For example, the effect of this option is built in: pack.class.attribute.SourceFile=RUH.

The special strings Pack200.Packer.ERROR, Pack200.Packer.STRIP, and Pack200.Packer.PASS are also allowed, with the same meaning as Pack200.Packer.UNKNOWN_ATTRIBUTE. This provides a way for users to request that specific attributes be refused, stripped, or passed bitwise (with no class compression).

Code like this might be used to support attributes for JCOV:

     Map p = packer.properties();
     p.put(CODE_ATTRIBUTE_PFX+"CoverageTable",       "NH[PHHII]");
     p.put(CODE_ATTRIBUTE_PFX+"CharacterRangeTable", "NH[PHPOHIIH]");
     p.put(CLASS_ATTRIBUTE_PFX+"SourceID",           "RUH");
     p.put(CLASS_ATTRIBUTE_PFX+"CompilationID",      "RUH");
 

Code like this might be used to strip debugging attributes:

     Map p = packer.properties();
     p.put(CODE_ATTRIBUTE_PFX+"LineNumberTable",    STRIP);
     p.put(CODE_ATTRIBUTE_PFX+"LocalVariableTable", STRIP);
     p.put(CLASS_ATTRIBUTE_PFX+"SourceFile",        STRIP);
 

If this property is set to the special string Pack200.Packer.KEEP, the packer will attempt to determine an independent deflation hint for each available element of the input archive, and transmit this hint separately.

The default is Pack200.Packer.KEEP, which preserves the input information, but may cause the transmitted archive to be larger than necessary.

It is up to the unpacker implementation to take action upon the hint to suitably compress the elements of the resulting unpacked jar.

The deflation hint of a ZIP or JAR element indicates whether the element was deflated or stored directly.

The special value 0 instructs the packer to copy through the original JAR file directly, with no compression. The JSR 200 standard requires any unpacker to understand this special case as a pass-through of the entire archive.

The default is 5, investing a modest amount of time to produce reasonable compression.

If it is set to Pack200.Packer.FALSE, the packer may reorder elements, and also remove JAR directory entries, which carry no useful information for Java applications. (Typically this enables better compression.)

The default is Pack200.Packer.TRUE, which preserves the input information, but may cause the transmitted archive to be larger than necessary.

This can marginally decrease the transmitted size of the archive, at the expense of setting all installed files to a single date.

If this property is set to the special string Pack200.Packer.KEEP, the packer transmits a separate modification time for each input element.

The default is Pack200.Packer.KEEP, which preserves the input information, but may cause the transmitted archive to be larger than necessary.

It is up to the unpacker implementation to take action to suitably set the modification time of each element of its output file.
See Also: Pack200.Packer.SEGMENT_LIMIT,

There is no pathname transformation, except that the system file separator is replaced by the JAR file separator '/'.

The resulting file names must match exactly as strings with their occurrences in the JAR file.

If a property value is a directory name, all files under that directory will be passed also.

Examples:

     Map p = packer.properties();
     p.put(PASS_FILE_PFX+0, "mutants/Rogue.class");
     p.put(PASS_FILE_PFX+1, "mutants/Wolverine.class");
     p.put(PASS_FILE_PFX+2, "mutants/Storm.class");
     # Pass all files in an entire directory hierarchy:
     p.put(PASS_FILE_PFX+3, "police/");
 

At a minimum, the unpacker must set progress to 0 at the beginning of a packing operation, and to 100 at the end.
See Also: Pack200.Packer.addPropertyChangeListener(java.beans.PropertyChangeListener),

As a special case, a value of -1 will produce a single large segment with all input files, while a value of 0 will produce one segment for each class. Larger archive segments result in less fragmentation and better compression, but processing them requires more memory.

The size of each segment is estimated by counting the size of each input file to be transmitted in the segment, along with the size of its name and other transmitted properties.

The default is 1000000 (a million bytes). This allows input JAR files of moderate size to be transmitted in one segment. It also puts a limit on memory requirements for packers and unpackers.

A 10Mb JAR packed without this limit will typically pack about 10% smaller, but the packer may require a larger Java heap (about ten times the segment limit).

The string Pack200.Packer.ERROR means that the pack operation as a whole will fail, with an exception of type IOException. The string Pack200.Packer.STRIP means that the attribute will be dropped. The string Pack200.Packer.PASS means that the whole class-file will be passed through (as if it were a resource file) without compression, with a suitable warning. This is the default value for this property.

Examples:

     Map p = pack200.getProperties();
     p.put(UNKNOWN_ATTRIBUTE, ERROR);
     p.put(UNKNOWN_ATTRIBUTE, STRIP);
     p.put(UNKNOWN_ATTRIBUTE, PASS);