javax.script.Bindings Java Examples

public static String expandTemplate(Reader reader, Map<String, Object> values) {
    StringWriter writer = new StringWriter();
    ScriptEngine eng = getScriptEngine();
    Bindings bind = eng.getContext().getBindings(ScriptContext.ENGINE_SCOPE);
    if (values != null) {
        bind.putAll(values);
    }
    bind.put(ENCODING_PROPERTY_NAME, Charset.defaultCharset().name());
    eng.getContext().setWriter(writer);
    try {
        eng.eval(reader);
    } catch (ScriptException ex) {
        Exceptions.printStackTrace(ex);
    }

    return writer.toString();
}
 

@Test
public void itCanEnableRequireInDifferentBindingsOnTheSameEngine() throws Throwable {
  NashornScriptEngine engine =
      (NashornScriptEngine) new ScriptEngineManager().getEngineByName("nashorn");
  Bindings bindings1 = new SimpleBindings();
  Bindings bindings2 = new SimpleBindings();

  Require.enable(engine, root, bindings1);

  assertNull(engine.getBindings(ScriptContext.ENGINE_SCOPE).get("require"));
  assertNotNull(bindings1.get("require"));
  assertNull(bindings2.get("require"));
  assertEquals("file1", ((Bindings) engine.eval("require('./file1')", bindings1)).get("file1"));

  try {
    engine.eval("require('./file1')", bindings2);
    fail();
  } catch (ScriptException ignored) {
  }

  Require.enable(engine, root, bindings2);
  assertNull(engine.getBindings(ScriptContext.ENGINE_SCOPE).get("require"));
  assertNotNull(bindings2.get("require"));
  assertEquals("file1", ((Bindings) engine.eval("require('./file1')", bindings2)).get("file1"));
}
 

@Override
public Object eval(ScriptContext context) throws ScriptException {
	// Only compile if necessary (should be only the first time!)
	if (cachedClazz == null) {
		try {
			FileWriter out;
			IOUtils.write(script, out = new FileWriter(file));
			out.flush();
			out.close();
			cachedClazz = engine.compileScript(file);
		} catch (Exception e) {
			throw new ScriptException(e);
		}
	}
	// Evaluate it
	Bindings bnd = context.getBindings(ScriptContext.ENGINE_SCOPE);
	bnd.put(ScriptEngine.FILENAME, file.getAbsolutePath());
	return engine.evalClass(cachedClazz, bnd);
}
 

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

    engine.put("x", "hello");
    // print global variable "x"
    engine.eval("print(x);");
    // the above line prints "hello"

    // Now, pass a different script context
    final ScriptContext newContext = new SimpleScriptContext();
    newContext.setBindings(engine.createBindings(), ScriptContext.ENGINE_SCOPE);
    final Bindings engineScope = newContext.getBindings(ScriptContext.ENGINE_SCOPE);

    // add new variable "x" to the new engineScope
    engineScope.put("x", "world");

    // execute the same script - but this time pass a different script context
    engine.eval("print(x);", newContext);
    // the above line prints "world"
}
 

@Test
public void testGetServiceProviderFromWrappedContext() throws Exception {

    final String SERVICE_PROVIDER_NAME = "service_provider_js_test";

    AuthenticationContext authenticationContext = new AuthenticationContext();
    authenticationContext.setServiceProviderName(SERVICE_PROVIDER_NAME);

    JsAuthenticationContext jsAuthenticationContext = new JsAuthenticationContext(authenticationContext);
    Bindings bindings = scriptEngine.getBindings(ScriptContext.GLOBAL_SCOPE);
    bindings.put("context", jsAuthenticationContext);

    Object result = scriptEngine.eval("context.serviceProviderName");
    assertNotNull(result);
    assertEquals(result, SERVICE_PROVIDER_NAME, "Service Provider name set in AuthenticationContext is not " +
        "accessible from JSAuthenticationContext");
}
 

private Object executeGremlinScript(String gremlinQuery) throws AtlasBaseException {
    GremlinGroovyScriptEngine scriptEngine = getGremlinScriptEngine();

    try {
        Bindings bindings = scriptEngine.createBindings();

        bindings.put("graph", getGraph());
        bindings.put("g", getGraph().traversal());

        Object result = scriptEngine.eval(gremlinQuery, bindings);

        return result;
    } catch (ScriptException e) {
        throw new AtlasBaseException(AtlasErrorCode.GREMLIN_SCRIPT_EXECUTION_FAILED, gremlinQuery);
    } finally {
        releaseGremlinScriptEngine(scriptEngine);
    }
}
 

private Bindings buildBindings(RuleContext ctx, FromDeviceMsg msg) {
  Bindings bindings = NashornJsEvaluator.getAttributeBindings(ctx.getDeviceMetaData().getDeviceAttributes());
  if (msg != null) {
    switch (msg.getMsgType()) {
    case POST_ATTRIBUTES_REQUEST:
      bindings = NashornJsEvaluator.updateBindings(bindings, (UpdateAttributesRequest) msg);
      break;
    case POST_TELEMETRY_REQUEST:
      TelemetryUploadRequest telemetryMsg = (TelemetryUploadRequest) msg;
      for (List<KvEntry> entries : telemetryMsg.getData().values()) {
        bindings = NashornJsEvaluator.toBindings(bindings, entries);
      }
    }
  }
  return bindings;
}
 

@Test
public void testUnsupportedWithBindings() throws ScriptException {
    // Unsupported Java classes end up as `null` in default bindings
    Bindings bindings = engine.createBindings();
    Object javaObject = new JavaObject();
    bindings.put("javaObject", javaObject);

    assertThat(bindings.get("javaObject"), nullValue());
    assertThat(engine.eval("javaObject", bindings), nullValue());

    assertThat(engine.eval("typeof javaObject", bindings), instanceOfWith(String.class, is("object")));
    assertThat(engine.eval("javaObject == null", bindings),
            instanceOfWith(Boolean.class, sameInstance(Boolean.TRUE)));
    assertThat(engine.eval("javaObject === void 0", bindings),
            instanceOfWith(Boolean.class, sameInstance(Boolean.FALSE)));
    assertThat(engine.eval("javaObject === null", bindings),
            instanceOfWith(Boolean.class, sameInstance(Boolean.TRUE)));
}
 

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

    engine.put("x", "hello");
    // print global variable "x"
    engine.eval("print(x);");
    // the above line prints "hello"

    // Now, pass a different script context
    final ScriptContext newContext = new SimpleScriptContext();
    newContext.setBindings(engine.createBindings(), ScriptContext.ENGINE_SCOPE);
    final Bindings engineScope = newContext.getBindings(ScriptContext.ENGINE_SCOPE);

    // add new variable "x" to the new engineScope
    engineScope.put("x", "world");

    // execute the same script - but this time pass a different script context
    engine.eval("print(x);", newContext);
    // the above line prints "world"
}
 

@Test
public void createBindingsTest() {
    final ScriptEngineManager m = new ScriptEngineManager();
    final ScriptEngine e = m.getEngineByName("nashorn");
    final Bindings b = e.createBindings();
    b.put("foo", 42.0);
    Object res = null;
    try {
        res = e.eval("foo == 42.0", b);
    } catch (final ScriptException | NullPointerException se) {
        se.printStackTrace();
        fail(se.getMessage());
    }

    assertEquals(res, Boolean.TRUE);
}
 

public static Object isNum( ScriptEngine actualContext, Bindings actualObject, Object[] ArgList,
  Object FunctionContext ) {

  if ( ArgList.length == 1 ) {
    try {
      if ( isNull( ArgList[0] ) ) {
        return null;
      } else if ( isUndefined( ArgList[0] ) ) {
        return undefinedValue;
      }
      double sArg1 = (Double) ArgList[0];
      if ( Double.isNaN( sArg1 ) ) {
        return Boolean.FALSE;
      } else {
        return Boolean.TRUE;
      }
    } catch ( Exception e ) {
      return Boolean.FALSE;
    }
  } else {
    throw new RuntimeException( "The function call isNum requires 1 argument." );
  }
}
 

public static String resolveIP( ScriptEngine actualContext, Bindings actualObject, Object[] ArgList,
  Object FunctionContext ) {
  String sRC = "";
  if ( ArgList.length == 2 ) {
    try {
      InetAddress addr = InetAddress.getByName( (String) ArgList[0] );
      if ( ( (String) ArgList[1] ).equals( "IP" ) ) {
        sRC = addr.getHostName();
      } else {
        sRC = addr.getHostAddress();
      }
      if ( sRC.equals( ArgList[0] ) ) {
        sRC = "-";
      }
    } catch ( Exception e ) {
      sRC = "-";
    }
  } else {
    throw new RuntimeException( "The function call resolveIP requires 2 arguments." );
  }

  return sRC;
}
 

public static String rpad( ScriptEngine actualContext, Bindings actualObject, Object[] ArgList,
                           Object FunctionContext ) {
  try {
    if ( ArgList.length == 3 ) {
      if ( isNull( ArgList, new int[] { 0, 1, 2 } ) ) {
        return null;
      } else if ( isUndefined( ArgList, new int[] { 0, 1, 2 } ) ) {
        return (String) undefinedValue;
      }
      String valueToPad = (String) ArgList[ 0 ];
      String filler = (String) ArgList[ 1 ];
      int size = (Integer) ArgList[ 2 ];

      while ( valueToPad.length() < size ) {
        valueToPad = valueToPad + filler;
      }
      return valueToPad;
    }
  } catch ( Exception e ) {
    throw new RuntimeException( "The function call rpad requires 3 arguments." );
  }
  return null;
}
 

@Test
public void shouldProperlyHandleBindings() throws Exception {
    final Graph graph = TinkerFactory.createClassic();
    final GraphTraversalSource g = graph.traversal();
    final ScriptEngine engine = new GremlinGroovyScriptEngine();
    engine.put("g", g);
    engine.put("marko", convertToVertexId(graph, "marko"));
    Assert.assertEquals(g.V(convertToVertexId(graph, "marko")).next(), engine.eval("g.V(marko).next()"));

    final Bindings bindings = engine.createBindings();
    bindings.put("g", g);
    bindings.put("s", "marko");
    bindings.put("f", 0.5f);
    bindings.put("i", 1);
    bindings.put("b", true);
    bindings.put("l", 100l);
    bindings.put("d", 1.55555d);

    assertEquals(engine.eval("g.E().has('weight',f).next()", bindings), g.E(convertToEdgeId(graph, "marko", "knows", "vadas")).next());
    assertEquals(engine.eval("g.V().has('name',s).next()", bindings), g.V(convertToVertexId(graph, "marko")).next());
    assertEquals(engine.eval("g.V().sideEffect{it.get().property('bbb',it.get().value('name')=='marko')}.iterate();g.V().has('bbb',b).next()", bindings), g.V(convertToVertexId(graph, "marko")).next());
    assertEquals(engine.eval("g.V().sideEffect{it.get().property('iii',it.get().value('name')=='marko'?1:0)}.iterate();g.V().has('iii',i).next()", bindings), g.V(convertToVertexId(graph, "marko")).next());
    assertEquals(engine.eval("g.V().sideEffect{it.get().property('lll',it.get().value('name')=='marko'?100l:0l)}.iterate();g.V().has('lll',l).next()", bindings), g.V(convertToVertexId(graph, "marko")).next());
    assertEquals(engine.eval("g.V().sideEffect{it.get().property('ddd',it.get().value('name')=='marko'?1.55555d:0)}.iterate();g.V().has('ddd',d).next()", bindings), g.V(convertToVertexId(graph, "marko")).next());
}
 

@Override
public boolean nextKeyValue() throws IOException {
    while (true) {
        if (!this.lineRecordReader.nextKeyValue()) return false;
        try {
            final Bindings bindings = this.engine.createBindings();
            final StarGraph graph = StarGraph.open();
            bindings.put(GRAPH, graph);
            bindings.put(LINE, this.lineRecordReader.getCurrentValue().toString());
            final StarGraph.StarVertex sv = (StarGraph.StarVertex) script.eval(bindings);
            if (sv != null) {
                final Optional<StarGraph.StarVertex> vertex = sv.applyGraphFilter(this.graphFilter);
                if (vertex.isPresent()) {
                    this.vertexWritable.set(vertex.get());
                    return true;
                }
            }
        } catch (final ScriptException e) {
            throw new IOException(e.getMessage());
        }
    }
}
 

@Override
public Object evaluate(final String expression, final Map<String, ?> values) throws ExpressionEvaluationException {
   LOG.debug("Evaluating JavaScript expression: {1}", expression);
   try {
      final Bindings scope = engine.createBindings();
      final StringBuilder localVars = new StringBuilder();
      for (final Entry<String, ?> entry : values.entrySet()) {

         // workaround for http://ruby.11.x6.nabble.com/undefined-local-variable-in-ScriptEngine-eval-tp3452553p3452557.html
         scope.put("$" + entry.getKey(), entry.getValue()); // register as global var
         localVars.append(entry.getKey()) // // reference as local var
            .append("=$") //
            .append(entry.getKey()) //
            .append("\n");
      }

      return engine.eval(localVars.toString() + expression, scope);
   } catch (final ScriptException ex) {
      throw new ExpressionEvaluationException("Evaluating JRuby expression failed: " + expression, ex);
   }
}
 

protected Object evaluate(String script, String language, Bindings bindings) {
    ScriptEngine scriptEngine = getEngineByName(language);
    try {
        return scriptEngine.eval(script, bindings);
    } catch (ScriptException e) {
        throw new ActivitiException("problem evaluating script: " + e.getMessage(), e);
    }
}
 

@Test
public void itCanLoadModulesSpecifyingOnlyTheFolderWhenPackageJsonHasAMainFile()
    throws Throwable {
  Folder dir = mock(Folder.class);
  when(dir.getFile("package.json")).thenReturn("{ \"main\": \"foo.js\" }");
  when(dir.getFile("foo.js")).thenReturn("exports.foo = 'foo';");
  when(root.getFolder("dir")).thenReturn(dir);
  assertEquals("foo", ((Bindings) require.require("./dir")).get("foo"));
}
 

private Bindings createBinding(Map<String, Object> vars,
        ScriptEngine scriptEngine) {
    Bindings binds = scriptEngine.createBindings();
    if (null != vars && !vars.isEmpty()) {
        binds.putAll(vars);
    }
    
    return binds;
}
 

/**
 * Test multi-threaded access to global lexically declared variables for shared script classes with multiple globals.
 */
@Test
public static void multiThreadedLetTest() throws ScriptException, InterruptedException {
    final NashornScriptEngineFactory factory = new NashornScriptEngineFactory();
    final ScriptEngine e = factory.getScriptEngine(LANGUAGE_ES6);
    final Bindings b = e.createBindings();
    final ScriptContext origContext = e.getContext();
    final ScriptContext newCtxt = new SimpleScriptContext();
    newCtxt.setBindings(b, ScriptContext.ENGINE_SCOPE);
    final String sharedScript = "foo";

    assertEquals(e.eval("let foo = 'original context';", origContext), null);
    assertEquals(e.eval("let foo = 'new context';", newCtxt), null);

    final Thread t1 = new Thread(new ScriptRunner(e, origContext, sharedScript, "original context", 1000));
    final Thread t2 = new Thread(new ScriptRunner(e, newCtxt, sharedScript, "new context", 1000));
    t1.start();
    t2.start();
    t1.join();
    t2.join();

    assertEquals(e.eval("foo = 'newer context';", newCtxt), "newer context");
    final Thread t3 = new Thread(new ScriptRunner(e, origContext, sharedScript, "original context", 1000));
    final Thread t4 = new Thread(new ScriptRunner(e, newCtxt, sharedScript, "newer context", 1000));

    t3.start();
    t4.start();
    t3.join();
    t4.join();

    assertEquals(e.eval(sharedScript), "original context");
    assertEquals(e.eval(sharedScript, newCtxt), "newer context");
}
 

public void method() throws ScriptException {
    // a context with a new global bindings, same engine bindings
    final ScriptContext sc = new SimpleScriptContext();
    final Bindings global = new SimpleBindings();
    sc.setBindings(global, ScriptContext.GLOBAL_SCOPE);
    sc.setBindings(engineBindings, ScriptContext.ENGINE_SCOPE);
    global.put("text", "methodText");
    String value = engine.eval("text", sc).toString();
    Assert.assertEquals(value, "methodText");
}
 

@Test
public void testConsStringFromMirror() throws ScriptException {
    final Bindings b = e.getBindings(ScriptContext.ENGINE_SCOPE);
    //final Map<Object, Object> m = new HashMap<>();
    e.eval("var x = 'f'; x += 'oo'; var obj = {x: x};");
    assertEquals("foo", ((JSObject)b.get("obj")).getMember("x"));
}
 

/**
 * Test multi-threaded access to primitive prototype properties for shared script classes with multiple globals.
 */
@Test
public static void multiThreadedPrimitiveTest() throws ScriptException, InterruptedException {
    final ScriptEngineManager m = new ScriptEngineManager();
    final ScriptEngine e = m.getEngineByName("nashorn");
    final Bindings b = e.createBindings();
    final ScriptContext origContext = e.getContext();
    final ScriptContext newCtxt = new SimpleScriptContext();
    newCtxt.setBindings(b, ScriptContext.ENGINE_SCOPE);

    final Object obj1 = e.eval("String.prototype.foo = 'original context';", origContext);
    final Object obj2 = e.eval("String.prototype.foo = 'new context';", newCtxt);
    assertEquals(obj1, "original context");
    assertEquals(obj2, "new context");
    final String sharedScript = "''.foo";

    final Thread t1 = new Thread(new ScriptRunner(e, origContext, sharedScript, "original context", 1000));
    final Thread t2 = new Thread(new ScriptRunner(e, newCtxt, sharedScript, "new context", 1000));
    t1.start();
    t2.start();
    t1.join();
    t2.join();

    final Object obj3 = e.eval("delete String.prototype.foo; Object.prototype.foo = 'newer context';", newCtxt);
    assertEquals(obj3, "newer context");
    final Thread t3 = new Thread(new ScriptRunner(e, origContext, sharedScript, "original context", 1000));
    final Thread t4 = new Thread(new ScriptRunner(e, newCtxt, sharedScript, "newer context", 1000));

    t3.start();
    t4.start();
    t3.join();
    t4.join();

    Assert.assertEquals(e.eval(sharedScript), "original context");
    Assert.assertEquals(e.eval(sharedScript, newCtxt), "newer context");
}
 

/**
 * Test multi-threaded access to global getters and setters for shared script classes with multiple globals.
 */
@Test
public static void getterSetterTest() throws ScriptException, InterruptedException {
    final ScriptEngineManager m = new ScriptEngineManager();
    final ScriptEngine e = m.getEngineByName("nashorn");
    final Bindings b = e.createBindings();
    final ScriptContext origContext = e.getContext();
    final ScriptContext newCtxt = new SimpleScriptContext();
    newCtxt.setBindings(b, ScriptContext.ENGINE_SCOPE);
    final String sharedScript = "accessor1";

    e.eval(new URLReader(ScopeTest.class.getResource("resources/gettersetter.js")), origContext);
    assertEquals(e.eval("accessor1 = 1;"), 1);
    assertEquals(e.eval(sharedScript), 1);

    e.eval(new URLReader(ScopeTest.class.getResource("resources/gettersetter.js")), newCtxt);
    assertEquals(e.eval("accessor1 = 2;", newCtxt), 2);
    assertEquals(e.eval(sharedScript, newCtxt), 2);


    final Thread t1 = new Thread(new ScriptRunner(e, origContext, sharedScript, 1, 1000));
    final Thread t2 = new Thread(new ScriptRunner(e, newCtxt, sharedScript, 2, 1000));

    t1.start();
    t2.start();
    t1.join();
    t2.join();

    assertEquals(e.eval(sharedScript), 1);
    assertEquals(e.eval(sharedScript, newCtxt), 2);
    assertEquals(e.eval("v"), 1);
    assertEquals(e.eval("v", newCtxt), 2);
}
 

@Test
public void testCanNotConvertArbitraryClassToMirror() {
    assertCanNotConvert(Double.class, Map.class);
    assertCanNotConvert(Double.class, Bindings.class);
    assertCanNotConvert(Double.class, JSObject.class);
    assertCanNotConvert(Double.class, ScriptObjectMirror.class);
}
 

/**
 * Note, calling this method modifies the underlying {@link ScriptEngine},
 * preventing concurrent use of the ScriptEngine (Nashorn's {@link ScriptEngine} and
 * {@link javax.script.CompiledScript} is thread-safe, but {@link Bindings} isn't).
 */
InvocableScriptAdapter prepareInvokableScript(final ScriptBindingsConfigurer bindingsConfigurer) {
    final Bindings bindings = createBindings(bindingsConfigurer);
    evalUnchecked(bindings);
    final ScriptEngine engine = getEngine();
    engine.setBindings(bindings, ScriptContext.ENGINE_SCOPE);
    return new InvocableScriptAdapter(scriptModel, engine);
}
 

public static Bindings convertListEntries(Bindings bindings, String attributesVarName,
    Collection<AttributeKvEntry> attributes) {
  Map<String, Object> attrMap = new HashMap<>();
  for (AttributeKvEntry attr : attributes) {
    if (!CLIENT_SIDE.equalsIgnoreCase(attr.getKey()) && !SERVER_SIDE.equalsIgnoreCase(attr.getKey())
        && !SHARED.equalsIgnoreCase(attr.getKey())) {
      bindings.put(attr.getKey(), getValue(attr));
    }
    attrMap.put(attr.getKey(), getValue(attr));
  }
  bindings.put(attributesVarName, attrMap);
  return bindings;
}
 

public void execute(Diagram d, String code) {
    try {
        Bindings b = bindings;
        b.put("graph", d);
        engine.eval(code, b);
    } catch (ScriptException ex) {
        Exceptions.printStackTrace(ex);
    }
}
 

public static Object quarter( ScriptEngine actualContext, Bindings actualObject, Object[] ArgList,
  Object FunctionContext ) {
  try {
    if ( ArgList.length == 1 ) {
      if ( isNull( ArgList[0] ) ) {
        return new Double( Double.NaN );
      } else if ( isUndefined( ArgList[0] ) ) {
        return undefinedValue;
      }
      java.util.Date dArg1 = (java.util.Date) ArgList[0];
      Calendar cal = Calendar.getInstance();
      cal.setTime( dArg1 );

      // Patch by Ingo Klose: calendar months start at 0 in java.
      int iMonth = cal.get( Calendar.MONTH );
      if ( iMonth <= 2 ) {
        return new Double( 1 );
      } else if ( iMonth <= 5 ) {
        return new Double( 2 );
      } else if ( iMonth <= 8 ) {
        return new Double( 3 );
      } else {
        return new Double( 4 );
      }
    } else {
      throw new RuntimeException( "The function call quarter requires 1 argument." );
    }
  } catch ( Exception e ) {
    throw new RuntimeException( e.toString() );
  }
}
 

/**
 * Test multi-threaded access to global lexically declared variables for shared script classes with multiple globals.
 */
@Test
public static void multiThreadedLetTest() throws ScriptException, InterruptedException {
    final NashornScriptEngineFactory factory = new NashornScriptEngineFactory();
    final ScriptEngine e = factory.getScriptEngine(LANGUAGE_ES6);
    final Bindings b = e.createBindings();
    final ScriptContext origContext = e.getContext();
    final ScriptContext newCtxt = new SimpleScriptContext();
    newCtxt.setBindings(b, ScriptContext.ENGINE_SCOPE);
    final String sharedScript = "foo";

    assertEquals(e.eval("let foo = 'original context';", origContext), null);
    assertEquals(e.eval("let foo = 'new context';", newCtxt), null);

    final Thread t1 = new Thread(new ScriptRunner(e, origContext, sharedScript, "original context", 1000));
    final Thread t2 = new Thread(new ScriptRunner(e, newCtxt, sharedScript, "new context", 1000));
    t1.start();
    t2.start();
    t1.join();
    t2.join();

    assertEquals(e.eval("foo = 'newer context';", newCtxt), "newer context");
    final Thread t3 = new Thread(new ScriptRunner(e, origContext, sharedScript, "original context", 1000));
    final Thread t4 = new Thread(new ScriptRunner(e, newCtxt, sharedScript, "newer context", 1000));

    t3.start();
    t4.start();
    t3.join();
    t4.join();

    assertEquals(e.eval(sharedScript), "original context");
    assertEquals(e.eval(sharedScript, newCtxt), "newer context");
}