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       java-wrappers - capacities shared by java wrapper scripts


       Most  Java  programs  are  not  run  directly,  but through small shell
       scripts that take care of various things, such as  finding  a  suitable
       java environment and looking for libraries.

       To  ease  the task of the maintainers, they rely on a library providing
       runtime detection, library detection and other  features.  This  manual
       page  describes  the common features of all those scripts, and to which
       point you can configure them.  This  is  mainly  done  via  environment


       java-wrappers understands some environment variables:

              The  java  command that will be run. If this variable is set, it
              disables all lookup for a java runtime.

              Specifies a directory that will be looked for a java  or  a  jdb
              executable  (depending on the setting of JAVA_DEBUGGER).  It has
              precedence over JAVA_HOME but not over JAVA_CMD.

              A path to a java runtime. If this variable is  set,  all  lookup
              for  a  java  runtime  is  disabled,  except  that  if  no  java
              executable is found in the path, the command java is used.

              A probably more easy-to-use version of the  JAVA_HOME  variable:
              instead  of  specifying  the  full path of the java runtime, you
              name it. List of available flavors can  be  found  in  the  file
              /usr/lib/java-wrappers/  See examples below.

              If  this is set, the wrapper will try to pick up a java debugger
              rather than a java interpreter. This will fail if the jbd of the
              runtime found is a stub.

              Additional  classpath,  will have priority over the one found by
              the wrapper.

              Additional arguments to the java command. They will come  before
              all other arguments.

              If  this  variable is set, it will be the only classpath.  You’d
              better know what you are doing.

              This is probably the most important variable;  if  it  set,  the
              wrapper  will  print  out  useful  information as it goes by its
              business, such as which runtime it did find, and  which  command
              is run eventually.

              The path where the wrappers will go looking for jar archives. If
              not set, the wrapper  will  look  into  the  default  directory,
              /usr/share/java.   Warning  : the wrapper will not look anywhere
              else than in JAVA_JARPATH.  Setting  it  incorrectly  will  most
              probably result in early crashes.


       The examples all rely on rasterizer(1), from the package libbatik-java,
       but they really apply to all scripts that use java-wrappers.

       Print out debugging information:

       DEBUG_WRAPPER=1 rasterizer

       Limit rasterizer’s memory to 80 MB:

       JAVA_ARGS=-Xmx80m rasterizer

       Force rasterizer to run with kaffe(1):

       JAVA_HOME=/usr/lib/kaffe rasterizer

       The same, but using JAVA_BINDIR:

       JAVA_BINDIR=/usr/lib/kaffe/bin rasterizer

       Force rasterizer to run with openjdk:

       JAVA_FLAVOR=openjdk rasterizer

       Debug  rasterizer  with  Sun’s  debugger,  while   printing   debugging
       information from the wrapper:

       DEBUG_WRAPPER=1 JAVA_CMD=/usr/lib/jvm/java-6-sun/bin/jdb rasterizer


       Care  has been taken to make the wrappers bug-free. If that was not the
       case, please file a bug report against the java-wrappers package.

       If you wish to submit any problem with a  java  executable  relying  on
       java-wrappers,  please  also  submit the output of the command run with
       DEBUG_WRAPPER=1.   It  will  save  one  mail  exchange  and   therefore
       potentially reduce the time it takes to fix the bug.


       There is currently no documentation about writing a wrapper script save
       the comments in /usr/lib/java-wrappers/  If  you  have
       to  write  one,  we  suggest  you base yourself upon, for instance, the
       rasterizer wrapper script, or any other one (just pick  up  any  direct
       reverse dependency of java-wrappers and look for scripts).


       java(1), jdb(1)



       java-wrappers  and  its  documentation were written by Vincent Fourmond