diff --git a/hadoop-common-project/hadoop-common/CHANGES.txt b/hadoop-common-project/hadoop-common/CHANGES.txt index bc11432ae3b..c07d8a18d86 100644 --- a/hadoop-common-project/hadoop-common/CHANGES.txt +++ b/hadoop-common-project/hadoop-common/CHANGES.txt @@ -416,6 +416,9 @@ Release 2.4.0 - UNRELEASED HADOOP-10395. TestCallQueueManager is flaky. (Arpit Agarwal) HADOOP-10394. TestAuthenticationFilter is flaky. (Arpit Agarwal) + + HADOOP-10337 ConcurrentModificationException from + MetricsDynamicMBeanBase.createMBeanInfo() (Liang Xie via stack) BREAKDOWN OF HADOOP-10184 SUBTASKS AND RELATED JIRAS diff --git a/hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/metrics/util/MetricsRegistry.java b/hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/metrics/util/MetricsRegistry.java index 08479866407..58f1929d6e6 100644 --- a/hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/metrics/util/MetricsRegistry.java +++ b/hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/metrics/util/MetricsRegistry.java @@ -18,8 +18,7 @@ package org.apache.hadoop.metrics.util; import java.util.Collection; -import java.util.HashMap; -import java.util.Map; +import java.util.concurrent.ConcurrentHashMap; import org.apache.hadoop.classification.InterfaceAudience; @@ -32,7 +31,8 @@ import org.apache.hadoop.classification.InterfaceAudience; */ @InterfaceAudience.LimitedPrivate({"HDFS", "MapReduce"}) public class MetricsRegistry { - private Map metricsList = new HashMap(); + private ConcurrentHashMap metricsList = + new ConcurrentHashMap(); public MetricsRegistry() { } @@ -51,11 +51,11 @@ public class MetricsRegistry { * @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); + public void add(final String metricsName, final MetricsBase theMetricsObj) { + if (metricsList.putIfAbsent(metricsName, theMetricsObj) != null) { + throw new IllegalArgumentException("Duplicate metricsName:" + + metricsName); } - metricsList.put(metricsName, theMetricsObj); } @@ -65,7 +65,7 @@ public class MetricsRegistry { * @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) { + public MetricsBase get(final String metricsName) { return metricsList.get(metricsName); } @@ -74,7 +74,7 @@ public class MetricsRegistry { * * @return the list of metrics names */ - public synchronized Collection getKeyList() { + public Collection getKeyList() { return metricsList.keySet(); } @@ -82,7 +82,7 @@ public class MetricsRegistry { * * @return the list of metrics */ - public synchronized Collection getMetricsList() { + public Collection getMetricsList() { return metricsList.values(); } }