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.distributedlog;
  
  import static org.junit.Assert.assertEquals;
  import static org.junit.Assert.assertFalse;
  import static org.junit.Assert.assertTrue;
  import static org.junit.Assert.fail;
  
  import java.util.Arrays;
  import org.apache.distributedlog.api.DistributedLogManager;
  import org.apache.distributedlog.exceptions.EndOfStreamException;
  import org.junit.Rule;
  import org.junit.Test;
  import org.junit.rules.TestName;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  
  /**
   * Test Case for {@link AppendOnlyStreamReader}.
   */
  public class TestAppendOnlyStreamReader extends TestDistributedLogBase {
      static final Logger LOG = LoggerFactory.getLogger(TestAppendOnlyStreamReader.class);
  
      @Rule
      public TestName testNames = new TestName();
  
      // Simple test subroutine writes some records, reads some back, skips ahead, skips back.
      public void skipForwardThenSkipBack(String name, DistributedLogConfiguration conf) throws Exception {
          DistributedLogManager dlmwrite = createNewDLM(conf, name);
          DistributedLogManager dlmreader = createNewDLM(conf, name);
  
          long txid = 1;
          AppendOnlyStreamWriter writer = dlmwrite.getAppendOnlyStreamWriter();
          writer.write(DLMTestUtil.repeatString("abc", 5).getBytes());
          writer.write(DLMTestUtil.repeatString("abc", 5).getBytes());
          writer.write(DLMTestUtil.repeatString("def", 5).getBytes());
          writer.write(DLMTestUtil.repeatString("def", 5).getBytes());
          writer.write(DLMTestUtil.repeatString("ghi", 5).getBytes());
          writer.write(DLMTestUtil.repeatString("ghi", 5).getBytes());
          writer.force(false);
          writer.close();
  
          AppendOnlyStreamReader reader = dlmreader.getAppendOnlyStreamReader();
          byte[] bytesIn = new byte[30];
  
          byte[] bytes1 = DLMTestUtil.repeatString("abc", 10).getBytes();
          byte[] bytes2 = DLMTestUtil.repeatString("def", 10).getBytes();
          byte[] bytes3 = DLMTestUtil.repeatString("ghi", 10).getBytes();
  
          int read = reader.read(bytesIn, 0, 30);
          assertEquals(30, read);
          assertTrue(Arrays.equals(bytes1, bytesIn));
  
          reader.skipTo(60);
          read = reader.read(bytesIn, 0, 30);
          assertEquals(30, read);
          assertTrue(Arrays.equals(bytes3, bytesIn));
  
          reader.skipTo(30);
          read = reader.read(bytesIn, 0, 30);
          assertEquals(30, read);
          assertTrue(Arrays.equals(bytes2, bytesIn));
      }
  
      @Test(timeout = 60000)
      public void testSkipToSkipsBytesWithImmediateFlush() throws Exception {
          String name = testNames.getMethodName();
  
          DistributedLogConfiguration confLocal = new DistributedLogConfiguration();
          confLocal.loadConf(conf);
          confLocal.setImmediateFlushEnabled(true);
          confLocal.setOutputBufferSize(0);
  
          skipForwardThenSkipBack(name, confLocal);
      }
  
      @Test(timeout = 60000)
      public void testSkipToSkipsBytesWithLargerLogRecords() throws Exception {
          String name = testNames.getMethodName();
  
          DistributedLogConfiguration confLocal = new DistributedLogConfiguration();
          confLocal.loadConf(conf);
          confLocal.setImmediateFlushEnabled(false);
          confLocal.setOutputBufferSize(1024 * 100);
          confLocal.setPeriodicFlushFrequencyMilliSeconds(1000 * 60);
  
          skipForwardThenSkipBack(name, confLocal);
      }
  
      @Test(timeout = 60000)
      public void testSkipToSkipsBytesUntilEndOfStream() throws Exception {
          String name = testNames.getMethodName();
  
          DistributedLogManager dlmwrite = createNewDLM(conf, name);
          DistributedLogManager dlmreader = createNewDLM(conf, name);
  
          long txid = 1;
          AppendOnlyStreamWriter writer = dlmwrite.getAppendOnlyStreamWriter();
          writer.write(DLMTestUtil.repeatString("abc", 5).getBytes());
          writer.markEndOfStream();
          writer.force(false);
          writer.close();
  
          AppendOnlyStreamReader reader = dlmreader.getAppendOnlyStreamReader();
          byte[] bytesIn = new byte[9];
  
          int read = reader.read(bytesIn, 0, 9);
          assertEquals(9, read);
          assertTrue(Arrays.equals(DLMTestUtil.repeatString("abc", 3).getBytes(), bytesIn));
  
          assertTrue(reader.skipTo(15));
  
          try {
              read = reader.read(bytesIn, 0, 1);
              fail("Should have thrown");
          } catch (EndOfStreamException ex) {
          }
  
          assertTrue(reader.skipTo(0));
  
          try {
              reader.skipTo(16);
              fail("Should have thrown");
          } catch (EndOfStreamException ex) {
          }
      }
  
      @Test(timeout = 60000)
      public void testSkipToreturnsFalseIfPositionDoesNotExistYetForUnSealedStream() throws Exception {
          String name = testNames.getMethodName();
  
          DistributedLogManager dlmwrite = createNewDLM(conf, name);
          DistributedLogManager dlmreader = createNewDLM(conf, name);
  
          long txid = 1;
          AppendOnlyStreamWriter writer = dlmwrite.getAppendOnlyStreamWriter();
          writer.write(DLMTestUtil.repeatString("abc", 5).getBytes());
          writer.close();
  
          final AppendOnlyStreamReader reader = dlmreader.getAppendOnlyStreamReader();
          byte[] bytesIn = new byte[9];
  
          int read = reader.read(bytesIn, 0, 9);
          assertEquals(9, read);
          assertTrue(Arrays.equals(DLMTestUtil.repeatString("abc", 3).getBytes(), bytesIn));
  
          assertFalse(reader.skipTo(16));
          assertFalse(reader.skipTo(16));
  
          AppendOnlyStreamWriter writer2 = dlmwrite.getAppendOnlyStreamWriter();
          writer2.write(DLMTestUtil.repeatString("abc", 5).getBytes());
          writer2.close();
  
          assertTrue(reader.skipTo(16));
  
          byte[] bytesIn2 = new byte[5];
          read = reader.read(bytesIn2, 0, 5);
          assertEquals(5, read);
          assertTrue(Arrays.equals("bcabc".getBytes(), bytesIn2));
      }
  
      @Test(timeout = 60000)
      public void testSkipToForNoPositionChange() throws Exception {
          String name = testNames.getMethodName();
  
          DistributedLogManager dlmwrite = createNewDLM(conf, name);
          DistributedLogManager dlmreader = createNewDLM(conf, name);
  
          long txid = 1;
          AppendOnlyStreamWriter writer = dlmwrite.getAppendOnlyStreamWriter();
          writer.write(DLMTestUtil.repeatString("abc", 5).getBytes());
          writer.close();
  
          final AppendOnlyStreamReader reader = dlmreader.getAppendOnlyStreamReader();
  
          assertTrue(reader.skipTo(0));
  
          byte[] bytesIn = new byte[4];
          int read = reader.read(bytesIn, 0, 4);
          assertEquals(4, read);
          assertEquals("abca", new String(bytesIn));
  
          assertTrue(reader.skipTo(reader.position()));
  
          assertTrue(reader.skipTo(1));
  
          read = reader.read(bytesIn, 0, 4);
          assertEquals(4, read);
          assertEquals("bcab", new String(bytesIn));
      }
  }
  