commit bc66a0dcd8233b7ead17dd0087bcdac58c32feb3

Author: Jitendra Nath Pandey <jitendra@sufferhome-lm.(none)>
Date:   Tue Feb 1 16:40:24 2011 -0800

    HADOOP-6432. Add Statistics support in FileContext.
                 from https://issues.apache.org/jira/secure/attachment/12469995/HADOOP-6432-trunk.8.patch


git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/yahoo-merge@1079165 13f79535-47bb-0310-9956-ffa450edef68

src/test/core/org/apache/hadoop/fs/FCStatisticsBaseTest.java

@@ -0,0 +1,100 @@
+/**
+ * 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 java.io.IOException;
+import java.net.URI;
+import java.net.URISyntaxException;
+import java.util.Map;
+
+import org.apache.hadoop.fs.FileSystem.Statistics;
+import org.junit.Assert;
+import org.junit.Test;
+
+import static org.apache.hadoop.fs.FileContextTestHelper.*;
+
+/**
+ * <p>
+ *   Base class to test {@link FileContext} Statistics.
+ * </p>
+ */
+public abstract class FCStatisticsBaseTest {
+  
+  static protected int blockSize = 512;
+  static protected int numBlocks = 1;
+  
+  //fc should be set appropriately by the deriving test.
+  protected static FileContext fc = null;
+  
+  @Test
+  public void testStatistics() throws IOException, URISyntaxException {
+    URI fsUri = getFsUri();
+    Statistics stats = FileContext.getStatistics(fsUri);
+    Assert.assertEquals(0, stats.getBytesRead());
+    Path filePath = getTestRootPath(fc, "file1");
+    createFile(fc, filePath, numBlocks, blockSize);
+
+    Assert.assertEquals(0, stats.getBytesRead());
+    verifyWrittenBytes(stats);
+    FSDataInputStream fstr = fc.open(filePath);
+    byte[] buf = new byte[blockSize];
+    int bytesRead = fstr.read(buf, 0, blockSize);
+    Assert.assertEquals(blockSize, bytesRead);
+    verifyReadBytes(stats);
+    verifyWrittenBytes(stats);
+    verifyReadBytes(FileContext.getStatistics(getFsUri()));
+    Map<URI, Statistics> statsMap = FileContext.getAllStatistics();
+    URI exactUri = getSchemeAuthorityUri();
+    verifyWrittenBytes(statsMap.get(exactUri));
+    fc.delete(filePath, true);
+  }
+
+  /**
+   * Bytes read may be different for different file systems. This method should
+   * throw assertion error if bytes read are incorrect.
+   * 
+   * @param stats
+   */
+  protected abstract void verifyReadBytes(Statistics stats);
+
+  /**
+   * Bytes written may be different for different file systems. This method should
+   * throw assertion error if bytes written are incorrect.
+   * 
+   * @param stats
+   */
+  protected abstract void verifyWrittenBytes(Statistics stats);
+  
+  /**
+   * Returns the filesystem uri. Should be set
+   * @return URI
+   */
+  protected abstract URI getFsUri();
+
+  protected URI getSchemeAuthorityUri() {
+    URI uri = getFsUri();
+    String SchemeAuthString = uri.getScheme() + "://";
+    if (uri.getAuthority() == null) {
+      SchemeAuthString += "/";
+    } else {
+      SchemeAuthString += uri.getAuthority();
+    }
+    return URI.create(SchemeAuthString);
+  }
+}

src/test/core/org/apache/hadoop/fs/TestLocalFsFCStatistics.java

@@ -0,0 +1,63 @@
+/**
+ * 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 java.net.URI;
+
+import org.apache.hadoop.fs.FileSystem.Statistics;
+import org.junit.After;
+import org.junit.Assert;
+import org.junit.Before;
+
+import static org.apache.hadoop.fs.FileContextTestHelper.*;
+
+/**
+ * <p>
+ *    Tests the File Context Statistics for {@link LocalFileSystem}
+ * </p>
+ */
+public class TestLocalFsFCStatistics extends FCStatisticsBaseTest {
+  
+  static final String LOCAL_FS_ROOT_URI =  "file:///tmp/test";
+
+  @Before
+  public void setUp() throws Exception {
+    fc = FileContext.getLocalFSFileContext();
+    fc.mkdir(getTestRootPath(fc, "test"), FileContext.DEFAULT_PERM, true);
+  }
+
+  @After
+  public void tearDown() throws Exception {
+    fc.delete(getTestRootPath(fc, "test"), true);
+  }
+
+  protected void verifyReadBytes(Statistics stats) {
+    Assert.assertEquals(blockSize, stats.getBytesRead());
+  }
+
+  protected void verifyWrittenBytes(Statistics stats) {
+    //Extra 12 bytes are written apart from the block.
+    Assert.assertEquals(blockSize + 12, stats.getBytesWritten());
+  }
+  
+  protected URI getFsUri() {
+    return URI.create(LOCAL_FS_ROOT_URI);
+  }
+
+}