Author: cmccabe
Date: Thu Aug 22 23:37:51 2013
New Revision: 1516669
URL: http://svn.apache.org/r1516669
Log:
HDFS-5052. Add cacheRequest/uncacheRequest support to NameNode. (Contributed
by Colin Patrick McCabe.)
Added:
hadoop/common/branches/HDFS-4949/hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/util/Fallible.java
Added:
hadoop/common/branches/HDFS-4949/hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/util/Fallible.java
URL:
http://svn.apache.org/viewvc/hadoop/common/branches/HDFS-4949/hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/util/Fallible.java?rev=1516669&view=auto
==============================================================================
---
hadoop/common/branches/HDFS-4949/hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/util/Fallible.java
(added)
+++
hadoop/common/branches/HDFS-4949/hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/util/Fallible.java
Thu Aug 22 23:37:51 2013
@@ -0,0 +1,53 @@
+/**
+ * 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.util;
+
+import java.io.IOException;
+
+import org.apache.hadoop.classification.InterfaceAudience;
+import org.apache.hadoop.classification.InterfaceStability;
+
+/**
+ * Contains either a value of type T, or an IOException.
+ *
+ * This can be useful as a return value for batch APIs that need granular
+ * error reporting.
+ */
+@InterfaceAudience.LimitedPrivate({"HDFS"})
+@InterfaceStability.Unstable
+public class Fallible<T> {
+ private final T val;
+ private final IOException ioe;
+
+ public Fallible(T val) {
+ this.val = val;
+ this.ioe = null;
+ }
+
+ public Fallible(IOException ioe) {
+ this.val = null;
+ this.ioe = ioe;
+ }
+
+ public T get() throws IOException {
+ if (ioe != null) {
+ throw new IOException(ioe);
+ }
+ return this.val;
+ }
+}
