GCJ-DBTOOL(1)								GNU							     GCJ-DBTOOL(1)

NAME

       gcj-dbtool - Manipulate class file mapping databases for libgcj

SYNOPSIS

       gcj-dbtool OPTION DBFILE [MORE] ...

       gcj-dbtool [-0] [-] [-n] [-a] [-f]
	 [-t] [-l] [-p [LIBDIR]]
	 [-v] [-m] [--version] [--help]

DESCRIPTION

       "gcj-dbtool" is a tool for creating and manipulating class file mapping databases.  "libgcj" can use these databases to find a shared
       library corresponding to the bytecode representation of a class.  This functionality is useful for ahead-of-time compilation of a program
       that has no knowledge of "gcj".

       "gcj-dbtool" works best if all the jar files added to it are compiled using "-findirect-dispatch".

       Note that "gcj-dbtool" is currently available as "preview technology".  We believe it is a reasonable way to allow application-transparent
       ahead-of-time compilation, but this is an unexplored area.  We welcome your comments.

OPTIONS

       -n DBFILE [SIZE]
	   This creates a new database.  Currently, databases cannot be resized; you can choose a larger initial size if desired.  The default
	   size is 32,749.

       -a DBFILE JARFILE LIB
       -f DBFILE JARFILE LIB
	   This adds a jar file to the database.  For each class file in the jar, a cryptographic signature of the bytecode representation of the
	   class is recorded in the database.  At runtime, a class is looked up by its signature and the compiled form of the class is looked for
	   in the corresponding shared library.  The -a option will verify that LIB exists before adding it to the database; -f skips this check.

       [-][-0] -m DBFILE DBFILE,[DBFILE]
	   Merge a number of databases.  The output database overwrites any existing database.	To add databases into an existing database,
	   include the destination in the list of sources.

	   If - or -0 are used, the list of files to read is taken from standard input instead of the command line.  For -0, Input filenames are
	   terminated by a null character instead of by whitespace.  Useful when arguments might contain white space.  The GNU find -print0 option
	   produces input suitable for this mode.

       -t DBFILE
	   Test a database.

       -l DBFILE
	   List the contents of a database.

       -p  Print the name of the default database.  If there is no default database, this prints a blank line.	If LIBDIR is specified, use it
	   instead of the default library directory component of the database name.

       --help
	   Print a help message, then exit.

       --version
       -v  Print version information, then exit.

SEE ALSO

       gcc(1), gcj(1), gcjh(1), jcf-dump(1), gfdl(7), and the Info entries for gcj and gcc.

COPYRIGHT

       Copyright (c) 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008 Free Software Foundation, Inc.

       Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.2 or
       any later version published by the Free Software Foundation; with no Invariant Sections, the Front-Cover Texts being (a) (see below), and
       with the Back-Cover Texts being (b) (see below).  A copy of the license is included in the man page gfdl(7).

       (a) The FSF's Front-Cover Text is:

	    A GNU Manual

       (b) The FSF's Back-Cover Text is:

	    You have freedom to copy and modify this GNU Manual, like GNU
	    software.  Copies published by the Free Software Foundation raise
	    funds for GNU development.

gcc-4.5 							    2010-07-05							     GCJ-DBTOOL(1)