70 lines
3.7 KiB
HTML
70 lines
3.7 KiB
HTML
<?xml version="1.0" encoding="UTF-8"?>
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<!DOCTYPE html
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PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
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<html lang="en-us" xml:lang="en-us">
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<head>
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<meta name="DC.Type" content="reference" />
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<meta name="DC.Title" content="IFSKey class" />
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<meta name="abstract" content="If the Java program allows other programs access to a file at the same time, the Java program can lock bytes in the file for a period of time. During that time, the program has exclusive use of that section of the file." />
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<meta name="description" content="If the Java program allows other programs access to a file at the same time, the Java program can lock bytes in the file for a period of time. During that time, the program has exclusive use of that section of the file." />
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<meta name="copyright" content="(C) Copyright IBM Corporation 2006" />
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<meta name="DC.Rights.Owner" content="(C) Copyright IBM Corporation 2006" />
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<meta name="DC.Format" content="XHTML" />
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<meta name="DC.Identifier" content="ifskey" />
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<meta name="DC.Language" content="en-us" />
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<!-- All rights reserved. Licensed Materials Property of IBM -->
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<link rel="stylesheet" type="text/css" href="./ibmdita.css" />
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<link rel="stylesheet" type="text/css" href="./ic.css" />
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<title>IFSKey class</title>
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</head>
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<body id="ifskey"><a name="ifskey"><!-- --></a>
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<!-- Java sync-link --><script language="Javascript" src="../rzahg/synch.js" type="text/javascript"></script>
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<h1 class="topictitle1">IFSKey class</h1>
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<div><p>If the Java™ program allows other programs access to a file
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at the same time, the Java program can lock bytes in the file
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for a period of time. During that time, the program has exclusive use of that
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section of the file. </p>
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<div class="section"><p>When a lock is successful, the integrated file system classes
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return an <a href="javadoc/com/ibm/as400/access/IFSKey.html#NAVBAR_TOP">IFSKey</a> object. This object is supplied to the unlock()
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method to indicate which bytes to unlock. When the file is closed, the system
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unlocks all locks that are still on the file (the system does an unlock for
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every lock that the program did not unlock).</p>
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</div>
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<div class="section"><h4 class="sectiontitle">Example: Using IFSKey</h4><p>The following example shows
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how to use the IFSKey class.</p>
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<pre> // Create an AS400 object.
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AS400 sys = new AS400("mySystem.myCompany.com");
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// Open an input stream. This
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// constructor opens with share_all
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// so other programs can open this
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// file.
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IFSFileInputStream aFile =
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new IFSFileInputStream(sys,"/mydir1/mydir2/myfile");
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// Lock the first 1K bytes in the
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// file. Now no other instance can
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// read these bytes.
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IFSKey key = aFile.lock(1024);
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// Read the first 1K of the file.
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byte data[] = new byte[1024];
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aFile.read(data);
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// Unlock the bytes of the file.
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aFile.unlock(key);
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// Close the file.
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aFile.close();</pre>
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</div>
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</div>
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</body>
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</html> |