xenial (7) java-wrappers.7.gz

NAME

       java-wrappers - capacities shared by java wrapper scripts

DESCRIPTION

       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 variables.

ENVIRONMENT VARIABLES

       java-wrappers understands some environment variables:

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

       JAVA_BINDIR
              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.

       JAVA_HOME
              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.

       JAVA_FLAVOR
              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/jvm-list.sh.  See examples below.

       JAVA_DEBUGGER
              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.

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

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

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

       DEBUG_WRAPPER
              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.

       JAVA_JARPATH
              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.

EXAMPLES

       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

BUGS

       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.

DEVELOPERS

       There is currently no documentation about writing a wrapper script save the  comments  in  /usr/lib/java-
       wrappers/java-wrappers.sh.   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).

SEE ALSO

       java(1), jdb(1)

       /usr/lib/java-wrappers/java-wrappers.sh

AUTHOR

       java-wrappers and its documentation were written by Vincent Fourmond <fourmond@debian.org>