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.accumulo.fate.zookeeper; import java.lang.reflect.Method; import java.util.Collections; import java.util.List; import org.apache.accumulo.fate.zookeeper.IZooReaderWriter.Mutator; import org.apache.zookeeper.CreateMode; import org.apache.zookeeper.KeeperException; import org.apache.zookeeper.KeeperException.BadVersionException; import org.apache.zookeeper.KeeperException.Code; import org.apache.zookeeper.KeeperException.ConnectionLossException; import org.apache.zookeeper.KeeperException.NoNodeException; import org.apache.zookeeper.KeeperException.NodeExistsException; import org.apache.zookeeper.KeeperException.SessionExpiredException; import org.apache.zookeeper.ZooKeeper; import org.apache.zookeeper.data.ACL; import org.apache.zookeeper.data.Stat; import org.easymock.EasyMock; import org.junit.Assert; import org.junit.Before; import org.junit.Test; public class ZooReaderWriterTest { private ZooReaderWriter zrw; private ZooKeeper zk; private RetryFactory retryFactory; private Retry retry; @Before public void setup() { zk = EasyMock.createMock(ZooKeeper.class); zrw = EasyMock.createMockBuilder(ZooReaderWriter.class).addMockedMethods("getRetryFactory", "getZooKeeper") .createMock(); retryFactory = EasyMock.createMock(RetryFactory.class); retry = EasyMock.createMock(Retry.class); EasyMock.expect(zrw.getZooKeeper()).andReturn(zk).anyTimes(); EasyMock.expect(zrw.getRetryFactory()).andReturn(retryFactory).anyTimes(); EasyMock.expect(retryFactory.create()).andReturn(retry).anyTimes(); } @Test(expected = NoNodeException.class) public void testDeleteFailOnInitialNoNode() throws Exception { final String path = "/foo"; final int version = -1; zk.delete(path, version); EasyMock.expectLastCall().andThrow(KeeperException.create(Code.NONODE)); EasyMock.expect(retry.hasRetried()).andReturn(false); EasyMock.replay(zk, zrw, retryFactory, retry); zrw.delete(path, version); } @Test public void testDeleteFailOnRetry() throws Exception { final String path = "/foo"; final int version = -1; zk.delete(path, version); EasyMock.expectLastCall().andThrow(KeeperException.create(Code.CONNECTIONLOSS)); EasyMock.expect(retry.canRetry()).andReturn(true); retry.useRetry(); EasyMock.expectLastCall().once(); retry.waitForNextAttempt(); EasyMock.expectLastCall().once(); zk.delete(path, version); EasyMock.expectLastCall().andThrow(KeeperException.create(Code.NONODE)); EasyMock.expect(retry.hasRetried()).andReturn(true); EasyMock.replay(zk, zrw, retryFactory, retry); zrw.delete(path, version); EasyMock.verify(zk, zrw, retryFactory, retry); } @Test(expected = SessionExpiredException.class) public void testMutateNodeCreationFails() throws Exception { final String path = "/foo"; final byte[] value = new byte[] { 0 }; final List<ACL> acls = Collections.<ACL>emptyList(); Mutator mutator = new Mutator() { @Override public byte[] mutate(byte[] currentValue) throws Exception { return new byte[] { 1 }; } }; zk.create(path, value, acls, CreateMode.PERSISTENT); EasyMock.expectLastCall().andThrow(new SessionExpiredException()).once(); EasyMock.expect(retry.canRetry()).andReturn(false); EasyMock.expect(retry.retriesCompleted()).andReturn(1l).once(); EasyMock.replay(zk, zrw, retryFactory, retry); zrw.mutate(path, value, acls, mutator); } @Test public void testMutateWithBadVersion() throws Exception { final String path = "/foo"; final byte[] value = new byte[] { 0 }; final List<ACL> acls = Collections.<ACL>emptyList(); final byte[] mutatedBytes = new byte[] { 1 }; Mutator mutator = new Mutator() { @Override public byte[] mutate(byte[] currentValue) throws Exception { return mutatedBytes; } }; Method getDataMethod = ZooReaderWriter.class.getMethod("getData", String.class, boolean.class, Stat.class); zrw = EasyMock.createMockBuilder(ZooReaderWriter.class).addMockedMethods("getRetryFactory", "getZooKeeper") .addMockedMethod(getDataMethod).createMock(); EasyMock.expect(zrw.getRetryFactory()).andReturn(retryFactory).anyTimes(); EasyMock.expect(zrw.getZooKeeper()).andReturn(zk).anyTimes(); Stat stat = new Stat(); zk.create(path, value, acls, CreateMode.PERSISTENT); EasyMock.expectLastCall().andThrow(new NodeExistsException()).once(); EasyMock.expect(zrw.getData(path, false, stat)).andReturn(new byte[] { 3 }).times(2); // BadVersionException should retry EasyMock.expect(zk.setData(path, mutatedBytes, 0)).andThrow(new BadVersionException()); // Let 2nd setData succeed EasyMock.expect(zk.setData(path, mutatedBytes, 0)).andReturn(null); EasyMock.replay(zk, zrw, retryFactory, retry); Assert.assertArrayEquals(new byte[] { 1 }, zrw.mutate(path, value, acls, mutator)); EasyMock.verify(zk, zrw, retryFactory, retry); } @Test public void testMutateWithRetryOnSetData() throws Exception { final String path = "/foo"; final byte[] value = new byte[] { 0 }; final List<ACL> acls = Collections.<ACL>emptyList(); final byte[] mutatedBytes = new byte[] { 1 }; Mutator mutator = new Mutator() { @Override public byte[] mutate(byte[] currentValue) throws Exception { return mutatedBytes; } }; Method getDataMethod = ZooReaderWriter.class.getMethod("getData", String.class, boolean.class, Stat.class); zrw = EasyMock.createMockBuilder(ZooReaderWriter.class).addMockedMethods("getRetryFactory", "getZooKeeper") .addMockedMethod(getDataMethod).createMock(); EasyMock.expect(zrw.getRetryFactory()).andReturn(retryFactory).anyTimes(); EasyMock.expect(zrw.getZooKeeper()).andReturn(zk).anyTimes(); Stat stat = new Stat(); zk.create(path, value, acls, CreateMode.PERSISTENT); EasyMock.expectLastCall().andThrow(new NodeExistsException()).once(); EasyMock.expect(zrw.getData(path, false, stat)).andReturn(new byte[] { 3 }).times(2); // BadVersionException should retry EasyMock.expect(zk.setData(path, mutatedBytes, 0)).andThrow(new ConnectionLossException()); EasyMock.expect(retry.canRetry()).andReturn(true); retry.useRetry(); EasyMock.expectLastCall(); retry.waitForNextAttempt(); EasyMock.expectLastCall(); // Let 2nd setData succeed EasyMock.expect(zk.setData(path, mutatedBytes, 0)).andReturn(null); EasyMock.replay(zk, zrw, retryFactory, retry); Assert.assertArrayEquals(new byte[] { 1 }, zrw.mutate(path, value, acls, mutator)); EasyMock.verify(zk, zrw, retryFactory, retry); } }