# Interacting with Java

Having mastered the principles of Mathematica's interaction with external programs, it will be easy to understand the principles of writing Java programs in Mathematica.

First, you need to enable the `JLink`

package. Here's an example Java program that will produce an expression computation using Mathematica's capabilities:

Similar to .NET, the following functions are used: `JavaBlock`

for procedure construction in Java language and `JavaNew`

to define a new object copy. The `Moving slider`

event is declared with the help of the `setHandler`

method.

After running the `RealTimeAlgebraModal[]`

command, you will see the following window where you can change the parameter value and a power series in the expansion by moving the slider:

Let's look at a simple example of how to use the computing capabilities of Mathematica in a program written in Java:

import com.wolfram.jlink.*; public class SampleProgram { public static void main(String[] argv) { KernelLink...