Java in a Nutshell, 5th Edition [Electronic resources] نسخه متنی

Synopsis

Description

javah generates C

header and source files
(

.h and

.c files) that are
used when implementing Java native methods in C. The preferred native
method interface changed between Java 1.0 and Java 1.1. In Java 1.1
and earlier,

javah generated files for old-style
native methods. In Java 1.1, the -jni option
specified that

javah should generate new-style
files. In Java 1.2 and later, this option is the default.

This section describes only how to use

javah . A
full description of how to implement Java native methods in C is
beyond the scope of this book.

Options

-bootclasspath

Specifies the path to search for
system classes. See

javac for further
discussion. Java 1.2 and later.

-classpath path

Specifies the path

javah uses to look up the classes named on the
command line. This option overrides any path specified by the
CLASSPATH environment variable. Prior to Java 1.2,
this option can specify the location of the system classes and
extensions. In Java 1.2 and later, it specifies only the location of
application classes. See -bootclasspath. See also

java for further discussion of the classpath.

-d directory

Specifies the directory into which

javah stores
the files it generates. By default, it stores them in the current
directory. This option cannot be used with -o.

-force

Causes

javah to always write output files, even
if they contain no useful content.

-help

Causes

javah to display a simple usage message
and exit.

-J javaopt

Passes the option

javaopt to the Java
interpreter.

-jni

Specifies that

javah
should output header files for use with the Java Native
Interface (JNI) rather than the old JDK 1.0 native interface. This
option is the default in Java 1.2 and later. See also
-old. Java 1.1 and later.

-o outputfile

Combines all output into a single file,
outputfile, instead of creating separate
files for each specified class.

-old

Outputs files for Java 1.0-style native methods. Prior to Java 1.2,
this was the default. See also -jni. Java 1.2 and
later.

-stubs

Generates

.c
stub files for the class or classes instead of header files. This
option is only for the Java 1.0 native methods interface. See
-old.

-trace

Specifies that

javah should include tracing
output commands in the stub files it generates. In Java 1.2 and
later, this option is obsolete and has been removed. In its place,
you can use the -verbose:jni option of the Java
interpreter.

-v ,

-verbose

Specifies verbose mode. Causes

javah to print
messages about what it is doing. In Java 1.2 and later,
-verbose is a synonym.

-version

Causes

javah to display its version number.

Environment

CLASSPATH

Specifies the default classpath

javah searches
to find the specified classes. See

java for a
further discussion of the classpath.

See also

java ,

javac