Example usage for javax.script ScriptEngine eval

Introduction

In this page you can find the example usage for javax.script ScriptEngine eval.

Prototype

public Object eval(Reader reader) throws ScriptException;

Source Link

Document

Same as eval(String) except that the source of the script is provided as a Reader

Usage

From source file:Main.java

public static void main(String[] args) {
    ScriptEngineManager manager = new ScriptEngineManager();
    ScriptEngine engine = manager.getEngineByName("js");
    engine.put("a", 1);
    engine.put("b", 2);
    try {// w w  w .  jav  a  2s  .c o  m
        String expression = "(a + b) > 2";
        Object result = engine.eval(expression);
        System.out.println(expression + " ? " + result);
    } catch (ScriptException se) {
        se.printStackTrace();
    }
}

From source file:Main.java

public static void main(String[] args) throws ScriptException {
    ScriptEngineManager manager = new ScriptEngineManager();
    ScriptEngine engine = manager.getEngineByName("JavaScript");
    Main result = new Main();
    engine.put("result", result);
    String script = "3 + 4; result.setValue(1);";
    engine.eval(script);
    int returnedValue = result.getValue();
    System.out.println("Returned value is " + returnedValue);
}

From source file:Main.java

public static void main(String[] args) {
    // Create a script engine manager
    ScriptEngineManager manager = new ScriptEngineManager();

    // Obtain a script engine from the manager
    ScriptEngine engine = manager.getEngineByName("JavaScript");

    // Store the script in a String
    String script = "print('hi from java2s.com!')";
    try {// w  ww . j a  va  2s.  co  m
        // Execute the script
        engine.eval(script);
    } catch (ScriptException e) {
        e.printStackTrace();
    }
}

From source file:Main.java

public static void main(String[] args) throws ScriptException {
    ScriptEngine jse = new ScriptEngineManager().getEngineByName("javascript");
    Bindings bindings = jse.getBindings(ScriptContext.ENGINE_SCOPE);
    Main test = new Main();
    bindings.put("test", test);
    String preFix = "demo";
    jse.eval("test." + preFix + "_test()");
    preFix = "actual";
    jse.eval("test." + preFix + "_test()");
}

From source file:TestCompilationSpeed.java

public static void main(String[] args) throws Exception {
    ScriptEngineManager manager = new ScriptEngineManager();
    ScriptEngine engine = manager.getEngineByName("JavaScript");

    String fact = "function fact (n){if (n == 0)return 1; else return n*fact (n-1);};";

    long time = System.currentTimeMillis();
    for (int i = 0; i < MAX_ITERATIONS; i++)
        engine.eval(fact);
    System.out.println(System.currentTimeMillis() - time);

    Compilable compilable = null;
    if (engine instanceof Compilable) {
        compilable = (Compilable) engine;
        CompiledScript script = compilable.compile(fact);

        time = System.currentTimeMillis();
        for (int i = 0; i < MAX_ITERATIONS; i++)
            script.eval();//  ww w  .ja v a2  s.  com
        System.out.println(System.currentTimeMillis() - time);
    }
}

From source file:Main.java

public static void main(String[] args) throws ScriptException {
    ScriptEngineManager manager = new ScriptEngineManager();
    ScriptEngine engine = manager.getEngineByName("JavaScript");

    manager.put("n1", 1);
    String script = "var sum = n1 + n2;print(msg + " + "' n1=' + n1 + ', n2=' + n2 + " + "', sum=' + sum);";

    engine.put("n2", 2);
    engine.put("msg", "a string");
    engine.eval(script);

    Bindings bindings = engine.createBindings();
    bindings.put("n2", 3);
    bindings.put("msg", "another string");
    engine.eval(script, bindings);/* w w  w  .  ja  v a 2  s . c om*/

    ScriptContext ctx = new SimpleScriptContext();
    Bindings ctxGlobalBindings = engine.createBindings();
    ctx.setBindings(ctxGlobalBindings, GLOBAL_SCOPE);
    ctx.setAttribute("n1", 4, GLOBAL_SCOPE);
    ctx.setAttribute("n2", 5, ENGINE_SCOPE);
    ctx.setAttribute("msg", "ScriptContext:", ENGINE_SCOPE);
    engine.eval(script, ctx);

    engine.eval(script);
}

From source file:Main.java

public static void main(String[] args) {
    // Get the script engine factory for Nashorn
    ScriptEngineManager manager = new ScriptEngineManager();
    ScriptEngine engine = manager.getEngineByName("JavaScript");
    ScriptEngineFactory factory = engine.getFactory();

    // Get the script
    String script = factory.getOutputStatement("\"java2s\"");
    System.out.println("Syntax: " + script);

    // Evaluate the script
    try {//from  ww w  .j av a2s.com
        engine.eval(script);
    } catch (ScriptException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }
}

From source file:Main.java

public static void main(String[] args) throws Exception {
    ScriptEngineManager manager = new ScriptEngineManager();
    ScriptEngine engine = manager.getEngineByName("JavaScript");
    if (!(engine instanceof Invocable)) {
        System.out.println("Invoking methods is not supported.");
        return;//  ww w. ja  v  a2s.  c  o m
    }
    Invocable inv = (Invocable) engine;
    String scriptPath = "c:/Java_Dev/calculator.js";

    engine.eval("load('" + scriptPath + "')");

    Object calculator = engine.get("calculator");

    int x = 3;
    int y = 4;
    Object addResult = inv.invokeMethod(calculator, "add", x, y);
    Object subResult = inv.invokeMethod(calculator, "subtract", x, y);
    Object mulResult = inv.invokeMethod(calculator, "multiply", x, y);
    Object divResult = inv.invokeMethod(calculator, "divide", x, y);

    System.out.println(addResult);
    System.out.println(subResult);
    System.out.println(mulResult);
    System.out.println(divResult);
}

From source file:Main.java

public static void main(String[] args) throws Exception {
    ScriptEngineManager manager = new ScriptEngineManager();
    ScriptEngine engine = manager.getEngineByName("JavaScript");

    if (!(engine instanceof Invocable)) {
        System.out.println("Interface implementation in script" + "is not supported.");
        return;/*from  w  w  w .  j a  v a 2  s.c o  m*/
    }
    Invocable inv = (Invocable) engine;
    String scriptPath = "c:/Java_Dev/cal.js";
    engine.eval("load('" + scriptPath + "')");
    Calculator calc = inv.getInterface(Calculator.class);
    if (calc == null) {
        System.err.println("Calculator interface " + "implementation not found.");
        return;
    }
    double x = 2.0;
    double y = 1.0;
    double addResult = calc.add(x, y);

    System.out.println(addResult);
}

From source file:Main.java

public static void main(String[] args) throws Exception {
    ScriptEngineManager manager = new ScriptEngineManager();
    ScriptEngine engine = manager.getEngineByName("js");
    engine.put("a", 1);
    engine.put("b", 5);

    Bindings bindings = engine.getBindings(ScriptContext.ENGINE_SCOPE);
    Object a = bindings.get("a");
    Object b = bindings.get("b");
    System.out.println("a = " + a);
    System.out.println("b = " + b);

    Object result = engine.eval("c = a + b;");
    System.out.println("a + b = " + result);
}