org.apache.apex.api.ControlAwareDefaultOutputPort Maven / Gradle / Ivy
/**
* 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.api;
import org.apache.apex.api.operator.ControlTuple;
import org.apache.hadoop.classification.InterfaceStability;
import com.datatorrent.api.ControlTupleEnabledSink;
import com.datatorrent.api.DefaultOutputPort;
import com.datatorrent.api.Sink;
/**
* Default implementation for an output port which can emit a @{@link ControlTuple}.
* The {@link #emitControl(ControlTuple)} method can be used to emit control tuples onto this output port
*
* @since 3.6.0
*/
@InterfaceStability.Evolving
public class ControlAwareDefaultOutputPort extends DefaultOutputPort
{
public ControlAwareDefaultOutputPort()
{
sink = ControlTupleEnabledSink.BLACKHOLE;
}
/**
* Allows the operator to emit a @{@link ControlTuple}
* @param {@link UserDefinedControlTuple}
*/
public void emitControl(ControlTuple tuple)
{
verifyOperatorThread();
((ControlTupleEnabledSink)sink).putControl(tuple);
}
public boolean isConnected()
{
return sink != ControlTupleEnabledSink.BLACKHOLE;
}
@Override
public void setSink(Sink