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jni java本地接口编程例子原代码,是java调用本地操作系统代码的接口

                                README

                       Shared Stubs JNI Example

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This directory contains an example demonstrating the use of shared
stubs for calling native code from Java(tm) applications.  For
instance, we show how you could call the function printf from the
standard C library with little work.

For more information about shared stubs, we encourage you to read the
source code in this directory; this is an annotated example! Start
with the file Main.java.

At the time of this writing, we have implemented shared stubs for
SPARC based Solaris(tm) and 32 bit Windows(tm) platforms.


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Contents
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We give a short description of the contents of this directory.  If you
are learning this example, and how it works, it might help to browse
the files in the order listed here.

    Main.java           Entry point to this example.  Shows how you
                        would call C functions such as printf, scanf,
			etc.

    makefile.solaris    Makefiles for compiling and running this
    makefile.win32      example on Solaris and Windows.

    CFunction.java      An abstraction for a C funtion.  Users will
                        create an instance of class CFunction, and then do
                        a "callXXX" operation on that instance to cause
                        the real C function to be called.

    CPointer.java	An abstraction for a C pointer that points to
			an arbitrary C type.  Think of an instance of
			CPointer as a something that represents a
			"void *". CPointer provides methods that let you
			indirect the "void *" and get at what is
			pointed at as a Java data type.

    CMalloc.java        Just a CPointer, but the CPointer represents a C
			pointer that has been malloc'ed on the C heap.
			Use this if you have to pass malloc()'ed
			memory to some CFunction.

    dispatch.c		Implementation of the shared stub native methods.
			
    dispatch_sparc.s	SPARC specific parts of dispatch.c.

    dispatch_x86.c	Win32/x86 specific parts of dispatch.c.


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Requirements
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To build and run this example you will need one of the following
operating systems: 

        - SPARC based Solaris 2.4 (or higher)
        - Windows NT 4.0
        - Windows 95

You will have to install JDK(tm) software, release 1.1 or higher.

On Solaris you will need a C compiler (cc or gcc), and tools "as",
"ld" and "make", available in /usr/ccs/bin.  On Windows, you will need
the utilities "nmake" and "cl" from the Microsoft Developer Studio
suite of products; however, it should be trivial to create a makefile
to run this example with other C compilers.


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Compiling and running
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On Solaris, if you have JDK software installed in /home/user/jdk,
type:

        % make -f makefile.solaris JDK=/home/user/jdk

On Win32, if you have JDK software installed in c:\jdk, type:

        C:\JNI_Example> nmake -f makefile.win32 JDK=c:\jdk

The default target runs the example, in addition to compiling it.
If you wish to only compile the example, specify the target "build"
explicitly at the make command line.


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Comments and feedback
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Please send comments about this example, and JNI in general, to the
alias "[e-mail]".  We welcome your feedback!  Folks on this
alias are developers, and will not be able to provide support, but
will read comments.

For support, please visit the Java(tm) Developer Connection at:
              http://java.sun.com/jdc

If you find any bugs in this example, please send email to the JNI
alias.  Please file JNI bug reports at:
              http://java.sun.com/cgi-bin/bugreport.cgi