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javah(1)			  Basic	Tools			      javah(1)

NAME
       javah - Generates C header and source files from	a Java class.

SYNOPSIS
       javah [ options ] fully-qualified-class-name ...

       options
	      The command-line options.	See Options.

       fully-qualified-class-name
	      The fully	qualified location of the classes to be	converted to C
	      header and source	files.

DESCRIPTION
       The javah command generates C header and	source files that are needed
       to implement native methods. The	generated header and source files are
       used by C programs to reference an object's instance variables from
       native source code. The .h file contains	a struct definition with a
       layout that parallels the layout	of the corresponding class. The	fields
       in the struct correspond	to instance variables in the class.

       The name	of the header file and the structure declared within it	are
       derived from the	name of	the class. When	the class passed to the	javah
       command is inside a package, the	package	name is	added to the beginning
       of both the header file name and	the structure name. Underscores	(_)
       are used	as name	delimiters.

       By default the javah command creates a header file for each class
       listed on the command line and puts the files in	the current directory.
       Use the -stubs option to	create source files. Use the -o	option to
       concatenate the results for all listed classes into a single file.

       The Java	Native Interface (JNI) does not	require	header information or
       stub files. The javah command can still be used to generate native
       method function prototypes needed for JNI-style native methods. The
       javah command produces JNI-style	output by default and places the
       result in the .h	file.

OPTIONS
       -o outputfile
	      Concatenates the resulting header	or source files	for all	the
	      classes listed on	the command line into an output	file. Only one
	      of -o or -d can be used.

       -d directory
	      Sets the directory where the javah command saves the header
	      files or the stub	files. Only one	of -d or -o can	be used.

       -stubs
	      Causes the javah command to generate C declarations from the
	      Java object file.

       -verbose
	      Indicates	verbose	output and causes the javah command to print a
	      message to stdout	about the status of the	generated files.

       -help
	      Prints a help message for	javah usage.

       -version
	      Prints javah command release information.

       -jni
	      Causes the javah command to create an output file	containing
	      JNI-style	native method function prototypes. This	is the default
	      output; use of -jni is optional.

       -classpath path
	      Specifies	the path the javah command uses	to look	up classes.
	      Overrides	the default or the CLASSPATH environment variable when
	      it is set. Directories are separated by colons on	Oracle Solaris
	      and semicolons on	Windows. The general format for	path is:

	      Oracle Solaris:

	      .:your-path

	      Example: .:/home/avh/classes:/usr/local/share/java/classes

	      Windows:

	      .;your-path

	      Example: .;C:\users\dac\classes;C:\tools\java\classes

	      As a special convenience,	a class	path element that contains a
	      base name	of * is	considered equivalent to specifying a list of
	      all the files in the directory with the extension	.jar or	.JAR.

	      For example, if directory	mydir contains a.jar and b.JAR,	then
	      the class	path element mydir/* is	expanded to a A.jar:b.JAR,
	      except that the order of jar files is unspecified. All JAR files
	      in the specified directory, including hidden ones, are included
	      in the list. A class path	entry that consists of * expands to a
	      list of all the JAR files	in the current directory. The
	      CLASSPATH	environment variable, where defined, is	similarly
	      expanded.	Any class path wild card expansion occurs before the
	      Java Virtual Machine (JVM) is started. A Java program will never
	      see unexpanded wild cards	except by querying the environment.
	      For example, by calling System.getenv("CLASSPATH").

       -bootclasspath path
	      Specifies	the path from which to load bootstrap classes. By
	      default, the bootstrap classes are the classes that implement
	      the core Java platform located in	jre\lib\rt.jar and several
	      other JAR	files.

       -old
	      Specifies	that old JDK 1.0-style header files should be
	      generated.

       -force
	      Specifies	that output files should always	be written.

       -Joption
	      Passes option to the Java	Virtual	Machine, where option is one
	      of the options described on the reference	page for the Java
	      application launcher. For	example, -J-Xms48m sets	the startup
	      memory to	48 MB. See java(1).

SEE ALSO
       o javah(1)

       o java(1)

       o jdb(1)

       o javap(1)

       o javadoc(1)

JDK 8			       21 November 2013			      javah(1)

NAME | SYNOPSIS | DESCRIPTION | OPTIONS | SEE ALSO

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