1extcheck(1) General Commands Manual extcheck(1)
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6 extcheck - A utility to detect jar conflicts
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8 extcheck detects version conflicts between a target jar file and cur‐
9 rently installed extension jar files.
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12 extcheck [ -verbose ] targetfile.jar
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16 The extcheck utility checks a specified Jar file for title and version
17 conflicts with any extensions installed in the Java(TM) SDK. Before
18 installing an extension, you can use this utility to see if the same or
19 a more recent version of the extension is already installed.
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21 The extcheck utility compares the Specification-title and Specifica‐
22 tion-version headers in the manifest of the targetfile.jar file against
23 the corresponding headers in all Jar files currently installed in the
24 extension directory. (The extension directory is jre/lib/ext by
25 default.) The extcheck utility compares version numbers in the same way
26 as the method java.lang.Package.isCompatibleWith.
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28 If no conflict is detected, the return code is 0.
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30 If the manifest of any jar file in the extensions directory has the
31 same Specification-title and the same or a newer Specification-version
32 number, a non-zero error code is returned. A non-zero error code is
33 also returned if targetfile.jar does not have the Specification-title
34 or Specification-version attributes in its manifest.
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37 -verbose
38 Lists Jar files in the extension directory as they are checked.
39 Additionally, manifest attributes of the target jar file and any
40 conflicting jar files are also reported.
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42 -Joption
43 Pass option to the Java virtual machine, where option is one of the
44 options described on the reference page for the java application
45 launcher. For example, -J-Xms48m sets the startup memory to 48
46 megabytes.
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49 jar
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51 05 Aug 2006 extcheck(1)