extcheck(1)                                                        extcheck(1)



NAME
       extcheck - jar conflict detection utility

SYNOPSIS
       extcheck [ -verbose ] [ -J ] targetfile.jar

DESCRIPTION
       The  extcheck utility checks a specified jar file for title and version
       conflicts with  any  extensions  installed  in  the  JDK(tm)  software.
       Before  installing an extension, you can use this utility to see if the
       same or a more recent version of the extension is already installed.

       The extcheck utility compares the  Specification-title  and  Specifica-
       tion-version headers in the manifest of the targetfile.jar file against
       the corresponding headers in all jar files currently installed  in  the
       extension  directory.   (The  extension  directory  is  jre/lib/ext  by
       default.) The extcheck utility compares version numbers in the same way
       as the method java.lang.Package.isCompatibleWith.

OPTIONS
       The following options are supported:

       -verbose       Lists  jar  files in the extension directory as they are
                      checked.  Additionally, manifest attributes of the  tar-
                      get  jar  file  and  any  conflicting jar files are also
                      reported.

       -J  option     Pass option to the Java virtual machine, where option is
                      one  of  the  options  described on the man page for the
                      java application launcher,  java(1).  For  example,  -J-
                      Xms48m  sets the startup memory to 48 megabytes. It is a
                      common convention for -J to pass options to the underly-
                      ing virtual machine.

EXIT STATUS
       The following exit values are returned:

       00              No conflict is detected.

       non-zero       If  the  manifest  of any of the jar files in the exten-
                      sions directory has the same Specification-title and the
                      same or a newer Specification-version number, or if tar-
                      getfile.jar does not  have  the  Specification-title  or
                      Specification-version attributes in its manifest.

SEE ALSO
       jar(1)



                                 14 July 2000                      extcheck(1)