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  31 <p>
  32 This package provides methods to read files from a JAR file and
  33 to transform them to a more compact transfer format called Pack200.
  34 It also provides methods to receive the transmitted data and expand
  35 it into a JAR file equivalent to the original JAR file.
  36 
  37 <p>
  38 The <tt>pack</tt> methods may be used by application developers
  39 who wish to deploy large JARs on the web.  The <tt>unpack</tt> methods may be used
  40 by deployment applications such as Java Web Start and Java Plugin.
  41 
  42 <p>
  43 In typical use, the packed output should be further compressed using
  44 a suitable tool such as gzip or <tt>java.util.zip.GZIPOutputStream</tt>.
  45 The resulting file (with a suffix ".pack.gz") should be hosted on a HTTP/1.1
  46 compliant server, which will be capable of handling "Accept-Encoding",
  47 as specified by the HTTP 1.1 RFC2616 specification.
  48 
  49 <p>
  50 <b>NOTE:</b> It is recommended that the original ".jar" file be hosted
  51 in addition to the ".pack.gz" file, so that older client implementations
  52 will continue to work reliably.
  53 (On-demand compression by the server is not recommended.)
  54 
  55 <p>
  56 When a client application requests a ".jar" file (call it "Large.jar"),
  57 the client will transmit the  headers
  58 "Content-Type=application/x-java-archive" as well as "Accept-Encoding=pack200-gzip".
  59 This indicates to the server that the client application desires an version
  60 of the file encoded with Pack200 and further compressed with gzip.
  61 
  62 <p>
  63 The server implementation will typically check for the existence of "Large.pack.gz".
  64 If that file is available, the server will transmit it with the headers
  65 "Content-Encoding=pack200-gzip" and "Content-Type=application/x-java-archive".
  66 
  67 <p>
  68 If the ".pack.gz" file, is not available, then the server will transmit
  69 the original ".jar"
  70 with "Content-Encoding=null" and "Content-Type=application/x-java-archive".
  71 
  72 <p>
  73 A MIME type of "application/x-java-pack200" may be specified by the
  74 client application to indicate a ".pack" file is required.
  75 However, this has limited capability, and is not recommended.
  76 
  77 <h2> Package Specification</h2>
  78 Network Transfer Format Specification :<a href="http://jcp.org/en/jsr/detail?id=200">
  79 http://jcp.org/en/jsr/detail?id=200</a>
  80 
  81 <h2> Related Documentation</h2>
  82 For overviews, tutorials, examples, guides, and tool documentation, please
  83 see:
  84 <ul>
  85 
  86 <li>
  87 Jar File Specification :<a href="http://java.sun.com/j2se/1.3/docs/guide/jar/jar.html">
  88 http://java.sun.com/j2se/1.3/docs/guide/jar/jar.html</a></li>
  89 
  90 <li>
  91 Class File Specification: Chapter 4 of
  92 <em>The Java&trade; Virtual Machine Specification</em>
  93 
  94 <li>
  95 Hypertext Transfer Protocol -- HTTP/1.1 : <a href="http://www.ietf.org/rfc/rfc2616.txt">
  96 http://www.ietf.org/rfc/rfc2616.txt
  97 </ul>
  98 
  99 <li>
 100 @since 1.5</li>
 101 
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