/**
* Licensed to Cloudera, Inc. under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. Cloudera, Inc. 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.cloudera.flume.handlers.debug;
import java.io.IOException;
import com.cloudera.flume.conf.SourceFactory.SourceBuilder;
import com.cloudera.flume.core.Event;
import com.cloudera.flume.core.EventSource;
import com.google.common.base.Preconditions;
/**
* This source does absolutely nothing.
*/
public class NullSource extends EventSource.Base {
@Override
public void close() throws IOException {
}
@Override
/**
* Returning null means end of stream.
*/
public Event next() throws IOException {
return null;
}
@Override
public void open() throws IOException {
}
public static SourceBuilder builder() {
return new SourceBuilder() {
@Override
public EventSource build(String... argv) {
Preconditions.checkArgument(argv.length == 0, "usage: null");
return new NullSource();
}
};
}
}