Problems with MATLAB Engine API for Java

I am trying to compile this piece of code:

import com.mathworks.engine.*;

public class javaEvalFunc {
    public static void main(String[] args) throws Exception {
        MatlabEngine eng = MatlabEngine.startMatlab();
        eng.evalAsync("[X, Y] = meshgrid(-2:0.2:2);");
        eng.evalAsync("Z = X .* exp(-X.^2 - Y.^2);");
        Object[] Z = eng.getVariable("Z");
        eng.close();
        }
}

I found it on this web page: Java Engine

As you can see I need a reference to com.mathworks.engine.*;

This Page Info says that the .jar file that I need to Add is in this Path:

matlabroot/extern/engines/java/jar/engine.jar

But in my computer I just have a folder called phyton in this path

matlabroot/extern/engines

Where can I find the .jar file that I need ?

I am using Eclipse IDE by the way. thanks.

[Chibing Gng]

could you find a solution? I have the same problem. By the way, it is 2016b

[manan lalit]

I have the same issue. I used the code written by Manuel and ran it on Eclipse after adding the external Engine JAR file from MATLAB 2016b, and ran into the following error.

 Exception in thread "main" java.lang.NoClassDefFoundError: com/mathworks/mvm/MvmTerminatedException
  at application.Main.main(Main.java:7) 
Caused by: java.lang.ClassNotFoundException: com.mathworks.mvm.MvmTerminatedException

Can anyone help or have suggestions about what else I could try?

[Anushan Vasantharajah]

I also have the same problem. Any one know the answer? :( please guys give some idea to sole the problem.

Answer 1

[Guillaume]

It would help if you used the documentation that come with your version. In R2016a, you will find no mention of the java engine, and that's because it's been introduced in R2016 (See the release notes under advanced software development).

You will have to upgrade to R2016b.

Answer 2

[Bo Li]

With a simple test "example.java" like this:

import com.mathworks.engine.*;
public class CNN
{
    public static void main(String[] args) throws Exception{
        MatlabEngine eng = MatlabEngine.startMatlab();
        double[] a = {2.0 ,4.0, 6.0};
        double[] roots = eng.feval("sqrt", a);
        eng.close();
    }
}

Following commands work for me:

C:\JavaEngine\src>javac -classpath <matlabroot>\\extern\\engines\\java\\jar\\engine.jar
example.java
C:\JavaEngine\src>set PATH=<matlabroot>\\bin\\win64;%PATH%
C:\JavaEngine\src>java -classpath .;<matlabroot>\\extern\\engines\\java\\jar\\engine.jar
example