content: /*
   * 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.bookkeeper.client;
  
  import static org.junit.Assert.assertEquals;
  import static org.junit.Assert.fail;
  
  import java.util.Arrays;
  import java.util.Enumeration;
  import java.util.concurrent.CountDownLatch;
  import java.util.concurrent.atomic.AtomicInteger;
  import org.apache.bookkeeper.client.AsyncCallback.ReadCallback;
  import org.apache.bookkeeper.client.BKException.Code;
  import org.apache.bookkeeper.client.BookKeeper.DigestType;
  import org.apache.bookkeeper.test.BookKeeperClusterTestCase;
  import org.junit.Test;
  
  /**
    * Test read next entry and the latest last add confirmed.
    */
  public class TestReadLastEntry extends BookKeeperClusterTestCase {
  
      final DigestType digestType;
  
      public TestReadLastEntry() {
          super(1);
          this.digestType = DigestType.CRC32;
      }
  
      @Test
      public void testTryReadLastEntryAsyncOnEmptyLedger() throws Exception {
          final LedgerHandle lh = bkc.createLedger(1, 1, 1, digestType, "".getBytes());
          lh.close();
  
          LedgerHandle readLh = bkc.openLedger(lh.getId(), digestType, "".getBytes());
  
          final CountDownLatch latch1 = new CountDownLatch(1);
          final AtomicInteger rcStore = new AtomicInteger();
          readLh.asyncReadLastEntry(new ReadCallback() {
              @Override
              public void readComplete(int rc, LedgerHandle lh, Enumeration<LedgerEntry> seq, Object ctx) {
                  rcStore.set(rc);
                  latch1.countDown();
              }
          }, null);
  
          latch1.await();
  
          assertEquals(BKException.Code.NoSuchEntryException, rcStore.get());
  
          lh.close();
          readLh.close();
      }
  
      @Test
      public void testTryReadLastEntryOnEmptyLedger() throws Exception {
          final LedgerHandle lh = bkc.createLedger(1, 1, 1, digestType, "".getBytes());
          lh.close();
  
          LedgerHandle readLh = bkc.openLedger(lh.getId(), digestType, "".getBytes());
          try {
              LedgerEntry lastEntry = readLh.readLastEntry();
              fail("should fail with NoSuchEntryException");
          } catch (BKException e) {
              assertEquals(e.getCode(), Code.NoSuchEntryException);
          }
  
          lh.close();
          readLh.close();
      }
  
      @Test
      public void testTryReadLastEntryAsync() throws Exception {
          final LedgerHandle lh = bkc.createLedger(1, 1, 1, digestType, "".getBytes());
          byte[] data = new byte[1024];
          Arrays.fill(data, (byte) 'x');
          for (int j = 0; j < 100; j++) {
              data[1023] = Integer.valueOf(j).byteValue();
              lh.addEntry(data);
          }
          lh.close();
  
          LedgerHandle readLh = bkc.openLedger(lh.getId(), digestType, "".getBytes());
          final CountDownLatch latch1 = new CountDownLatch(1);
          final AtomicInteger rcStore = new AtomicInteger();
          final AtomicInteger lastByteStore = new AtomicInteger();
  
          readLh.asyncReadLastEntry(new ReadCallback() {
              @Override
              public void readComplete(int rc, LedgerHandle lh, Enumeration<LedgerEntry> seq, Object ctx) {
                  rcStore.set(rc);
                  LedgerEntry entry = seq.nextElement();
                  lastByteStore.set(entry.getEntry()[1023]);
                  latch1.countDown();
              }
          }, null);
  
          latch1.await();
  
          assertEquals(BKException.Code.OK, rcStore.get());
          assertEquals(lastByteStore.byteValue(), data[1023]);
  
          lh.close();
          readLh.close();
      }
  
      @Test
      public void testTryReadLastEntrySync() throws Exception {
          final LedgerHandle lh = bkc.createLedger(1, 1, 1, digestType, "".getBytes());
          byte[] data = new byte[1024];
          Arrays.fill(data, (byte) 'x');
          for (int j = 0; j < 100; j++) {
              data[1023] = Integer.valueOf(j).byteValue();
              lh.addEntry(data);
          }
          lh.close();
  
          LedgerHandle readLh = bkc.openLedger(lh.getId(), digestType, "".getBytes());
          LedgerEntry lastEntry = readLh.readLastEntry();
  
          assertEquals(lastEntry.getEntry()[1023], Integer.valueOf(99).byteValue());
  
          lh.close();
          readLh.close();
      }
  }
  