Bug 82804 Jar creation should use less memory
I noticed that the JarWriter will read the entire file it plans to store into memory. An optimization would be to stream the file directly into the JarOutputStream. The only catch is with STORED items which need the CRC32 computed. A penalty could be taken in that case to compute the CRC in a loop and then stream the file.
org.eclipse.jdt.ui/ui/org/eclipse/jdt/ui/jarpackager/JarPackageData.java
* Set whether a description of this JAR package must be saved
	 * to a file by a JAR description writer during the export operation.
	 * <p>
	 * The format is defined by the client who implements the
	 * reader/writer pair.
	 * </p>
	 * @param state a boolean containing the new state
	 * @see #getDescriptionLocation()
	 * @see IJarDescriptionWriter
	 */
	public void setSaveDescription(boolean state) {
		fSaveDescription= state;
	}
	
	/**
	 * Returns the location of file containing the description of a JAR.
	 * This location is inside the workspace.
	 * 
	 * @return	the path of the description file location,
	 * 			or <code>null</code> if none is specified
	 */
	public IPath getDescriptionLocation() {
		return fDescriptionLocation;
	}
	/**
	 * Set the location of the JAR description file.
	 * 
	 * @param descriptionLocation the path of location
	 */
	public void setDescriptionLocation(IPath descriptionLocation) {