samples/src/main/java/com/datatorrent/samples/lib/math/ScriptSample.java

/**
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */
package com.datatorrent.samples.lib.math;

import com.datatorrent.api.StreamingApplication;
import com.datatorrent.api.DAG;
import com.datatorrent.lib.io.*;
import com.datatorrent.lib.script.JavaScriptOperator;
import org.apache.hadoop.conf.Configuration;

/**
 * This sample application code for showing sample usage of malhar operator(s). <br>
 * <b>Operator : </b> Script <br>
 * <bClass : </b> com.datatorrent.lib.math.Script
 * Java script returns square of variable 'val'.
 *
 * @since 0.3.2
 */
public class ScriptSample implements StreamingApplication
{
	@Override
	public void populateDAG(DAG dag, Configuration conf)
	{
		// Create application dag.
	    dag.setAttribute(DAG.APPLICATION_NAME, "MobileDevApplication");
	    dag.setAttribute(DAG.DEBUG, true);

	    // Add random integer generator operator
	    SingleKeyValMap rand = dag.addOperator("rand", SingleKeyValMap.class);

	    JavaScriptOperator script = dag.addOperator("script", JavaScriptOperator.class);
	    //script.setEval("val = val*val;");
	    script.addSetupScript("function square() { return val*val;}");
	    script.setInvoke("square");
	    dag.addStream("evalstream", rand.outport, script.inBindings);

	    // Connect to output console operator
	    ConsoleOutputOperator console = dag.addOperator("console", new ConsoleOutputOperator());
	    dag.addStream("rand_console",script.result , console.input);

	    // done
	}


}