The short description:

- write your java code, declaring one or more methods "native" and
 making sure the shared library that will contain the native methods
 is loaded before any native methods are invoked

- compile the java code

- run javah to get a header file containing native declarations of the
 native methods

- implement the native methods in e.g. C or C++ (or really any
 language with a C binding), using the header file as reference

- compile your native code to a shared library or DLL and put it where
 the JVM can find it, i.e. one of the places mentioned in
 java.library.path

If you want a more detailed explanation, start reading:

 http://www.amazon.com/exec/obidos/ASIN/0201325772
 http://www.amazon.com/exec/obidos/ASIN/0136798950
 http://java.sun.com/docs/books/tutorial/native1.1/index.html
 http://java.sun.com/j2se/1.5.0/docs/guide/jni/index.html

/gordon

If you use MS VC++ v7.1 you can test the tool at
http://simtel.net/product.php[id]90910[SiteID]simtel.net

see http://mindprod.com/jgloss/jni.html

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