HDFS-10556. DistCpOptions should be validated automatically. Contributed by Mingliang Liu.

hadoop-tools/hadoop-distcp/src/main/java/org/apache/hadoop/tools/DistCpOptions.java

@@ -163,6 +163,7 @@ public class DistCpOptions {
    * @param atomicCommit - boolean switch
    */
   public void setAtomicCommit(boolean atomicCommit) {
+    validate(DistCpOptionSwitch.ATOMIC_COMMIT, atomicCommit);
     this.atomicCommit = atomicCommit;
   }
 
@@ -181,6 +182,7 @@ public class DistCpOptions {
    * @param syncFolder - boolean switch
    */
   public void setSyncFolder(boolean syncFolder) {
+    validate(DistCpOptionSwitch.SYNC_FOLDERS, syncFolder);
     this.syncFolder = syncFolder;
   }
 
@@ -199,7 +201,22 @@ public class DistCpOptions {
    * @param deleteMissing - boolean switch
    */
   public void setDeleteMissing(boolean deleteMissing) {
+    validate(DistCpOptionSwitch.DELETE_MISSING, deleteMissing);
     this.deleteMissing = deleteMissing;
+    ignoreDeleteMissingIfUseDiff();
+  }
+
+  /**
+   * -delete and -diff are mutually exclusive.
+   * For backward compatibility, we ignore the -delete option here, instead of
+   * throwing an IllegalArgumentException. See HDFS-10397 for more discussion.
+   */
+  private void ignoreDeleteMissingIfUseDiff() {
+    if (deleteMissing && useDiff) {
+      OptionsParser.LOG.warn("-delete and -diff are mutually exclusive. " +
+          "The -delete option will be ignored.");
+      deleteMissing = false;
+    }
   }
 
   /**
@@ -254,6 +271,7 @@ public class DistCpOptions {
    * @param overwrite - boolean switch
    */
   public void setOverwrite(boolean overwrite) {
+    validate(DistCpOptionSwitch.OVERWRITE, overwrite);
     this.overwrite = overwrite;
   }
 
@@ -269,6 +287,7 @@ public class DistCpOptions {
    * update option and CRC is not skipped.
    */
   public void setAppend(boolean append) {
+    validate(DistCpOptionSwitch.APPEND, append);
     this.append = append;
   }
 
@@ -285,9 +304,11 @@ public class DistCpOptions {
   }
 
   public void setUseDiff(boolean useDiff, String fromSnapshot, String toSnapshot) {
+    validate(DistCpOptionSwitch.DIFF, useDiff);
     this.useDiff = useDiff;
     this.fromSnapshot = fromSnapshot;
     this.toSnapshot = toSnapshot;
+    ignoreDeleteMissingIfUseDiff();
   }
 
   public void disableUsingDiff() {
@@ -311,6 +332,7 @@ public class DistCpOptions {
    * @param skipCRC - boolean switch
    */
   public void setSkipCRC(boolean skipCRC) {
+    validate(DistCpOptionSwitch.SKIP_CRC, skipCRC);
     this.skipCRC = skipCRC;
   }
 
@@ -565,15 +587,20 @@ public class DistCpOptions {
     this.filtersFile = filtersFilename;
   }
 
-  void validate() {
+  public void validate(DistCpOptionSwitch option, boolean value) {
-    if (useDiff && deleteMissing) {
+
-      // -delete and -diff are mutually exclusive. For backward compatibility,
+    boolean syncFolder = (option == DistCpOptionSwitch.SYNC_FOLDERS ?
-      // we ignore the -delete option here, instead of throwing an
+        value : this.syncFolder);
-      // IllegalArgumentException. See HDFS-10397 for more discussion.
+    boolean overwrite = (option == DistCpOptionSwitch.OVERWRITE ?
-      OptionsParser.LOG.warn("-delete and -diff are mutually exclusive. " +
+        value : this.overwrite);
-          "The -delete option will be ignored.");
+    boolean deleteMissing = (option == DistCpOptionSwitch.DELETE_MISSING ?
-      setDeleteMissing(false);
+        value : this.deleteMissing);
-    }
+    boolean atomicCommit = (option == DistCpOptionSwitch.ATOMIC_COMMIT ?
+        value : this.atomicCommit);
+    boolean skipCRC = (option == DistCpOptionSwitch.SKIP_CRC ?
+        value : this.skipCRC);
+    boolean append = (option == DistCpOptionSwitch.APPEND ? value : this.append);
+    boolean useDiff = (option == DistCpOptionSwitch.DIFF ? value : this.useDiff);
 
     if (syncFolder && atomicCommit) {
       throw new IllegalArgumentException("Atomic commit can't be used with " +

hadoop-tools/hadoop-distcp/src/main/java/org/apache/hadoop/tools/OptionsParser.java

@@ -88,26 +88,14 @@ public class OptionsParser {
 
     DistCpOptions option = parseSourceAndTargetPaths(command);
 
-    option.setIgnoreFailures(
+    //Process all the other option switches and set options appropriately
-        command.hasOption(DistCpOptionSwitch.IGNORE_FAILURES.getSwitch()));
+    if (command.hasOption(DistCpOptionSwitch.IGNORE_FAILURES.getSwitch())) {
+      option.setIgnoreFailures(true);
+    }
 
-    option.setAtomicCommit(
+    if (command.hasOption(DistCpOptionSwitch.ATOMIC_COMMIT.getSwitch())) {
-        command.hasOption(DistCpOptionSwitch.ATOMIC_COMMIT.getSwitch()));
+      option.setAtomicCommit(true);
-
+    }
-    option.setSyncFolder(
-        command.hasOption(DistCpOptionSwitch.SYNC_FOLDERS.getSwitch()));
-
-    option.setOverwrite(
-        command.hasOption(DistCpOptionSwitch.OVERWRITE.getSwitch()));
-
-    option.setAppend(
-        command.hasOption(DistCpOptionSwitch.APPEND.getSwitch()));
-
-    option.setDeleteMissing(
-        command.hasOption(DistCpOptionSwitch.DELETE_MISSING.getSwitch()));
-
-    option.setSkipCRC(
-        command.hasOption(DistCpOptionSwitch.SKIP_CRC.getSwitch()));
 
     if (command.hasOption(DistCpOptionSwitch.WORK_PATH.getSwitch()) &&
         option.shouldAtomicCommit()) {
@@ -123,6 +111,25 @@ public class OptionsParser {
       option.setLogPath(new Path(getVal(command, DistCpOptionSwitch.LOG_PATH.getSwitch())));
     }
 
+    if (command.hasOption(DistCpOptionSwitch.SYNC_FOLDERS.getSwitch())) {
+      option.setSyncFolder(true);
+    }
+
+    if (command.hasOption(DistCpOptionSwitch.OVERWRITE.getSwitch())) {
+      option.setOverwrite(true);
+    }
+
+    if (command.hasOption(DistCpOptionSwitch.APPEND.getSwitch())) {
+      option.setAppend(true);
+    }
+
+    if (command.hasOption(DistCpOptionSwitch.DELETE_MISSING.getSwitch())) {
+      option.setDeleteMissing(true);
+    }
+
+    if (command.hasOption(DistCpOptionSwitch.SKIP_CRC.getSwitch())) {
+      option.setSkipCRC(true);
+    }
 
     if (command.hasOption(DistCpOptionSwitch.BLOCKING.getSwitch())) {
       option.setBlocking(false);
@@ -162,8 +169,6 @@ public class OptionsParser {
           DistCpOptionSwitch.FILTERS.getSwitch()));
     }
 
-    option.validate();
-
     return option;
   }
 

hadoop-tools/hadoop-distcp/src/test/java/org/apache/hadoop/tools/TestDistCpOptions.java

@@ -0,0 +1,510 @@
+/**
+ * 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.tools;
+
+import org.apache.hadoop.fs.Path;
+import org.apache.hadoop.tools.DistCpOptions.FileAttribute;
+
+import org.junit.Assert;
+import org.junit.Test;
+
+import java.util.Collections;
+
+import static org.apache.hadoop.test.GenericTestUtils.assertExceptionContains;
+import static org.apache.hadoop.tools.DistCpOptions.maxNumListstatusThreads;
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.fail;
+
+/**
+ * This is to test constructing {@link DistCpOptions} manually with setters.
+ *
+ * The test cases in this class is very similar to the parser test, see
+ * {@link TestOptionsParser}.
+ */
+public class TestDistCpOptions {
+
+  @Test
+  public void testSetIgnoreFailure() {
+    final DistCpOptions options = new DistCpOptions(
+        Collections.singletonList(new Path("hdfs://localhost:8020/source")),
+        new Path("hdfs://localhost:8020/target/"));
+    Assert.assertFalse(options.shouldIgnoreFailures());
+
+    options.setIgnoreFailures(true);
+    Assert.assertTrue(options.shouldIgnoreFailures());
+  }
+
+  @Test
+  public void testSetOverwrite() {
+    final DistCpOptions options = new DistCpOptions(
+        Collections.singletonList(new Path("hdfs://localhost:8020/source")),
+        new Path("hdfs://localhost:8020/target/"));
+    Assert.assertFalse(options.shouldOverwrite());
+
+    options.setOverwrite(true);
+    Assert.assertTrue(options.shouldOverwrite());
+
+    try {
+      options.setSyncFolder(true);
+      Assert.fail("Update and overwrite aren't allowed together");
+    } catch (IllegalArgumentException ignore) {
+    }
+  }
+
+  @Test
+  public void testLogPath() {
+    final DistCpOptions options = new DistCpOptions(
+        Collections.singletonList(new Path("hdfs://localhost:8020/source")),
+        new Path("hdfs://localhost:8020/target/"));
+    Assert.assertNull(options.getLogPath());
+
+    final Path logPath = new Path("hdfs://localhost:8020/logs");
+    options.setLogPath(logPath);
+    Assert.assertEquals(logPath, options.getLogPath());
+  }
+
+  @Test
+  public void testSetBlokcing() {
+    final DistCpOptions options = new DistCpOptions(
+        Collections.singletonList(new Path("hdfs://localhost:8020/source")),
+        new Path("hdfs://localhost:8020/target/"));
+    Assert.assertTrue(options.shouldBlock());
+
+    options.setBlocking(false);
+    Assert.assertFalse(options.shouldBlock());
+  }
+
+  @Test
+  public void testSetBandwidth() {
+    final DistCpOptions options = new DistCpOptions(
+        Collections.singletonList(new Path("hdfs://localhost:8020/source")),
+        new Path("hdfs://localhost:8020/target/"));
+    Assert.assertEquals(DistCpConstants.DEFAULT_BANDWIDTH_MB,
+        options.getMapBandwidth());
+
+    options.setMapBandwidth(11);
+    Assert.assertEquals(11, options.getMapBandwidth());
+  }
+
+  @Test(expected = AssertionError.class)
+  public void testSetNonPositiveBandwidth() {
+    final DistCpOptions options = new DistCpOptions(
+        Collections.singletonList(new Path("hdfs://localhost:8020/source")),
+        new Path("hdfs://localhost:8020/target/"));
+    options.setMapBandwidth(-11);
+  }
+
+  @Test(expected = AssertionError.class)
+  public void testSetZeroBandwidth() {
+    final DistCpOptions options = new DistCpOptions(
+        Collections.singletonList(new Path("hdfs://localhost:8020/source")),
+        new Path("hdfs://localhost:8020/target/"));
+    options.setMapBandwidth(0);
+  }
+
+  @Test
+  public void testSetSkipCRC() {
+    final DistCpOptions options = new DistCpOptions(
+        Collections.singletonList(new Path("hdfs://localhost:8020/source")),
+        new Path("hdfs://localhost:8020/target/"));
+    Assert.assertFalse(options.shouldSkipCRC());
+
+    options.setSyncFolder(true);
+    options.setSkipCRC(true);
+    Assert.assertTrue(options.shouldSyncFolder());
+    Assert.assertTrue(options.shouldSkipCRC());
+  }
+
+  @Test
+  public void testSetAtomicCommit() {
+    final DistCpOptions options = new DistCpOptions(
+        Collections.singletonList(new Path("hdfs://localhost:8020/source")),
+        new Path("hdfs://localhost:8020/target/"));
+    Assert.assertFalse(options.shouldAtomicCommit());
+
+    options.setAtomicCommit(true);
+    Assert.assertTrue(options.shouldAtomicCommit());
+
+    try {
+      options.setSyncFolder(true);
+      Assert.fail("Atomic and sync folders were mutually exclusive");
+    } catch (IllegalArgumentException ignore) {
+    }
+  }
+
+  @Test
+  public void testSetWorkPath() {
+    final DistCpOptions options = new DistCpOptions(
+        Collections.singletonList(new Path("hdfs://localhost:8020/source")),
+        new Path("hdfs://localhost:8020/target/"));
+    Assert.assertNull(options.getAtomicWorkPath());
+
+    options.setAtomicCommit(true);
+    Assert.assertNull(options.getAtomicWorkPath());
+
+    final Path workPath = new Path("hdfs://localhost:8020/work");
+    options.setAtomicWorkPath(workPath);
+    Assert.assertEquals(workPath,
+        options.getAtomicWorkPath());
+  }
+
+  @Test
+  public void testSetSyncFolders() {
+    final DistCpOptions options = new DistCpOptions(
+        Collections.singletonList(new Path("hdfs://localhost:8020/source")),
+        new Path("hdfs://localhost:8020/target/"));
+    Assert.assertFalse(options.shouldSyncFolder());
+
+    options.setSyncFolder(true);
+    Assert.assertTrue(options.shouldSyncFolder());
+  }
+
+  @Test
+  public void testSetDeleteMissing() {
+    {
+      final DistCpOptions options = new DistCpOptions(
+          Collections.singletonList(new Path("hdfs://localhost:8020/source")),
+          new Path("hdfs://localhost:8020/target/"));
+      Assert.assertFalse(options.shouldDeleteMissing());
+
+      options.setSyncFolder(true);
+      options.setDeleteMissing(true);
+      Assert.assertTrue(options.shouldSyncFolder());
+      Assert.assertTrue(options.shouldDeleteMissing());
+    }
+    {
+      final DistCpOptions options = new DistCpOptions(
+          Collections.singletonList(new Path("hdfs://localhost:8020/source")),
+          new Path("hdfs://localhost:8020/target/"));
+      options.setOverwrite(true);
+      options.setDeleteMissing(true);
+      Assert.assertTrue(options.shouldOverwrite());
+      Assert.assertTrue(options.shouldDeleteMissing());
+    }
+    try {
+      final DistCpOptions options = new DistCpOptions(
+          Collections.singletonList(new Path("hdfs://localhost:8020/source")),
+          new Path("hdfs://localhost:8020/target/"));
+      options.setDeleteMissing(true);
+      fail("Delete missing should fail without update or overwrite options");
+    } catch (IllegalArgumentException e) {
+      assertExceptionContains("Delete missing is applicable only with update " +
+          "or overwrite options", e);
+    }
+    try {
+      final DistCpOptions options = new DistCpOptions(
+          new Path("hdfs://localhost:8020/source/first"),
+          new Path("hdfs://localhost:8020/target/"));
+      options.setSyncFolder(true);
+      options.setDeleteMissing(true);
+      options.setUseDiff(true, "s1", "s2");
+      assertFalse("-delete should be ignored when -diff is specified",
+          options.shouldDeleteMissing());
+    } catch (IllegalArgumentException e) {
+      fail("Got unexpected IllegalArgumentException: " + e.getMessage());
+    }
+  }
+
+  @Test
+  public void testSetSSLConf() {
+    final DistCpOptions options = new DistCpOptions(
+        Collections.singletonList(new Path("hdfs://localhost:8020/source")),
+        new Path("hdfs://localhost:8020/target/"));
+    Assert.assertNull(options.getSslConfigurationFile());
+
+    options.setSslConfigurationFile("/tmp/ssl-client.xml");
+    Assert.assertEquals("/tmp/ssl-client.xml",
+        options.getSslConfigurationFile());
+  }
+
+  @Test
+  public void testSetMaps() {
+    {
+      final DistCpOptions options = new DistCpOptions(
+          Collections.singletonList(new Path("hdfs://localhost:8020/source")),
+          new Path("hdfs://localhost:8020/target/"));
+      Assert.assertEquals(DistCpConstants.DEFAULT_MAPS, options.getMaxMaps());
+
+      options.setMaxMaps(1);
+      Assert.assertEquals(1, options.getMaxMaps());
+    }
+    {
+      final DistCpOptions options = new DistCpOptions(
+          Collections.singletonList(new Path("hdfs://localhost:8020/source")),
+          new Path("hdfs://localhost:8020/target/"));
+      options.setMaxMaps(0);
+      Assert.assertEquals(1, options.getMaxMaps());
+    }
+  }
+
+  @Test
+  public void testSetNumListtatusThreads() {
+    {
+      final DistCpOptions options = new DistCpOptions(
+          Collections.singletonList(new Path("hdfs://localhost:8020/source")),
+          new Path("hdfs://localhost:8020/target/"));
+      // If command line argument isn't set, we expect .getNumListstatusThreads
+      // option to be zero (so that we know when to override conf properties).
+      Assert.assertEquals(0, options.getNumListstatusThreads());
+
+      options.setNumListstatusThreads(12);
+      Assert.assertEquals(12, options.getNumListstatusThreads());
+    }
+
+    {
+      final DistCpOptions options = new DistCpOptions(
+          Collections.singletonList(new Path("hdfs://localhost:8020/source")),
+          new Path("hdfs://localhost:8020/target/"));
+      options.setNumListstatusThreads(0);
+      Assert.assertEquals(0, options.getNumListstatusThreads());
+    }
+
+    // Ignore large number of threads.
+    {
+      final DistCpOptions options = new DistCpOptions(
+          Collections.singletonList(new Path("hdfs://localhost:8020/source")),
+          new Path("hdfs://localhost:8020/target/"));
+      options.setNumListstatusThreads(maxNumListstatusThreads * 2);
+      Assert.assertEquals(maxNumListstatusThreads,
+          options.getNumListstatusThreads());
+    }
+  }
+
+  @Test
+  public void testSourceListing() {
+    final DistCpOptions options = new DistCpOptions(
+        new Path("hdfs://localhost:8020/source/first"),
+        new Path("hdfs://localhost:8020/target/"));
+    Assert.assertEquals(new Path("hdfs://localhost:8020/source/first"),
+        options.getSourceFileListing());
+  }
+
+  @Test(expected = AssertionError.class)
+  public void testMissingTarget() {
+    new DistCpOptions(new Path("hdfs://localhost:8020/source/first"), null);
+  }
+
+  @Test
+  public void testToString() {
+    DistCpOptions option = new DistCpOptions(new Path("abc"), new Path("xyz"));
+    final String val = "DistCpOptions{atomicCommit=false, syncFolder=false, "
+        + "deleteMissing=false, ignoreFailures=false, overwrite=false, "
+        + "skipCRC=false, blocking=true, numListstatusThreads=0, maxMaps=20, "
+        + "mapBandwidth=100, sslConfigurationFile='null', "
+        + "copyStrategy='uniformsize', preserveStatus=[], "
+        + "preserveRawXattrs=false, atomicWorkPath=null, logPath=null, "
+        + "sourceFileListing=abc, sourcePaths=null, targetPath=xyz, "
+        + "targetPathExists=true, filtersFile='null'}";
+    String optionString = option.toString();
+    Assert.assertEquals(val, optionString);
+    Assert.assertNotSame(DistCpOptionSwitch.ATOMIC_COMMIT.toString(),
+        DistCpOptionSwitch.ATOMIC_COMMIT.name());
+  }
+
+  @Test
+  public void testCopyStrategy() {
+    {
+      final DistCpOptions options = new DistCpOptions(
+          new Path("hdfs://localhost:8020/source/first"),
+          new Path("hdfs://localhost:8020/target/"));
+      Assert.assertEquals(DistCpConstants.UNIFORMSIZE,
+          options.getCopyStrategy());
+      options.setCopyStrategy("dynamic");
+      Assert.assertEquals("dynamic", options.getCopyStrategy());
+    }
+  }
+
+  @Test
+  public void testTargetPath() {
+    final DistCpOptions options = new DistCpOptions(
+        new Path("hdfs://localhost:8020/source/first"),
+        new Path("hdfs://localhost:8020/target/"));
+    Assert.assertEquals(new Path("hdfs://localhost:8020/target/"),
+        options.getTargetPath());
+  }
+
+  @Test
+  public void testPreserve() {
+    {
+      final DistCpOptions options = new DistCpOptions(
+          new Path("hdfs://localhost:8020/source/first"),
+          new Path("hdfs://localhost:8020/target/"));
+      Assert.assertFalse(options.shouldPreserve(FileAttribute.BLOCKSIZE));
+      Assert.assertFalse(options.shouldPreserve(FileAttribute.REPLICATION));
+      Assert.assertFalse(options.shouldPreserve(FileAttribute.PERMISSION));
+      Assert.assertFalse(options.shouldPreserve(FileAttribute.USER));
+      Assert.assertFalse(options.shouldPreserve(FileAttribute.GROUP));
+      Assert.assertFalse(options.shouldPreserve(FileAttribute.CHECKSUMTYPE));
+    }
+    {
+      final DistCpOptions options = new DistCpOptions(
+          new Path("hdfs://localhost:8020/source/first"),
+          new Path("hdfs://localhost:8020/target/"));
+      options.preserve(FileAttribute.ACL);
+      Assert.assertFalse(options.shouldPreserve(FileAttribute.BLOCKSIZE));
+      Assert.assertFalse(options.shouldPreserve(FileAttribute.REPLICATION));
+      Assert.assertFalse(options.shouldPreserve(FileAttribute.PERMISSION));
+      Assert.assertFalse(options.shouldPreserve(FileAttribute.USER));
+      Assert.assertFalse(options.shouldPreserve(FileAttribute.GROUP));
+      Assert.assertFalse(options.shouldPreserve(FileAttribute.CHECKSUMTYPE));
+      Assert.assertTrue(options.shouldPreserve(FileAttribute.ACL));
+    }
+    {
+      final DistCpOptions options = new DistCpOptions(
+          Collections.singletonList(new Path("hdfs://localhost:8020/source/")),
+          new Path("hdfs://localhost:8020/target/"));
+      options.preserve(FileAttribute.BLOCKSIZE);
+      options.preserve(FileAttribute.REPLICATION);
+      options.preserve(FileAttribute.PERMISSION);
+      options.preserve(FileAttribute.USER);
+      options.preserve(FileAttribute.GROUP);
+      options.preserve(FileAttribute.CHECKSUMTYPE);
+
+      Assert.assertTrue(options.shouldPreserve(FileAttribute.BLOCKSIZE));
+      Assert.assertTrue(options.shouldPreserve(FileAttribute.REPLICATION));
+      Assert.assertTrue(options.shouldPreserve(FileAttribute.PERMISSION));
+      Assert.assertTrue(options.shouldPreserve(FileAttribute.USER));
+      Assert.assertTrue(options.shouldPreserve(FileAttribute.GROUP));
+      Assert.assertTrue(options.shouldPreserve(FileAttribute.CHECKSUMTYPE));
+      Assert.assertFalse(options.shouldPreserve(FileAttribute.XATTR));
+    }
+  }
+
+  @Test
+  public void testAppendOption() {
+    {
+      final DistCpOptions options = new DistCpOptions(
+          Collections.singletonList(new Path("hdfs://localhost:8020/source/")),
+          new Path("hdfs://localhost:8020/target/"));
+      options.setSyncFolder(true);
+      options.setAppend(true);
+      Assert.assertTrue(options.shouldAppend());
+    }
+
+    try {
+      // make sure -append is only valid when -update is specified
+      final DistCpOptions options = new DistCpOptions(
+          Collections.singletonList(new Path("hdfs://localhost:8020/source/")),
+          new Path("hdfs://localhost:8020/target/"));
+      options.setAppend(true);
+      fail("Append should fail if update option is not specified");
+    } catch (IllegalArgumentException e) {
+      assertExceptionContains(
+          "Append is valid only with update options", e);
+    }
+
+    try {
+      // make sure -append is invalid when skipCrc is specified
+      final DistCpOptions options = new DistCpOptions(
+          Collections.singletonList(new Path("hdfs://localhost:8020/source/")),
+          new Path("hdfs://localhost:8020/target/"));
+      options.setSyncFolder(true);
+      options.setAppend(true);
+      options.setSkipCRC(true);
+      fail("Append should fail if skipCrc option is specified");
+    } catch (IllegalArgumentException e) {
+      assertExceptionContains(
+          "Append is disallowed when skipping CRC", e);
+    }
+  }
+
+  @Test
+  public void testDiffOption() {
+    {
+      final DistCpOptions options = new DistCpOptions(
+          new Path("hdfs://localhost:8020/source/first"),
+          new Path("hdfs://localhost:8020/target/"));
+      options.setSyncFolder(true);
+      options.setUseDiff(true, "s1", "s2");
+      Assert.assertTrue(options.shouldUseDiff());
+      Assert.assertEquals("s1", options.getFromSnapshot());
+      Assert.assertEquals("s2", options.getToSnapshot());
+    }
+    {
+      final DistCpOptions options = new DistCpOptions(
+          new Path("hdfs://localhost:8020/source/first"),
+          new Path("hdfs://localhost:8020/target/"));
+      options.setSyncFolder(true);
+      options.setUseDiff(true, "s1", ".");
+      Assert.assertTrue(options.shouldUseDiff());
+      Assert.assertEquals("s1", options.getFromSnapshot());
+      Assert.assertEquals(".", options.getToSnapshot());
+    }
+
+    // make sure -diff is only valid when -update is specified
+    try {
+      final DistCpOptions options = new DistCpOptions(
+          new Path("hdfs://localhost:8020/source/first"),
+          new Path("hdfs://localhost:8020/target/"));
+      options.setUseDiff(true, "s1", "s2");
+      fail("-diff should fail if -update option is not specified");
+    } catch (IllegalArgumentException e) {
+      assertExceptionContains(
+          "Diff is valid only with update options", e);
+    }
+
+    try {
+      final DistCpOptions options = new DistCpOptions(
+          new Path("hdfs://localhost:8020/source/first"),
+          new Path("hdfs://localhost:8020/target/"));
+      options.setSyncFolder(true);
+      options.setUseDiff(true, "s1", "s2");
+      options.setDeleteMissing(true);
+      assertFalse("-delete should be ignored when -diff is specified",
+          options.shouldDeleteMissing());
+    } catch (IllegalArgumentException e) {
+      fail("Got unexpected IllegalArgumentException: " + e.getMessage());
+    }
+
+    try {
+      final DistCpOptions options = new DistCpOptions(
+          new Path("hdfs://localhost:8020/source/first"),
+          new Path("hdfs://localhost:8020/target/"));
+      options.setUseDiff(true, "s1", "s2");
+      options.setDeleteMissing(true);
+      fail("-diff should fail if -update option is not specified");
+    } catch (IllegalArgumentException e) {
+      assertExceptionContains(
+          "Diff is valid only with update options", e);
+    }
+
+    try {
+      final DistCpOptions options = new DistCpOptions(
+          new Path("hdfs://localhost:8020/source/first"),
+          new Path("hdfs://localhost:8020/target/"));
+      options.setDeleteMissing(true);
+      options.setUseDiff(true, "s1", "s2");
+      fail("-delete should fail if -update option is not specified");
+    } catch (IllegalArgumentException e) {
+      assertExceptionContains("Delete missing is applicable only with update " +
+          "or overwrite options", e);
+    }
+  }
+
+  @Test
+  public void testExclusionsOption() {
+    DistCpOptions options = new DistCpOptions(
+        new Path("hdfs://localhost:8020/source/first"),
+        new Path("hdfs://localhost:8020/target/"));
+    Assert.assertNull(options.getFiltersFile());
+
+    options.setFiltersFile("/tmp/filters.txt");
+    Assert.assertEquals("/tmp/filters.txt", options.getFiltersFile());
+  }
+}

hadoop-tools/hadoop-distcp/src/test/java/org/apache/hadoop/tools/TestOptionsParser.java

@@ -715,19 +715,6 @@ public class TestOptionsParser {
       fail("Got unexpected IllegalArgumentException: " + e.getMessage());
     }
 
-    try {
-      options = OptionsParser.parse(new String[] {
-          "-diff", "s1", "s2", "-delete",
-          "hdfs://localhost:9820/source/first",
-          "hdfs://localhost:9820/target/" });
-      fail("-diff should fail if -update option is not specified");
-    } catch (IllegalArgumentException e) {
-      assertFalse("-delete should be ignored when -diff is specified",
-          options.shouldDeleteMissing());
-      GenericTestUtils.assertExceptionContains(
-          "Diff is valid only with update options", e);
-    }
-
     try {
       OptionsParser.parse(new String[] { "-diff", "s1", "s2",
           "-delete", "-overwrite",