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Posted to common-commits@hadoop.apache.org by om...@apache.org on 2011/03/15 17:23:20 UTC
svn commit: r1081836 [3/3] - in
/hadoop/common/branches/branch-0.20-security: ./
src/core/org/apache/hadoop/classification/ src/core/org/apache/hadoop/log/
src/core/org/apache/hadoop/log/metrics/ src/core/org/apache/hadoop/metrics/
src/core/org/apache/...
Added: hadoop/common/branches/branch-0.20-security/src/core/org/apache/hadoop/metrics/util/MetricsLongValue.java
URL: http://svn.apache.org/viewvc/hadoop/common/branches/branch-0.20-security/src/core/org/apache/hadoop/metrics/util/MetricsLongValue.java?rev=1081836&view=auto
==============================================================================
--- hadoop/common/branches/branch-0.20-security/src/core/org/apache/hadoop/metrics/util/MetricsLongValue.java (added)
+++ hadoop/common/branches/branch-0.20-security/src/core/org/apache/hadoop/metrics/util/MetricsLongValue.java Tue Mar 15 16:23:19 2011
@@ -0,0 +1,92 @@
+/**
+ * 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.util;
+
+import org.apache.hadoop.classification.InterfaceAudience;
+import org.apache.hadoop.metrics.MetricsRecord;
+
+
+/**
+ * The MetricsLongValue class is for a metric that is not time varied
+ * but changes only when it is set.
+ * Each time its value is set, it is published only *once* at the next update
+ * call.
+ *
+ * @deprecated in favor of <code>org.apache.hadoop.metrics2</code> usage.
+ */
+@Deprecated
+@InterfaceAudience.LimitedPrivate({"HDFS", "MapReduce"})
+public class MetricsLongValue extends MetricsBase{
+ private long value;
+ private boolean changed;
+
+ /**
+ * Constructor - create a new metric
+ * @param nam the name of the metrics to be used to publish the metric
+ * @param registry - where the metrics object will be registered
+ */
+ public MetricsLongValue(final String nam, final MetricsRegistry registry, final String description) {
+ super(nam, description);
+ value = 0;
+ changed = false;
+ registry.add(nam, this);
+ }
+
+ /**
+ * Constructor - create a new metric
+ * @param nam the name of the metrics to be used to publish the metric
+ * @param registry - where the metrics object will be registered
+ * A description of {@link #NO_DESCRIPTION} is used
+ */
+ public MetricsLongValue(final String nam, MetricsRegistry registry) {
+ this(nam, registry, NO_DESCRIPTION);
+ }
+
+ /**
+ * Set the value
+ * @param newValue
+ */
+ public synchronized void set(final long newValue) {
+ value = newValue;
+ changed = true;
+ }
+
+ /**
+ * Get value
+ * @return the value last set
+ */
+ public synchronized long get() {
+ return value;
+ }
+
+
+ /**
+ * Push the metric to the mr.
+ * The metric is pushed only if it was updated since last push
+ *
+ * Note this does NOT push to JMX
+ * (JMX gets the info via {@link #get()}
+ *
+ * @param mr
+ */
+ public synchronized void pushMetric(final MetricsRecord mr) {
+ if (changed)
+ mr.setMetric(getName(), value);
+ changed = false;
+ }
+}
Added: hadoop/common/branches/branch-0.20-security/src/core/org/apache/hadoop/metrics/util/MetricsRegistry.java
URL: http://svn.apache.org/viewvc/hadoop/common/branches/branch-0.20-security/src/core/org/apache/hadoop/metrics/util/MetricsRegistry.java?rev=1081836&view=auto
==============================================================================
--- hadoop/common/branches/branch-0.20-security/src/core/org/apache/hadoop/metrics/util/MetricsRegistry.java (added)
+++ hadoop/common/branches/branch-0.20-security/src/core/org/apache/hadoop/metrics/util/MetricsRegistry.java Tue Mar 15 16:23:19 2011
@@ -0,0 +1,90 @@
+/**
+ * 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.util;
+
+import java.util.Collection;
+import java.util.HashMap;
+import java.util.Map;
+
+import org.apache.hadoop.classification.InterfaceAudience;
+
+/**
+ *
+ * This is the registry for metrics.
+ * Related set of metrics should be declared in a holding class and registered
+ * in a registry for those metrics which is also stored in the the holding class.
+ *
+ * @deprecated in favor of {@link org.apache.hadoop.metrics2.lib.MetricsRegistry}.
+ */
+@Deprecated
+@InterfaceAudience.LimitedPrivate({"HDFS", "MapReduce"})
+public class MetricsRegistry {
+ private Map<String, MetricsBase> metricsList = new HashMap<String, MetricsBase>();
+
+ public MetricsRegistry() {
+ }
+
+ /**
+ *
+ * @return number of metrics in the registry
+ */
+ public int size() {
+ return metricsList.size();
+ }
+
+ /**
+ * Add a new metrics to the registry
+ * @param metricsName - the name
+ * @param theMetricsObj - the metrics
+ * @throws IllegalArgumentException if a name is already registered
+ */
+ public synchronized void add(final String metricsName, final MetricsBase theMetricsObj) {
+ if (metricsList.containsKey(metricsName)) {
+ throw new IllegalArgumentException("Duplicate metricsName:" + metricsName);
+ }
+ metricsList.put(metricsName, theMetricsObj);
+ }
+
+
+ /**
+ *
+ * @param metricsName
+ * @return the metrics if there is one registered by the supplied name.
+ * Returns null if none is registered
+ */
+ public synchronized MetricsBase get(final String metricsName) {
+ return metricsList.get(metricsName);
+ }
+
+
+ /**
+ *
+ * @return the list of metrics names
+ */
+ public synchronized Collection<String> getKeyList() {
+ return metricsList.keySet();
+ }
+
+ /**
+ *
+ * @return the list of metrics
+ */
+ public synchronized Collection<MetricsBase> getMetricsList() {
+ return metricsList.values();
+ }
+}
Added: hadoop/common/branches/branch-0.20-security/src/core/org/apache/hadoop/metrics/util/MetricsTimeVaryingInt.java
URL: http://svn.apache.org/viewvc/hadoop/common/branches/branch-0.20-security/src/core/org/apache/hadoop/metrics/util/MetricsTimeVaryingInt.java?rev=1081836&view=auto
==============================================================================
--- hadoop/common/branches/branch-0.20-security/src/core/org/apache/hadoop/metrics/util/MetricsTimeVaryingInt.java (added)
+++ hadoop/common/branches/branch-0.20-security/src/core/org/apache/hadoop/metrics/util/MetricsTimeVaryingInt.java Tue Mar 15 16:23:19 2011
@@ -0,0 +1,132 @@
+/**
+ * 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.util;
+
+import org.apache.hadoop.classification.InterfaceAudience;
+import org.apache.hadoop.metrics.MetricsRecord;
+import org.apache.hadoop.util.StringUtils;
+
+import org.apache.commons.logging.Log;
+import org.apache.commons.logging.LogFactory;
+
+/**
+ * The MetricsTimeVaryingInt class is for a metric that naturally
+ * varies over time (e.g. number of files created). The metrics is accumulated
+ * over an interval (set in the metrics config file); the metrics is
+ * published at the end of each interval and then
+ * reset to zero. Hence the counter has the value in the current interval.
+ *
+ * Note if one wants a time associated with the metric then use
+ * @see org.apache.hadoop.metrics.util.MetricsTimeVaryingRate
+ *
+ * @deprecated in favor of {@link org.apache.hadoop.metrics2.lib.MutableCounterInt}.
+ */
+@Deprecated
+@InterfaceAudience.LimitedPrivate({"HDFS", "MapReduce"})
+public class MetricsTimeVaryingInt extends MetricsBase {
+
+ private static final Log LOG =
+ LogFactory.getLog("org.apache.hadoop.metrics.util");
+
+ private int currentValue;
+ private int previousIntervalValue;
+
+
+ /**
+ * Constructor - create a new metric
+ * @param nam the name of the metrics to be used to publish the metric
+ * @param registry - where the metrics object will be registered
+ * @param description - the description
+ */
+ public MetricsTimeVaryingInt(final String nam,
+ final MetricsRegistry registry,
+ final String description) {
+ super(nam, description);
+ currentValue = 0;
+ previousIntervalValue = 0;
+ registry.add(nam, this);
+ }
+
+ /**
+ * Constructor - create a new metric
+ * @param nam the name of the metrics to be used to publish the metric
+ * @param registry - where the metrics object will be registered
+ * A description of {@link #NO_DESCRIPTION} is used
+ */
+ public MetricsTimeVaryingInt(final String nam, final MetricsRegistry registry) {
+ this(nam, registry, NO_DESCRIPTION);
+ }
+
+
+
+ /**
+ * Inc metrics for incr vlaue
+ * @param incr - number of operations
+ */
+ public synchronized void inc(final int incr) {
+ currentValue += incr;
+ }
+
+ /**
+ * Inc metrics by one
+ */
+ public synchronized void inc() {
+ currentValue++;
+ }
+
+ private synchronized void intervalHeartBeat() {
+ previousIntervalValue = currentValue;
+ currentValue = 0;
+ }
+
+ /**
+ * Push the delta metrics to the mr.
+ * The delta is since the last push/interval.
+ *
+ * Note this does NOT push to JMX
+ * (JMX gets the info via {@link #previousIntervalValue}
+ *
+ * @param mr
+ */
+ public synchronized void pushMetric(final MetricsRecord mr) {
+ intervalHeartBeat();
+ try {
+ mr.incrMetric(getName(), getPreviousIntervalValue());
+ } catch (Exception e) {
+ LOG.info("pushMetric failed for " + getName() + "\n" +
+ StringUtils.stringifyException(e));
+ }
+ }
+
+
+ /**
+ * The Value at the Previous interval
+ * @return prev interval value
+ */
+ public synchronized int getPreviousIntervalValue() {
+ return previousIntervalValue;
+ }
+
+ /**
+ * The Value at the current interval
+ * @return prev interval value
+ */
+ public synchronized int getCurrentIntervalValue() {
+ return currentValue;
+ }
+}
Added: hadoop/common/branches/branch-0.20-security/src/core/org/apache/hadoop/metrics/util/MetricsTimeVaryingLong.java
URL: http://svn.apache.org/viewvc/hadoop/common/branches/branch-0.20-security/src/core/org/apache/hadoop/metrics/util/MetricsTimeVaryingLong.java?rev=1081836&view=auto
==============================================================================
--- hadoop/common/branches/branch-0.20-security/src/core/org/apache/hadoop/metrics/util/MetricsTimeVaryingLong.java (added)
+++ hadoop/common/branches/branch-0.20-security/src/core/org/apache/hadoop/metrics/util/MetricsTimeVaryingLong.java Tue Mar 15 16:23:19 2011
@@ -0,0 +1,128 @@
+package org.apache.hadoop.metrics.util;
+
+/**
+ * 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.
+ */
+
+import org.apache.hadoop.classification.InterfaceAudience;
+import org.apache.hadoop.metrics.MetricsRecord;
+import org.apache.hadoop.util.StringUtils;
+
+import org.apache.commons.logging.Log;
+import org.apache.commons.logging.LogFactory;
+
+/**
+ * The MetricsTimeVaryingLong class is for a metric that naturally
+ * varies over time (e.g. number of files created). The metrics is accumulated
+ * over an interval (set in the metrics config file); the metrics is
+ * published at the end of each interval and then
+ * reset to zero. Hence the counter has the value in the current interval.
+ *
+ * Note if one wants a time associated with the metric then use
+ * @see org.apache.hadoop.metrics.util.MetricsTimeVaryingRate
+ *
+ * @deprecated in favor of {@link org.apache.hadoop.metrics2.lib.MutableCounterLong}.
+ */
+@Deprecated
+@InterfaceAudience.LimitedPrivate({"HDFS", "MapReduce"})
+public class MetricsTimeVaryingLong extends MetricsBase{
+
+ private static final Log LOG =
+ LogFactory.getLog("org.apache.hadoop.metrics.util");
+
+ private long currentValue;
+ private long previousIntervalValue;
+
+ /**
+ * Constructor - create a new metric
+ * @param nam the name of the metrics to be used to publish the metric
+ * @param registry - where the metrics object will be registered
+ */
+ public MetricsTimeVaryingLong(final String nam, MetricsRegistry registry, final String description) {
+ super(nam, description);
+ currentValue = 0;
+ previousIntervalValue = 0;
+ registry.add(nam, this);
+ }
+
+
+ /**
+ * Constructor - create a new metric
+ * @param nam the name of the metrics to be used to publish the metric
+ * @param registry - where the metrics object will be registered
+ * A description of {@link #NO_DESCRIPTION} is used
+ */
+ public MetricsTimeVaryingLong(final String nam, MetricsRegistry registry) {
+ this(nam, registry, NO_DESCRIPTION);
+ }
+
+ /**
+ * Inc metrics for incr vlaue
+ * @param incr - number of operations
+ */
+ public synchronized void inc(final long incr) {
+ currentValue += incr;
+ }
+
+ /**
+ * Inc metrics by one
+ */
+ public synchronized void inc() {
+ currentValue++;
+ }
+
+ private synchronized void intervalHeartBeat() {
+ previousIntervalValue = currentValue;
+ currentValue = 0;
+ }
+
+ /**
+ * Push the delta metrics to the mr.
+ * The delta is since the last push/interval.
+ *
+ * Note this does NOT push to JMX
+ * (JMX gets the info via {@link #previousIntervalValue}
+ *
+ * @param mr
+ */
+ public synchronized void pushMetric(final MetricsRecord mr) {
+ intervalHeartBeat();
+ try {
+ mr.incrMetric(getName(), getPreviousIntervalValue());
+ } catch (Exception e) {
+ LOG.info("pushMetric failed for " + getName() + "\n" +
+ StringUtils.stringifyException(e));
+ }
+ }
+
+
+ /**
+ * The Value at the Previous interval
+ * @return prev interval value
+ */
+ public synchronized long getPreviousIntervalValue() {
+ return previousIntervalValue;
+ }
+
+ /**
+ * The Value at the current interval
+ * @return prev interval value
+ */
+ public synchronized long getCurrentIntervalValue() {
+ return currentValue;
+ }
+}
Added: hadoop/common/branches/branch-0.20-security/src/core/org/apache/hadoop/metrics/util/MetricsTimeVaryingRate.java
URL: http://svn.apache.org/viewvc/hadoop/common/branches/branch-0.20-security/src/core/org/apache/hadoop/metrics/util/MetricsTimeVaryingRate.java?rev=1081836&view=auto
==============================================================================
--- hadoop/common/branches/branch-0.20-security/src/core/org/apache/hadoop/metrics/util/MetricsTimeVaryingRate.java (added)
+++ hadoop/common/branches/branch-0.20-security/src/core/org/apache/hadoop/metrics/util/MetricsTimeVaryingRate.java Tue Mar 15 16:23:19 2011
@@ -0,0 +1,200 @@
+/**
+ * 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.util;
+
+import org.apache.hadoop.classification.InterfaceAudience;
+import org.apache.hadoop.metrics.MetricsRecord;
+import org.apache.hadoop.util.StringUtils;
+
+import org.apache.commons.logging.Log;
+import org.apache.commons.logging.LogFactory;
+
+/**
+ * The MetricsTimeVaryingRate class is for a rate based metric that
+ * naturally varies over time (e.g. time taken to create a file).
+ * The rate is averaged at each interval heart beat (the interval
+ * is set in the metrics config file).
+ * This class also keeps track of the min and max rates along with
+ * a method to reset the min-max.
+ *
+ * @deprecated in favor of {@link org.apache.hadoop.metrics2.lib.MutableRate}.
+ */
+@Deprecated
+@InterfaceAudience.LimitedPrivate({"HDFS", "MapReduce"})
+public class MetricsTimeVaryingRate extends MetricsBase {
+
+ private static final Log LOG =
+ LogFactory.getLog("org.apache.hadoop.metrics.util");
+
+ static class Metrics {
+ int numOperations = 0;
+ long time = 0; // total time or average time
+
+ void set(final Metrics resetTo) {
+ numOperations = resetTo.numOperations;
+ time = resetTo.time;
+ }
+
+ void reset() {
+ numOperations = 0;
+ time = 0;
+ }
+ }
+
+ static class MinMax {
+ long minTime = -1;
+ long maxTime = 0;
+
+ void set(final MinMax newVal) {
+ minTime = newVal.minTime;
+ maxTime = newVal.maxTime;
+ }
+
+ void reset() {
+ minTime = -1;
+ maxTime = 0;
+ }
+ void update(final long time) { // update min max
+ minTime = (minTime == -1) ? time : Math.min(minTime, time);
+ minTime = Math.min(minTime, time);
+ maxTime = Math.max(maxTime, time);
+ }
+ }
+ private Metrics currentData;
+ private Metrics previousIntervalData;
+ private MinMax minMax;
+
+
+ /**
+ * Constructor - create a new metric
+ * @param nam the name of the metrics to be used to publish the metric
+ * @param registry - where the metrics object will be registered
+ */
+ public MetricsTimeVaryingRate(final String nam, final MetricsRegistry registry, final String description) {
+ super(nam, description);
+ currentData = new Metrics();
+ previousIntervalData = new Metrics();
+ minMax = new MinMax();
+ registry.add(nam, this);
+ }
+
+ /**
+ * Constructor - create a new metric
+ * @param nam the name of the metrics to be used to publish the metric
+ * @param registry - where the metrics object will be registered
+ * A description of {@link #NO_DESCRIPTION} is used
+ */
+ public MetricsTimeVaryingRate(final String nam, MetricsRegistry registry) {
+ this(nam, registry, NO_DESCRIPTION);
+
+ }
+
+
+ /**
+ * Increment the metrics for numOps operations
+ * @param numOps - number of operations
+ * @param time - time for numOps operations
+ */
+ public synchronized void inc(final int numOps, final long time) {
+ currentData.numOperations += numOps;
+ currentData.time += time;
+ long timePerOps = time/numOps;
+ minMax.update(timePerOps);
+ }
+
+ /**
+ * Increment the metrics for one operation
+ * @param time for one operation
+ */
+ public synchronized void inc(final long time) {
+ currentData.numOperations++;
+ currentData.time += time;
+ minMax.update(time);
+ }
+
+
+
+ private synchronized void intervalHeartBeat() {
+ previousIntervalData.numOperations = currentData.numOperations;
+ previousIntervalData.time = (currentData.numOperations == 0) ?
+ 0 : currentData.time / currentData.numOperations;
+ currentData.reset();
+ }
+
+ /**
+ * Push the delta metrics to the mr.
+ * The delta is since the last push/interval.
+ *
+ * Note this does NOT push to JMX
+ * (JMX gets the info via {@link #getPreviousIntervalAverageTime()} and
+ * {@link #getPreviousIntervalNumOps()}
+ *
+ * @param mr
+ */
+ public synchronized void pushMetric(final MetricsRecord mr) {
+ intervalHeartBeat();
+ try {
+ mr.incrMetric(getName() + "_num_ops", getPreviousIntervalNumOps());
+ mr.setMetric(getName() + "_avg_time", getPreviousIntervalAverageTime());
+ } catch (Exception e) {
+ LOG.info("pushMetric failed for " + getName() + "\n" +
+ StringUtils.stringifyException(e));
+ }
+ }
+
+ /**
+ * The number of operations in the previous interval
+ * @return - ops in prev interval
+ */
+ public synchronized int getPreviousIntervalNumOps() {
+ return previousIntervalData.numOperations;
+ }
+
+ /**
+ * The average rate of an operation in the previous interval
+ * @return - the average rate.
+ */
+ public synchronized long getPreviousIntervalAverageTime() {
+ return previousIntervalData.time;
+ }
+
+ /**
+ * The min time for a single operation since the last reset
+ * {@link #resetMinMax()}
+ * @return min time for an operation
+ */
+ public synchronized long getMinTime() {
+ return minMax.minTime;
+ }
+
+ /**
+ * The max time for a single operation since the last reset
+ * {@link #resetMinMax()}
+ * @return max time for an operation
+ */
+ public synchronized long getMaxTime() {
+ return minMax.maxTime;
+ }
+
+ /**
+ * Reset the min max values
+ */
+ public synchronized void resetMinMax() {
+ minMax.reset();
+ }
+}
Added: hadoop/common/branches/branch-0.20-security/src/core/org/apache/hadoop/metrics/util/package-info.java
URL: http://svn.apache.org/viewvc/hadoop/common/branches/branch-0.20-security/src/core/org/apache/hadoop/metrics/util/package-info.java?rev=1081836&view=auto
==============================================================================
--- hadoop/common/branches/branch-0.20-security/src/core/org/apache/hadoop/metrics/util/package-info.java (added)
+++ hadoop/common/branches/branch-0.20-security/src/core/org/apache/hadoop/metrics/util/package-info.java Tue Mar 15 16:23:19 2011
@@ -0,0 +1,22 @@
+/*
+ * 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.
+ */
+@InterfaceAudience.LimitedPrivate({"HBase", "HDFS", "MapReduce"})
+@InterfaceStability.Evolving
+package org.apache.hadoop.metrics.util;
+import org.apache.hadoop.classification.InterfaceAudience;
+import org.apache.hadoop.classification.InterfaceStability;