Bug 11314 Replace package name fragments should always be smaller
Build 20020214 If you enter "2~." in the 'Replace package name fragments with:' field in the preferences (Java->Work in progress), com.ibm.foobar is replaced with co~.ib~.foobar. I believe that package name compression should only replace a fragment if the compressed name is actually smaller. Thus com. would not be replaced in this example, since co~. is the same length, and contains less info.
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/viewsupport/JavaElementLabels.java
* Method names contain thrown exceptions.
	 * e.g. <code>foo throws IOException</code>
	 */
	public final static int M_EXCEPTIONS= 1 << 2;
	
	/**
	 * Method names contain return type (appended)
	 * e.g. <code>foo : int</code>
	 */
	public final static int M_APP_RETURNTYPE= 1 << 3;
	
	/**
	 * Method names contain return type (appended)
	 * e.g. <code>int foo</code>
	 */
	public final static int M_PRE_RETURNTYPE= 1 << 4;	
	/**
	 * Method names are fully qualified.
	 * e.g. <code>java.util.Vector.size</code>
	 */
	public final static int M_FULLY_QUALIFIED= 1 << 5;
	
	/**
	 * Method names are post qualified.
	 * e.g. <code>size - java.util.Vector</code>
	 */
	public final static int M_POST_QUALIFIED= 1 << 6;
	
	/**
	 * Initializer names are fully qualified.