj = JavaCore.create(project);
  IClasspathEntry entry = getInstalledContainerEntry(jproj, containerPath);
  IClasspathContainer container = null;
  if (entry != null) {
    try {
      container = JavaCore.getClasspathContainer(containerPath, jproj);
    } catch (JavaModelException e) {
      J2EEPlugin.getDefault().getLogger().logError(e);
    }
  }
  return container;
}