1 <!doctype html public "-//w3c//dtd html 4.0 transitional//en"> 2 <html> 3 <head> 4 <!-- 5 6 Copyright (c) 2003, 2011, Oracle and/or its affiliates. All rights reserved. 7 DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 8 9 This code is free software; you can redistribute it and/or modify it 10 under the terms of the GNU General Public License version 2 only, as 11 published by the Free Software Foundation. Oracle designates this 12 particular file as subject to the "Classpath" exception as provided 13 by Oracle in the LICENSE file that accompanied this code. 14 15 This code is distributed in the hope that it will be useful, but WITHOUT 16 ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 17 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 18 version 2 for more details (a copy is included in the LICENSE file that 19 accompanied this code). 20 21 You should have received a copy of the GNU General Public License version 22 2 along with this work; if not, write to the Free Software Foundation, 23 Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 24 25 Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 26 or visit www.oracle.com if you need additional information or have any 27 questions. 28 --> 29 </head> 30 <body bgcolor="white"> 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™ 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> 101 102 <br><!-- Put @see and @since tags down here. --> 103 </body> 104 </html>