NullContext.java
上传用户:quxuerui
上传日期:2018-01-08
资源大小:41811k
文件大小:2k
- /*
- * NullContext.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 org.apache.hadoop.metrics.spi;
- /**
- * Null metrics context: a metrics context which does nothing. Used as the
- * default context, so that no performance data is emitted if no configuration
- * data is found.
- *
- */
- public class NullContext extends AbstractMetricsContext {
-
- /** Creates a new instance of NullContext */
- public NullContext() {
- }
-
- /**
- * Do-nothing version of startMonitoring
- */
- public void startMonitoring() {
- }
-
- /**
- * Do-nothing version of emitRecord
- */
- protected void emitRecord(String contextName, String recordName,
- OutputRecord outRec)
- {}
-
- /**
- * Do-nothing version of update
- */
- protected void update(MetricsRecordImpl record) {
- }
-
- /**
- * Do-nothing version of remove
- */
- protected void remove(MetricsRecordImpl record) {
- }
- }