Calling c++ function in java

Hi,
I would like to know how I can modify c++ program so that I can use its(c++) functions in java.
the program is c++ ready-made and i would like to use its functions in a java package.
i read the turiols concerning this on java.sun.com but does that mean that i have append "jni.h", "JNIEXPORT", etc to the c++ file?
Hints shall be appreciated.
Thanks.

OK, thanks.I have tried the jni procedure but without success.
Is it possible for Java talk to native code (c++) via TCP/IP.
Please advice of any links/knowledge.
Thanks.
1. Strictly speaking, java does not operate on C++; it
operates on C functions. This is more than a quibble:
o JNI expects to call C functions, not methods of C++
objects.
o In fact, if you really just have functions, but they
are compiled as C++, then you will probably have to
declare C linkage.
2. Functions called from java must conform to JNI
calling conventions.
o In general, the starting point is to define how you
would like the object and native method to look in
java, then run jni.h to generate the appropriate C
header definitions, then write the C code.
o Functions called from java must exist in shared
libraries - on Windows, in dlls.
o Existing C function libraries are typically accessed
by writing a "wrapper" dll that implements the
required java interface and then calls the existing
library functions.
o In fact, a wrapper could actually instantiate C++
objects and call their methods.
3. You might care to look up something called JACE,
which some people claim can generate the kinds of
wrappers discussed here.

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Hope this explains.
I'm calling a function called lightParse() from the
method. But, I'm getting an error:
F:\Data>javac -classpath
xerces.jar;xalan.jar;classpath%; Test.java
Test.java:22: lightParse(java.lang.String) in Test
cannot be applied to ()
lightParse();
^
The scenario or code portion is :
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import java.awt.*;
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import javax.xml.parsers.DocumentBuilderFactory;
import org.w3c.dom.Document;
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JScrollPane listContainer;
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setSize(300, 300);
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first of all ... i don't know english very vell and sorry about it ..... then ...
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Calling c++ function in java

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