Java plugins

Let's see it work

We will demonstrate just how easy it is to add new features to Stata using Java.

We are going to create a new Stata command tryjava. Here it is in action:

. tryjava
  hello from java!

.    _

First, write a hello routine in Java and save it in a .java file:

                              
 file HelloFromJava.java 
   
import com.stata.sfi.*;
public class HelloFromJava
{
        public static int sayhello(String[] args)
        {
               SFIToolkit.displayln("Hello from java!") ;
               return(0) ;      // Stata return code
        }
}

Compile the .java file using the Java compiler.

For this step, you may want to copy sfi-api.jar from your Stata installation to your current directory.

This produces a new file, HelloFromJava.class:

% javac -classpath sfi-api.jar HelloFromJava.java

Build a Java JAR file from this class file. You can name the JAR file whatever you wish. We will call it tryjava.jar:

% jar cvf tryjava.jar HelloFromJava.class

Copy the JAR file to your PERSONAL directory. (In Stata, type sysdir to find out where your PERSONAL directory is.)

Now write a Stata ado-file:

                              
 file tryjava.ado 
   
program tryjava
       version 18
       javacall HelloFromJava sayhello, jar(tryjava.jar)
end
                              
 file tryjava.ado 
 

That's it.