content: /**
   * 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 org.apache.apex.malhar.contrib.jython;
  
  import java.util.HashMap;
  import java.util.Iterator;
  import java.util.Map;
  
  import org.python.core.PyCode;
  import org.python.core.PyIterator;
  import org.python.core.PyObject;
  import org.python.core.PyStringMap;
  import org.python.core.PyTuple;
  import org.python.util.PythonInterpreter;
  
  import org.apache.apex.malhar.lib.script.ScriptOperator;
  
  import com.datatorrent.api.Context.OperatorContext;
  
  /**
   * An operator that executes a python script and passes the input as bindings.
   * <p></p>
   * @displayName Python
   * @category Scripting
   * @tags python, script
   *
   * @since 0.3.3
   */
  public class PythonOperator extends ScriptOperator
  {
    /**
     * Python script interpretor.
     */
    private PythonInterpreter interp = new PythonInterpreter();
    private PyObject evalResult;
    private PyCode code;
  
    // Constructor
    public PythonOperator()
    {
      interp.exec("import sys");
    }
  
    @Override
    public void setup(OperatorContext context)
    {
      for (String s : setupScripts) {
        interp.exec(s);
      }
      code = interp.compile(script);
    }
  
    @Override
    public void process(Map<String, Object> tuple)
    {
      for (Map.Entry<String, Object> entry : tuple.entrySet()) {
        interp.set(entry.getKey(), entry.getValue());
      }
      evalResult = interp.eval(code);
      if (isPassThru) {
        if (result.isConnected()) {
          result.emit(evalResult);
        }
        if (outBindings.isConnected()) {
          outBindings.emit(new HashMap<String, Object>(getBindings()));
        }
      }
    }
  
    @Override
    public void endWindow()
    {
      if (!isPassThru) {
        result.emit(evalResult);
        outBindings.emit(new HashMap<String, Object>(getBindings()));
      }
    }
  
    @Override
    public Map<String, Object> getBindings()
    {
      Map<String, Object> bindings = new HashMap<String, Object>();
      PyStringMap keyValueMap = (PyStringMap)interp.getLocals();
      PyIterator keyValueSet = (PyIterator)keyValueMap.iteritems();
      for (Object temp : keyValueSet) {
        PyTuple tempEntry = (PyTuple)temp;
        Iterator<PyObject> iter = tempEntry.iterator();
        bindings.put((String)iter.next().__tojava__(String.class), iter.next());
      }
      return bindings;
    }
  
  }
  