Java tutorial
/** * 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.hbase.client; import static org.apache.hadoop.hbase.HConstants.EMPTY_START_ROW; import static org.apache.hadoop.hbase.HConstants.HBASE_CLIENT_META_OPERATION_TIMEOUT; import static org.apache.hadoop.hbase.coprocessor.CoprocessorHost.REGION_COPROCESSOR_CONF_KEY; import static org.hamcrest.CoreMatchers.instanceOf; import static org.junit.Assert.assertEquals; import static org.junit.Assert.assertThat; import static org.junit.Assert.assertTrue; import static org.junit.Assert.fail; import java.io.IOException; import java.util.Optional; import java.util.concurrent.CompletionException; import java.util.concurrent.ExecutionException; import java.util.concurrent.TimeUnit; import java.util.concurrent.atomic.AtomicReference; import org.apache.commons.io.IOUtils; import org.apache.hadoop.conf.Configuration; import org.apache.hadoop.hbase.HBaseClassTestRule; import org.apache.hadoop.hbase.HBaseTestingUtility; import org.apache.hadoop.hbase.HRegionLocation; import org.apache.hadoop.hbase.TableName; import org.apache.hadoop.hbase.TableNotFoundException; import org.apache.hadoop.hbase.coprocessor.ObserverContext; import org.apache.hadoop.hbase.coprocessor.RegionCoprocessor; import org.apache.hadoop.hbase.coprocessor.RegionCoprocessorEnvironment; import org.apache.hadoop.hbase.coprocessor.RegionObserver; import org.apache.hadoop.hbase.exceptions.TimeoutIOException; import org.apache.hadoop.hbase.security.User; import org.apache.hadoop.hbase.testclassification.ClientTests; import org.apache.hadoop.hbase.testclassification.MediumTests; import org.apache.hadoop.hbase.util.Bytes; import org.apache.hadoop.hbase.util.Threads; import org.junit.After; import org.junit.AfterClass; import org.junit.BeforeClass; import org.junit.ClassRule; import org.junit.Test; import org.junit.experimental.categories.Category; @Category({ MediumTests.class, ClientTests.class }) public class TestAsyncRegionLocator { @ClassRule public static final HBaseClassTestRule CLASS_RULE = HBaseClassTestRule.forClass(TestAsyncRegionLocator.class); private static final HBaseTestingUtility TEST_UTIL = new HBaseTestingUtility(); private static TableName TABLE_NAME = TableName.valueOf("async"); private static byte[] FAMILY = Bytes.toBytes("cf"); private static AsyncConnectionImpl CONN; private static AsyncRegionLocator LOCATOR; private static volatile long SLEEP_MS = 0L; public static class SleepRegionObserver implements RegionCoprocessor, RegionObserver { @Override public Optional<RegionObserver> getRegionObserver() { return Optional.of(this); } @Override public void preScannerOpen(ObserverContext<RegionCoprocessorEnvironment> e, Scan scan) throws IOException { if (SLEEP_MS > 0) { Threads.sleepWithoutInterrupt(SLEEP_MS); } } } @BeforeClass public static void setUp() throws Exception { Configuration conf = TEST_UTIL.getConfiguration(); conf.set(REGION_COPROCESSOR_CONF_KEY, SleepRegionObserver.class.getName()); conf.setLong(HBASE_CLIENT_META_OPERATION_TIMEOUT, 2000); TEST_UTIL.startMiniCluster(1); TEST_UTIL.createTable(TABLE_NAME, FAMILY); TEST_UTIL.waitTableAvailable(TABLE_NAME); AsyncRegistry registry = AsyncRegistryFactory.getRegistry(TEST_UTIL.getConfiguration()); CONN = new AsyncConnectionImpl(TEST_UTIL.getConfiguration(), registry, registry.getClusterId().get(), User.getCurrent()); LOCATOR = CONN.getLocator(); } @AfterClass public static void tearDown() throws Exception { IOUtils.closeQuietly(CONN); TEST_UTIL.shutdownMiniCluster(); } @After public void tearDownAfterTest() { LOCATOR.clearCache(); } @Test public void testTimeout() throws InterruptedException, ExecutionException { SLEEP_MS = 1000; long startNs = System.nanoTime(); try { LOCATOR.getRegionLocation(TABLE_NAME, EMPTY_START_ROW, RegionLocateType.CURRENT, TimeUnit.MILLISECONDS.toNanos(500)).get(); fail(); } catch (ExecutionException e) { assertThat(e.getCause(), instanceOf(TimeoutIOException.class)); } long costMs = TimeUnit.NANOSECONDS.toMillis(System.nanoTime() - startNs); assertTrue(costMs >= 500); assertTrue(costMs < 1000); // wait for the background task finish Thread.sleep(2000); // Now the location should be in cache, so we will not visit meta again. HRegionLocation loc = LOCATOR.getRegionLocation(TABLE_NAME, EMPTY_START_ROW, RegionLocateType.CURRENT, TimeUnit.MILLISECONDS.toNanos(500)).get(); assertEquals(loc.getServerName(), TEST_UTIL.getHBaseCluster().getRegionServer(0).getServerName()); } @Test public void testNoCompletionException() { // make sure that we do not get CompletionException SLEEP_MS = 0; AtomicReference<Throwable> errorHolder = new AtomicReference<>(); try { LOCATOR.getRegionLocation(TableName.valueOf("NotExist"), EMPTY_START_ROW, RegionLocateType.CURRENT, TimeUnit.SECONDS.toNanos(1)).whenComplete((r, e) -> errorHolder.set(e)).join(); fail(); } catch (CompletionException e) { // join will return a CompletionException, which is OK assertThat(e.getCause(), instanceOf(TableNotFoundException.class)); } // but we need to make sure that we do not get a CompletionException in the callback assertThat(errorHolder.get(), instanceOf(TableNotFoundException.class)); } }