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, 2010 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 1.3 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.