diff --git a/hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/fs/DFCachingGetSpaceUsed.java b/hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/fs/DFCachingGetSpaceUsed.java
new file mode 100644
index 00000000000..6e8cd461eea
--- /dev/null
+++ b/hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/fs/DFCachingGetSpaceUsed.java
@@ -0,0 +1,48 @@
+/**
+ * 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.fs;
+
+import org.apache.hadoop.classification.InterfaceAudience;
+import org.apache.hadoop.classification.InterfaceStability;
+
+import java.io.IOException;
+
+/**
+ * Fast but inaccurate class to tell how much space HDFS is using.
+ * This class makes the assumption that the entire mount is used for
+ * HDFS and that no two hdfs data dirs are on the same disk.
+ *
+ * To use set fs.getspaceused.classname
+ * to org.apache.hadoop.fs.DFCachingGetSpaceUsed in your core-site.xml
+ *
+ */
+@InterfaceAudience.LimitedPrivate({"HDFS", "MapReduce"})
+@InterfaceStability.Evolving
+public class DFCachingGetSpaceUsed extends CachingGetSpaceUsed {
+ private final DF df;
+
+ public DFCachingGetSpaceUsed(Builder builder) throws IOException {
+ super(builder);
+ this.df = new DF(builder.getPath(), builder.getInterval());
+ }
+
+ @Override
+ protected void refresh() {
+ this.used.set(df.getUsed());
+ }
+}
diff --git a/hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/fs/DU.java b/hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/fs/DU.java
index 20e8202ea2e..b64a19d3cf0 100644
--- a/hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/fs/DU.java
+++ b/hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/fs/DU.java
@@ -31,12 +31,13 @@
@InterfaceAudience.LimitedPrivate({"HDFS", "MapReduce"})
@InterfaceStability.Evolving
public class DU extends CachingGetSpaceUsed {
- private DUShell duShell;
+ private final DUShell duShell;
@VisibleForTesting
- public DU(File path, long interval, long jitter, long initialUsed)
+ public DU(File path, long interval, long jitter, long initialUsed)
throws IOException {
super(path, interval, jitter, initialUsed);
+ this.duShell = new DUShell();
}
public DU(CachingGetSpaceUsed.Builder builder) throws IOException {
@@ -48,9 +49,6 @@ public DU(CachingGetSpaceUsed.Builder builder) throws IOException {
@Override
protected synchronized void refresh() {
- if (duShell == null) {
- duShell = new DUShell();
- }
try {
duShell.startRefresh();
} catch (IOException ioe) {
diff --git a/hadoop-common-project/hadoop-common/src/test/java/org/apache/hadoop/fs/TestDFCachingGetSpaceUsed.java b/hadoop-common-project/hadoop-common/src/test/java/org/apache/hadoop/fs/TestDFCachingGetSpaceUsed.java
new file mode 100644
index 00000000000..3def5d53880
--- /dev/null
+++ b/hadoop-common-project/hadoop-common/src/test/java/org/apache/hadoop/fs/TestDFCachingGetSpaceUsed.java
@@ -0,0 +1,75 @@
+/**
+ * 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.fs;
+
+import org.apache.commons.lang.RandomStringUtils;
+import org.apache.hadoop.test.GenericTestUtils;
+import org.junit.After;
+import org.junit.Before;
+import org.junit.Test;
+
+import java.io.File;
+import java.io.IOException;
+import java.io.RandomAccessFile;
+
+
+import static org.junit.Assert.assertTrue;
+
+/**
+ * Test to make sure df can run and work.
+ */
+public class TestDFCachingGetSpaceUsed {
+ final static private File DF_DIR = GenericTestUtils.getTestDir("testdfspace");
+ public static final int FILE_SIZE = 1024;
+
+ @Before
+ public void setUp() {
+ FileUtil.fullyDelete(DF_DIR);
+ assertTrue(DF_DIR.mkdirs());
+ }
+
+ @After
+ public void tearDown() throws IOException {
+ FileUtil.fullyDelete(DF_DIR);
+ }
+
+ @Test
+ public void testCanBuildRun() throws Exception {
+ File file = writeFile("testCanBuild");
+
+ GetSpaceUsed instance = new CachingGetSpaceUsed.Builder()
+ .setPath(file)
+ .setInterval(50060)
+ .setKlass(DFCachingGetSpaceUsed.class)
+ .build();
+ assertTrue(instance instanceof DFCachingGetSpaceUsed);
+ assertTrue(instance.getUsed() >= FILE_SIZE - 20);
+ ((DFCachingGetSpaceUsed) instance).close();
+ }
+
+ private File writeFile(String fileName) throws IOException {
+ File f = new File(DF_DIR, fileName);
+ assertTrue(f.createNewFile());
+ RandomAccessFile randomAccessFile = new RandomAccessFile(f, "rws");
+ randomAccessFile.writeUTF(RandomStringUtils.randomAlphabetic(FILE_SIZE));
+ randomAccessFile.getFD().sync();
+ randomAccessFile.close();
+ return f;
+ }
+
+}
\ No newline at end of file