import junit.framework.TestCase;

import javax.script.ScriptEngine;

import javax.script.ScriptEngineManager;

import javax.script.ScriptException;

import javax.swing.JButton;

import java.io.IOException;

import java.io.InputStream;

import java.io.InputStreamReader;

import java.util.stream.Collectors;

public class CallJs extends TestCase {

public void testConsoleLog() throws ScriptException {

    ScriptEngine engine = new ScriptEngineManager().getEngineByExtension("js");

    //此处会抛出异常，Java的script引擎并不包含console对象

    engine.eval("console.log('hello world')");

}

public void testConsoleLog2() throws ScriptException {

    ScriptEngine engine = new ScriptEngineManager().getEngineByExtension("js");

    engine.put("console", System.out);

    //此处会抛出异常，Java的script引擎并不包含console对象

    engine.eval("console.println('hello world')");

}

public void testUseJsFunction() throws ScriptException {

    ScriptEngine engine = new ScriptEngineManager().getEngineByExtension("js");

    engine.eval("function add(x,y){return x+y}");

    Object value = engine.eval("add(3,7)");

    System.out.println(value.getClass() + " " + value);

}

/**

 * 注意，这个内部类必须是public否则js编译器看不见

 */

public class SubWrapper {

    public int sub(int x, int y) {

        return x - y;

    }

}

public void testUseJsFile() throws IOException, ScriptException {

    ScriptEngine engine = new ScriptEngineManager().getEngineByExtension("js");

    InputStream cin = getClass().getResourceAsStream("/calljs.js");

    InputStreamReader reader = new InputStreamReader(cin);

    engine.put("subWrapper", new SubWrapper());

    engine.eval(reader);

    engine.put("console", System.out);

    System.out.println(engine.eval("add(3,4)"));

    System.out.println(engine.eval("sub(5,6)"));

}

public void testUpdateJavaObject() throws ScriptException {

    JButton button = new JButton();

    ScriptEngine engine = new ScriptEngineManager().getEngineByExtension("js");

    engine.put("button", button);

    engine.eval("button.text='hello world'");

    System.out.println(button.getText());

}

public void testlistAllScriptEngine() {

    //列出全部脚本引擎

    new ScriptEngineManager().getEngineFactories().forEach(fac -> {

        System.out.println("name " + fac.getEngineName()

                + "\nlanguage " + fac.getLanguageName()

                + "\nversion " + fac.getEngineVersion()

                + "\nlanguageVersion " + fac.getLanguageVersion()

                + "\nextensions " + fac.getExtensions().stream().collect(Collectors.joining(","))

                + "\nmimetypes " + fac.getMimeTypes().stream().collect(Collectors.joining(","))

                + "\n"

        );

    });

}

}

js

function add(x, y) {

    return x + y

}

function sub(x,y){

    return subWrapper.sub(x,y)

}