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JVM Instructions 2
JVM Processing
pack200

Release 5.0 of Java includes a new hyper-compression format for JAR files known as pack200. It works only on JAR files and is able to compress the size as much as 90% for very dense JAR files.

The pack200 format is well-suited for slow networks and fast computers or for very large JAR files. For example, use of the pack200 format is estimated to save 12 terabytes per week of downloads at java.sun.com.

The pack200 tool creates a .pack file and the unpack200 tool unpacks a .pack file into a JAR file. Both tools accept several options, but here is a quick example of usage.

  pack200 -g name.pack name.jar

creates the highly compressed name.pack file from the name.jar file. Conversely,

  unpack200 name.pack name.jar

unpacks the packed file into a JAR file.

References and Web Resources

• pack200- JAR Packing tool
• java.util.jar.Pack200 - class specifications
• Pack200 and Compression - deployment guide

            Tech
DecimalFormat
  Demo 1
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System.out.printf
  Demo 3
CJ Format Class
  Demo 4   Demo 5
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           Physics
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Simpson Rule
  Demo 2
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