Java ZKAssign.deleteAllNodes方法代码示例

import org.apache.hadoop.hbase.zookeeper.ZKAssign; //导入方法依赖的package包/类
/**
 * Run a simple server shutdown handler.
 * @throws KeeperException
 * @throws IOException
 */
@Test
public void testShutdownHandler() throws KeeperException, IOException {
  // Create and startup an executor.  This is used by AssignmentManager
  // handling zk callbacks.
  ExecutorService executor = startupMasterExecutor("testShutdownHandler");

  // We need a mocked catalog tracker.
  CatalogTracker ct = Mockito.mock(CatalogTracker.class);
  LoadBalancer balancer = LoadBalancerFactory.getLoadBalancer(server
      .getConfiguration());
  // Create an AM.
  AssignmentManager am =
    new AssignmentManager(this.server, this.serverManager, ct, balancer, executor);
  try {
    processServerShutdownHandler(ct, am, false, null);
  } finally {
    executor.shutdown();
    am.shutdown();
    // Clean up all znodes
    ZKAssign.deleteAllNodes(this.watcher);
  }
}
 

import org.apache.hadoop.hbase.zookeeper.ZKAssign; //导入方法依赖的package包/类
/**
 * Run a simple server shutdown handler.
 * @throws KeeperException
 * @throws IOException
 */
@Test (timeout=180000)
public void testShutdownHandler()
    throws KeeperException, IOException, CoordinatedStateException, ServiceException {
  // Create and startup an executor.  This is used by AssignmentManager
  // handling zk callbacks.
  ExecutorService executor = startupMasterExecutor("testShutdownHandler");

  // Create an AM.
  AssignmentManagerWithExtrasForTesting am = setUpMockedAssignmentManager(
      this.server, this.serverManager);
  try {
    processServerShutdownHandler(am, false);
  } finally {
    executor.shutdown();
    am.shutdown();
    // Clean up all znodes
    ZKAssign.deleteAllNodes(this.watcher);
  }
}
 

import org.apache.hadoop.hbase.zookeeper.ZKAssign; //导入方法依赖的package包/类
/**
 * Run a simple server shutdown handler.
 * @throws KeeperException
 * @throws IOException
 */
@Test
public void testShutdownHandler()
    throws KeeperException, IOException, ServiceException {
  // Create and startup an executor.  This is used by AssignmentManager
  // handling zk callbacks.
  ExecutorService executor = startupMasterExecutor("testShutdownHandler");

  // We need a mocked catalog tracker.
  CatalogTracker ct = Mockito.mock(CatalogTracker.class);
  // Create an AM.
  AssignmentManagerWithExtrasForTesting am = setUpMockedAssignmentManager(
      this.server, this.serverManager);
  try {
    processServerShutdownHandler(ct, am, false);
  } finally {
    executor.shutdown();
    am.shutdown();
    // Clean up all znodes
    ZKAssign.deleteAllNodes(this.watcher);
  }
}
 

import org.apache.hadoop.hbase.zookeeper.ZKAssign; //导入方法依赖的package包/类
/**
 * Reset all unassigned znodes.  Called on startup of master.
 * Call {@link #assignAllUserRegions()} after root and meta have been assigned.
 * @throws IOException
 * @throws KeeperException
 */
void cleanoutUnassigned() throws IOException, KeeperException {
  // Cleanup any existing ZK nodes and start watching
  ZKAssign.deleteAllNodes(watcher);
  ZKUtil.listChildrenAndWatchForNewChildren(this.watcher,
    this.watcher.assignmentZNode);
}
 

import org.apache.hadoop.hbase.zookeeper.ZKAssign; //导入方法依赖的package包/类
@After
  public void after() throws KeeperException {
  if (this.watcher != null) {
    // Clean up all znodes
    ZKAssign.deleteAllNodes(this.watcher);
    this.watcher.close();
  }
}
 

import org.apache.hadoop.hbase.zookeeper.ZKAssign; //导入方法依赖的package包/类
@After public void after() throws KeeperException, IOException {
  if (this.watcher != null) {
    // Clean up all znodes
    ZKAssign.deleteAllNodes(this.watcher);
    this.watcher.close();
    this.cp.stop();
  }
  if (this.connection != null) this.connection.close();
}
 

import org.apache.hadoop.hbase.zookeeper.ZKAssign; //导入方法依赖的package包/类
/**
 * Assigns all user regions, if any exist.  Used during cluster startup.
 * <p>
 * This is a synchronous call and will return once every region has been
 * assigned.  If anything fails, an exception is thrown and the cluster
 * should be shutdown.
 * @throws InterruptedException
 * @throws IOException
 * @throws KeeperException
 */
private void assignAllUserRegions()
    throws IOException, InterruptedException, KeeperException {
  // Cleanup any existing ZK nodes and start watching
  ZKAssign.deleteAllNodes(watcher);
  ZKUtil.listChildrenAndWatchForNewChildren(this.watcher,
    this.watcher.assignmentZNode);
  failoverCleanupDone();

  // Skip assignment for regions of tables in DISABLING state because during clean cluster startup
  // no RS is alive and regions map also doesn't have any information about the regions.
  // See HBASE-6281.
  Set<TableName> disabledOrDisablingOrEnabling = ZKTable.getDisabledOrDisablingTables(watcher);
  disabledOrDisablingOrEnabling.addAll(ZKTable.getEnablingTables(watcher));
  // Scan hbase:meta for all user regions, skipping any disabled tables
  Map<HRegionInfo, ServerName> allRegions;
  SnapshotOfRegionAssignmentFromMeta snapshotOfRegionAssignment =
     new SnapshotOfRegionAssignmentFromMeta(catalogTracker, disabledOrDisablingOrEnabling, true);
  snapshotOfRegionAssignment.initialize();
  allRegions = snapshotOfRegionAssignment.getRegionToRegionServerMap();
  if (allRegions == null || allRegions.isEmpty()) return;

  // Determine what type of assignment to do on startup
  boolean retainAssignment = server.getConfiguration().
    getBoolean("hbase.master.startup.retainassign", true);

  if (retainAssignment) {
    assign(allRegions);
  } else {
    List<HRegionInfo> regions = new ArrayList<HRegionInfo>(allRegions.keySet());
    assign(regions);
  }

  for (HRegionInfo hri : allRegions.keySet()) {
    TableName tableName = hri.getTable();
    if (!zkTable.isEnabledTable(tableName)) {
      setEnabledTable(tableName);
    }
  }
}
 

import org.apache.hadoop.hbase.zookeeper.ZKAssign; //导入方法依赖的package包/类
/**
 * Test verifies whether all the enabling table regions assigned only once during master startup.
 *
 * @throws KeeperException
 * @throws IOException
 * @throws Exception
 */
@Test
public void testMasterRestartWhenTableInEnabling() throws KeeperException, IOException, Exception {
  enabling = true;
  List<ServerName> destServers = new ArrayList<ServerName>(1);
  destServers.add(SERVERNAME_A);
  Mockito.when(this.serverManager.createDestinationServersList()).thenReturn(destServers);
  Mockito.when(this.serverManager.isServerOnline(SERVERNAME_A)).thenReturn(true);
  HTU.getConfiguration().setInt(HConstants.MASTER_PORT, 0);
  Server server = new HMaster(HTU.getConfiguration());
  Whitebox.setInternalState(server, "serverManager", this.serverManager);
  AssignmentManagerWithExtrasForTesting am = setUpMockedAssignmentManager(server,
      this.serverManager);
  try {
    // set table in enabling state.
    am.getZKTable().setEnablingTable(REGIONINFO.getTable());
    new EnableTableHandler(server, REGIONINFO.getTable(),
        am.getCatalogTracker(), am, new NullTableLockManager(), true).prepare()
        .process();
    assertEquals("Number of assignments should be 1.", 1, assignmentCount);
    assertTrue("Table should be enabled.",
        am.getZKTable().isEnabledTable(REGIONINFO.getTable()));
  } finally {
    enabling = false;
    assignmentCount = 0;
    am.getZKTable().setEnabledTable(REGIONINFO.getTable());
    am.shutdown();
    ZKAssign.deleteAllNodes(this.watcher);
  }
}
 

import org.apache.hadoop.hbase.zookeeper.ZKAssign; //导入方法依赖的package包/类
/**
 * Tests AssignmentManager balance function.  Runs a balance moving a region
 * from one server to another mocking regionserver responding over zk.
 * @throws IOException
 * @throws KeeperException
 * @throws InterruptedException
 */
@Test(timeout = 60000)
public void testBalance()
throws IOException, KeeperException, InterruptedException {
  // Create and startup an executor.  This is used by AssignmentManager
  // handling zk callbacks.
  ExecutorService executor = startupMasterExecutor("testBalanceExecutor");

  // We need a mocked catalog tracker.
  CatalogTracker ct = Mockito.mock(CatalogTracker.class);
  LoadBalancer balancer = LoadBalancerFactory.getLoadBalancer(server
      .getConfiguration());
  // Create an AM.
  AssignmentManager am = new AssignmentManager(this.server,
      this.serverManager, ct, balancer, executor);
  try {
    // Make sure our new AM gets callbacks; once registered, can't unregister.
    // Thats ok because we make a new zk watcher for each test.
    this.watcher.registerListenerFirst(am);
    // Call the balance function but fake the region being online first at
    // SERVERNAME_A.  Create a balance plan.
    am.regionOnline(REGIONINFO, SERVERNAME_A);
    // Balance region from A to B.
    RegionPlan plan = new RegionPlan(REGIONINFO, SERVERNAME_A, SERVERNAME_B);
    am.balance(plan);

    // Now fake the region closing successfully over on the regionserver; the
    // regionserver will have set the region in CLOSED state.  This will
    // trigger callback into AM. The below zk close call is from the RS close
    // region handler duplicated here because its down deep in a private
    // method hard to expose.
    int versionid =
      ZKAssign.transitionNodeClosed(this.watcher, REGIONINFO, SERVERNAME_A, -1);
    assertNotSame(versionid, -1);
    // AM is going to notice above CLOSED and queue up a new assign.  The
    // assign will go to open the region in the new location set by the
    // balancer.  The zk node will be OFFLINE waiting for regionserver to
    // transition it through OPENING, OPENED.  Wait till we see the RIT
    // before we proceed.
    Mocking.waitForRegionOfflineInRIT(am, REGIONINFO.getEncodedName());
    // Get current versionid else will fail on transition from OFFLINE to OPENING below
    while (true) {
      int vid = ZKAssign.getVersion(this.watcher, REGIONINFO);
      if (vid != versionid) {
        versionid = vid;
        break;
      }
    }
    assertNotSame(-1, versionid);
    // This uglyness below is what the openregionhandler on RS side does.
    versionid = ZKAssign.transitionNode(server.getZooKeeper(), REGIONINFO,
      SERVERNAME_A, EventType.M_ZK_REGION_OFFLINE,
      EventType.RS_ZK_REGION_OPENING, versionid);
    assertNotSame(-1, versionid);
    // Move znode from OPENING to OPENED as RS does on successful open.
    versionid =
      ZKAssign.transitionNodeOpened(this.watcher, REGIONINFO, SERVERNAME_B, versionid);
    assertNotSame(-1, versionid);
    // Wait on the handler removing the OPENED znode.
    while(am.isRegionInTransition(REGIONINFO) != null) Threads.sleep(1);
  } finally {
    executor.shutdown();
    am.shutdown();
    // Clean up all znodes
    ZKAssign.deleteAllNodes(this.watcher);
  }
}
 

import org.apache.hadoop.hbase.zookeeper.ZKAssign; //导入方法依赖的package包/类
private void testCaseWithSplitRegionPartial(boolean regionSplitDone) throws KeeperException, IOException,
    NodeExistsException, InterruptedException {
  // Create and startup an executor. This is used by AssignmentManager
  // handling zk callbacks.
  ExecutorService executor = startupMasterExecutor("testSSHWhenSplitRegionInProgress");

  // We need a mocked catalog tracker.
  CatalogTracker ct = Mockito.mock(CatalogTracker.class);
  // Create an AM.
  AssignmentManagerWithExtrasForTesting am = setUpMockedAssignmentManager(this.server, this.serverManager);
  // adding region to regions and servers maps.
  am.regionOnline(REGIONINFO, SERVERNAME_A);
  // adding region in pending close.
  am.regionsInTransition.put(REGIONINFO.getEncodedName(), new RegionState(REGIONINFO,
      State.SPLITTING, System.currentTimeMillis(), SERVERNAME_A));
  am.getZKTable().setEnabledTable(REGIONINFO.getTableNameAsString());

  RegionTransitionData data = new RegionTransitionData(EventType.RS_ZK_REGION_SPLITTING,
      REGIONINFO.getRegionName(), SERVERNAME_A);
  String node = ZKAssign.getNodeName(this.watcher, REGIONINFO.getEncodedName());
  // create znode in M_ZK_REGION_CLOSING state.
  ZKUtil.createAndWatch(this.watcher, node, data.getBytes());

  try {
    processServerShutdownHandler(ct, am, regionSplitDone, null);
    // check znode deleted or not.
    // In both cases the znode should be deleted.

    if(regionSplitDone){
      assertTrue("Region state of region in SPLITTING should be removed from rit.",
          am.regionsInTransition.isEmpty());
    }
    else{
      while (!am.assignInvoked) {
        Thread.sleep(1);
      }
      assertTrue("Assign should be invoked.", am.assignInvoked);
    }
  } finally {
    REGIONINFO.setOffline(false);
    REGIONINFO.setSplit(false);
    executor.shutdown();
    am.shutdown();
    // Clean up all znodes
    ZKAssign.deleteAllNodes(this.watcher);
  }
}
 

import org.apache.hadoop.hbase.zookeeper.ZKAssign; //导入方法依赖的package包/类
/**
 * Tests AssignmentManager balance function.  Runs a balance moving a region
 * from one server to another mocking regionserver responding over zk.
 * @throws IOException
 * @throws KeeperException
 * @throws DeserializationException
 */
@Test (timeout=180000)
public void testBalance() throws IOException, KeeperException, DeserializationException,
    InterruptedException, CoordinatedStateException {
  // Create and startup an executor.  This is used by AssignmentManager
  // handling zk callbacks.
  ExecutorService executor = startupMasterExecutor("testBalanceExecutor");

  // We need a mocked catalog tracker.
  LoadBalancer balancer = LoadBalancerFactory.getLoadBalancer(server
      .getConfiguration());
  // Create an AM.
  AssignmentManager am = new AssignmentManager(this.server,
    this.serverManager, balancer, executor, null, master.getTableLockManager());
  am.failoverCleanupDone.set(true);
  try {
    // Make sure our new AM gets callbacks; once registered, can't unregister.
    // Thats ok because we make a new zk watcher for each test.
    this.watcher.registerListenerFirst(am);
    // Call the balance function but fake the region being online first at
    // SERVERNAME_A.  Create a balance plan.
    am.regionOnline(REGIONINFO, SERVERNAME_A);
    // Balance region from A to B.
    RegionPlan plan = new RegionPlan(REGIONINFO, SERVERNAME_A, SERVERNAME_B);
    am.balance(plan);

    RegionStates regionStates = am.getRegionStates();
    // Must be failed to close since the server is fake
    assertTrue(regionStates.isRegionInTransition(REGIONINFO)
      && regionStates.isRegionInState(REGIONINFO, State.FAILED_CLOSE));
    // Move it back to pending_close
    regionStates.updateRegionState(REGIONINFO, State.PENDING_CLOSE);

    // Now fake the region closing successfully over on the regionserver; the
    // regionserver will have set the region in CLOSED state.  This will
    // trigger callback into AM. The below zk close call is from the RS close
    // region handler duplicated here because its down deep in a private
    // method hard to expose.
    int versionid =
      ZKAssign.transitionNodeClosed(this.watcher, REGIONINFO, SERVERNAME_A, -1);
    assertNotSame(versionid, -1);
    // AM is going to notice above CLOSED and queue up a new assign.  The
    // assign will go to open the region in the new location set by the
    // balancer.  The zk node will be OFFLINE waiting for regionserver to
    // transition it through OPENING, OPENED.  Wait till we see the OFFLINE
    // zk node before we proceed.
    Mocking.waitForRegionPendingOpenInRIT(am, REGIONINFO.getEncodedName());

    // Get current versionid else will fail on transition from OFFLINE to OPENING below
    versionid = ZKAssign.getVersion(this.watcher, REGIONINFO);
    assertNotSame(-1, versionid);
    // This uglyness below is what the openregionhandler on RS side does.
    versionid = ZKAssign.transitionNode(server.getZooKeeper(), REGIONINFO,
      SERVERNAME_B, EventType.M_ZK_REGION_OFFLINE,
      EventType.RS_ZK_REGION_OPENING, versionid);
    assertNotSame(-1, versionid);
    // Move znode from OPENING to OPENED as RS does on successful open.
    versionid =
      ZKAssign.transitionNodeOpened(this.watcher, REGIONINFO, SERVERNAME_B, versionid);
    assertNotSame(-1, versionid);
    // Wait on the handler removing the OPENED znode.
    while(regionStates.isRegionInTransition(REGIONINFO)) Threads.sleep(1);
  } finally {
    executor.shutdown();
    am.shutdown();
    // Clean up all znodes
    ZKAssign.deleteAllNodes(this.watcher);
  }
}
 

import org.apache.hadoop.hbase.zookeeper.ZKAssign; //导入方法依赖的package包/类
private void testCaseWithSplitRegionPartial(boolean regionSplitDone) throws KeeperException,
    IOException, InterruptedException,
  CoordinatedStateException, ServiceException {
  // Create and startup an executor. This is used by AssignmentManager
  // handling zk callbacks.
  ExecutorService executor = startupMasterExecutor("testSSHWhenSplitRegionInProgress");
  // We need a mocked catalog tracker.
  ZKAssign.deleteAllNodes(this.watcher);

  // Create an AM.
  AssignmentManagerWithExtrasForTesting am = setUpMockedAssignmentManager(
    this.server, this.serverManager);
  // adding region to regions and servers maps.
  am.regionOnline(REGIONINFO, SERVERNAME_A);
  // adding region in pending close.
  am.getRegionStates().updateRegionState(
    REGIONINFO, State.SPLITTING, SERVERNAME_A);
  am.getTableStateManager().setTableState(REGIONINFO.getTable(),
    Table.State.ENABLED);
  RegionTransition data = RegionTransition.createRegionTransition(EventType.RS_ZK_REGION_SPLITTING,
      REGIONINFO.getRegionName(), SERVERNAME_A);
  String node = ZKAssign.getNodeName(this.watcher, REGIONINFO.getEncodedName());
  // create znode in M_ZK_REGION_CLOSING state.
  ZKUtil.createAndWatch(this.watcher, node, data.toByteArray());

  try {
    processServerShutdownHandler(am, regionSplitDone);
    // check znode deleted or not.
    // In both cases the znode should be deleted.

    if (regionSplitDone) {
      assertFalse("Region state of region in SPLITTING should be removed from rit.",
          am.getRegionStates().isRegionsInTransition());
    } else {
      while (!am.assignInvoked) {
        Thread.sleep(1);
      }
      assertTrue("Assign should be invoked.", am.assignInvoked);
    }
  } finally {
    REGIONINFO.setOffline(false);
    REGIONINFO.setSplit(false);
    executor.shutdown();
    am.shutdown();
    // Clean up all znodes
    ZKAssign.deleteAllNodes(this.watcher);
  }
}
 

import org.apache.hadoop.hbase.zookeeper.ZKAssign; //导入方法依赖的package包/类
private void testCaseWithPartiallyDisabledState(Table.State state) throws KeeperException,
    IOException, CoordinatedStateException, ServiceException {
  // Create and startup an executor. This is used by AssignmentManager
  // handling zk callbacks.
  ExecutorService executor = startupMasterExecutor("testSSHWhenDisableTableInProgress");
  LoadBalancer balancer = LoadBalancerFactory.getLoadBalancer(server.getConfiguration());
  ZKAssign.deleteAllNodes(this.watcher);

  // Create an AM.
  AssignmentManager am = new AssignmentManager(this.server,
    this.serverManager, balancer, executor, null, master.getTableLockManager());
  // adding region to regions and servers maps.
  am.regionOnline(REGIONINFO, SERVERNAME_A);
  // adding region in pending close.
  am.getRegionStates().updateRegionState(REGIONINFO, State.PENDING_CLOSE);
  if (state == Table.State.DISABLING) {
    am.getTableStateManager().setTableState(REGIONINFO.getTable(),
      Table.State.DISABLING);
  } else {
    am.getTableStateManager().setTableState(REGIONINFO.getTable(),
      Table.State.DISABLED);
  }
  RegionTransition data = RegionTransition.createRegionTransition(EventType.M_ZK_REGION_CLOSING,
      REGIONINFO.getRegionName(), SERVERNAME_A);
  // RegionTransitionData data = new
  // RegionTransitionData(EventType.M_ZK_REGION_CLOSING,
  // REGIONINFO.getRegionName(), SERVERNAME_A);
  String node = ZKAssign.getNodeName(this.watcher, REGIONINFO.getEncodedName());
  // create znode in M_ZK_REGION_CLOSING state.
  ZKUtil.createAndWatch(this.watcher, node, data.toByteArray());

  try {
    processServerShutdownHandler(am, false);
    // check znode deleted or not.
    // In both cases the znode should be deleted.
    assertTrue("The znode should be deleted.", ZKUtil.checkExists(this.watcher, node) == -1);
    // check whether in rit or not. In the DISABLING case also the below
    // assert will be true but the piece of code added for HBASE-5927 will not
    // do that.
    if (state == Table.State.DISABLED) {
      assertFalse("Region state of region in pending close should be removed from rit.",
          am.getRegionStates().isRegionsInTransition());
    }
  } finally {
    am.setEnabledTable(REGIONINFO.getTable());
    executor.shutdown();
    am.shutdown();
    // Clean up all znodes
    ZKAssign.deleteAllNodes(this.watcher);
  }
}
 

import org.apache.hadoop.hbase.zookeeper.ZKAssign; //导入方法依赖的package包/类
/**
 * Test verifies whether all the enabling table regions assigned only once during master startup.
 *
 * @throws KeeperException
 * @throws IOException
 * @throws Exception
 */
@Test (timeout=180000)
public void testMasterRestartWhenTableInEnabling() throws KeeperException, IOException, Exception {
  enabling = true;
  List<ServerName> destServers = new ArrayList<ServerName>(1);
  destServers.add(SERVERNAME_A);
  Mockito.when(this.serverManager.createDestinationServersList()).thenReturn(destServers);
  Mockito.when(this.serverManager.isServerOnline(SERVERNAME_A)).thenReturn(true);
  HTU.getConfiguration().setInt(HConstants.MASTER_PORT, 0);
  CoordinatedStateManager csm = CoordinatedStateManagerFactory.getCoordinatedStateManager(
    HTU.getConfiguration());
  Server server = new HMaster(HTU.getConfiguration(), csm);
  Whitebox.setInternalState(server, "serverManager", this.serverManager);
  AssignmentManagerWithExtrasForTesting am = setUpMockedAssignmentManager(server,
      this.serverManager);

  Whitebox.setInternalState(server, "metaTableLocator", Mockito.mock(MetaTableLocator.class));

  // Make it so we can get a catalogtracker from servermanager.. .needed
  // down in guts of server shutdown handler.
  Whitebox.setInternalState(server, "clusterConnection", am.getConnection());

  try {
    // set table in enabling state.
    am.getTableStateManager().setTableState(REGIONINFO.getTable(),
      Table.State.ENABLING);
    new EnableTableHandler(server, REGIONINFO.getTable(),
        am, new NullTableLockManager(), true).prepare()
        .process();
    assertEquals("Number of assignments should be 1.", 1, assignmentCount);
    assertTrue("Table should be enabled.",
        am.getTableStateManager().isTableState(REGIONINFO.getTable(),
          Table.State.ENABLED));
  } finally {
    enabling = false;
    assignmentCount = 0;
    am.getTableStateManager().setTableState(REGIONINFO.getTable(),
      Table.State.ENABLED);
    am.shutdown();
    ZKAssign.deleteAllNodes(this.watcher);
  }
}
 

import org.apache.hadoop.hbase.zookeeper.ZKAssign; //导入方法依赖的package包/类
/**
 * Tests AssignmentManager balance function.  Runs a balance moving a region
 * from one server to another mocking regionserver responding over zk.
 * @throws IOException
 * @throws KeeperException
 * @throws DeserializationException
 */
@Test
public void testBalance()
  throws IOException, KeeperException, DeserializationException, InterruptedException {
  // Create and startup an executor.  This is used by AssignmentManager
  // handling zk callbacks.
  ExecutorService executor = startupMasterExecutor("testBalanceExecutor");

  // We need a mocked catalog tracker.
  CatalogTracker ct = Mockito.mock(CatalogTracker.class);
  LoadBalancer balancer = LoadBalancerFactory.getLoadBalancer(server
      .getConfiguration());
  // Create an AM.
  AssignmentManager am = new AssignmentManager(this.server,
    this.serverManager, ct, balancer, executor, null, master.getTableLockManager());
  am.failoverCleanupDone.set(true);
  try {
    // Make sure our new AM gets callbacks; once registered, can't unregister.
    // Thats ok because we make a new zk watcher for each test.
    this.watcher.registerListenerFirst(am);
    // Call the balance function but fake the region being online first at
    // SERVERNAME_A.  Create a balance plan.
    am.regionOnline(REGIONINFO, SERVERNAME_A);
    // Balance region from A to B.
    RegionPlan plan = new RegionPlan(REGIONINFO, SERVERNAME_A, SERVERNAME_B);
    am.balance(plan);

    RegionStates regionStates = am.getRegionStates();
    // Must be failed to close since the server is fake
    assertTrue(regionStates.isRegionInTransition(REGIONINFO)
      && regionStates.isRegionInState(REGIONINFO, State.FAILED_CLOSE));
    // Move it back to pending_close
    regionStates.updateRegionState(REGIONINFO, State.PENDING_CLOSE);

    // Now fake the region closing successfully over on the regionserver; the
    // regionserver will have set the region in CLOSED state.  This will
    // trigger callback into AM. The below zk close call is from the RS close
    // region handler duplicated here because its down deep in a private
    // method hard to expose.
    int versionid =
      ZKAssign.transitionNodeClosed(this.watcher, REGIONINFO, SERVERNAME_A, -1);
    assertNotSame(versionid, -1);
    // AM is going to notice above CLOSED and queue up a new assign.  The
    // assign will go to open the region in the new location set by the
    // balancer.  The zk node will be OFFLINE waiting for regionserver to
    // transition it through OPENING, OPENED.  Wait till we see the OFFLINE
    // zk node before we proceed.
    Mocking.waitForRegionPendingOpenInRIT(am, REGIONINFO.getEncodedName());

    // Get current versionid else will fail on transition from OFFLINE to OPENING below
    versionid = ZKAssign.getVersion(this.watcher, REGIONINFO);
    assertNotSame(-1, versionid);
    // This uglyness below is what the openregionhandler on RS side does.
    versionid = ZKAssign.transitionNode(server.getZooKeeper(), REGIONINFO,
      SERVERNAME_B, EventType.M_ZK_REGION_OFFLINE,
      EventType.RS_ZK_REGION_OPENING, versionid);
    assertNotSame(-1, versionid);
    // Move znode from OPENING to OPENED as RS does on successful open.
    versionid =
      ZKAssign.transitionNodeOpened(this.watcher, REGIONINFO, SERVERNAME_B, versionid);
    assertNotSame(-1, versionid);
    // Wait on the handler removing the OPENED znode.
    while(regionStates.isRegionInTransition(REGIONINFO)) Threads.sleep(1);
  } finally {
    executor.shutdown();
    am.shutdown();
    // Clean up all znodes
    ZKAssign.deleteAllNodes(this.watcher);
  }
}