extcheck(1) Basic Tools extcheck(1)
NAME
extcheck - Detects version conflicts between a target Java Archive (JAR) file and
currently installed extension JAR files.
SYNOPSIS
extcheck [options] targetfile.jar
options
The command-line options. See Options.
targetfile.jar
The target JAR file against which the currently installed extension JAR files are
compared to detect version conflicts.
DESCRIPTION
The extcheck command checks a specified JAR file for title and version conflicts with any
extensions installed in the Java SE SDK. Before installing an extension, you can use this
utility to see whether the same or a more recent version of the extension is already
installed.
The extcheck command compares the Specification-title and Specification-version headers in
the manifest of the targetfile.jar file against the corresponding headers in all JAR files
currently installed in the extension directory. By default, the extension directory is
jre/lib/ext on Oracle Solaris and \jre\lib\ext on Windows. The extcheck command compares
version numbers in the same way as the java.lang.Package.isCompatibleWith method.
If no conflict is detected, then the return code is 0.
If the manifest of any JAR file in the extensions directory has the same Specification-
title and the same or a newer Specification-version number, then a non-zero error code is
returned. A non-zero error code is also returned when targetfile.jar does not have the
Specification-title or Specification-version attributes in its manifest file.
OPTIONS
-verbose
Lists JAR files in the extension directory as they are checked. Additionally,
manifest attributes of the target JAR file and any conflicting JAR files are also
reported.
-Joption
Passes option to the Java Virtual Machine (JVM), where option is one of the options
described on the reference page for the Java launcher. For example, -J-Xms48m sets
the startup memory to 48 MB. See java(1).
SEE ALSO
o jar(1)
JDK 8 21 November 2013 extcheck(1)
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