Automatically generated by Pod::Man 4.09 (Pod::Simple 3.35) Standard preamble: ========================================================================
NAMEgcj-dbtool - Manipulate class file mapping databases for libgcj
gcj-dbtool [-0] [-] [-n] [-a] [-f]
[-t] [-l] [-p [
[-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.
- -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 DBFILEJARFILELIB
- -f DBFILEJARFILELIB
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 LIBexists before adding it to the database; -f skips this check.
- [-][-0] -m DBFILEDBFILE,[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. TheGNUfind -print0 option produces input suitable for this mode.
- -t DBFILE
- Test a database.
- -l DBFILE
- List the contents of a database.
Print the name of the default database. If there is no default
database, this prints a blank line. If LIBDIRis specified, use it instead of the default library directory component of the database name.
- Print a help message, then exit.
- Print version information, then exit.
SEE ALSOgcc(1), gcj(1), gcjh(1), jcf-dump(1), gfdl(7), and the Info entries for gcj and gcc.
COPYRIGHTCopyright (c) 2001-2016 Free Software Foundation, Inc.
Permission is granted to copy, distribute and/or modify this document under the terms of the
A GNU Manual
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.