content: /*
   * The Alluxio Open Foundation licenses this work under the Apache License, version 2.0
   * (the "License"). You may not use this work except in compliance with the License, which is
   * available at www.apache.org/licenses/LICENSE-2.0
   *
   * This software is distributed on an "AS IS" basis, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND,
   * either express or implied, as more fully set forth in the License.
   *
   * See the NOTICE file distributed with this work for information regarding copyright ownership.
   */
  
  package alluxio.worker.block.io;
  
  import static org.junit.Assert.assertThrows;
  import static org.junit.Assert.assertTrue;
  
  import alluxio.exception.status.FailedPreconditionException;
  import alluxio.util.io.BufferUtils;
  
  import org.junit.Assert;
  import org.junit.Before;
  import org.junit.Rule;
  import org.junit.Test;
  import org.junit.rules.TemporaryFolder;
  
  import java.io.IOException;
  import java.nio.ByteBuffer;
  import java.nio.channels.ReadableByteChannel;
  
  /**
   * Tests for the {@link LocalFileBlockReader} class.
   */
  public class LocalFileBlockReaderTest {
    private static final long TEST_BLOCK_SIZE = 1024;
    private LocalFileBlockReader mReader;
  
    /** Rule to create a new temporary folder during each test. */
    @Rule
    public TemporaryFolder mFolder = new TemporaryFolder();
  
    /**
     * Sets up the file path and file block reader before a test runs.
     */
    @Before
    public void before() throws Exception {
      String testFilePath = mFolder.newFile().getAbsolutePath();
      byte[] buffer = BufferUtils.getIncreasingByteArray((int) TEST_BLOCK_SIZE);
      BufferUtils.writeBufferToFile(testFilePath, buffer);
      mReader = new LocalFileBlockReader(testFilePath);
    }
  
    /**
     * Test for the {@link LocalFileBlockReader#getChannel()} method.
     */
    @Test
    public void getChannel() throws Exception {
      ReadableByteChannel channel = mReader.getChannel();
      Assert.assertNotNull(channel);
      ByteBuffer buffer = ByteBuffer.allocate((int) TEST_BLOCK_SIZE);
      int bytesRead = channel.read(buffer);
      Assert.assertEquals(TEST_BLOCK_SIZE, bytesRead);
      assertTrue(BufferUtils.equalIncreasingByteBuffer(0, (int) TEST_BLOCK_SIZE, buffer));
    }
  
    @Test
    public void getLocation() {
      Assert.assertEquals(mReader.getFilePath(), mReader.getLocation());
    }
  
    /**
     * Test for the {@link LocalFileBlockReader#getLength()} method.
     */
    @Test
    public void getLength() {
      Assert.assertEquals(TEST_BLOCK_SIZE, mReader.getLength());
    }
  
    /**
     * Tests that an exception is thrown if the read exceeds the file length limit.
     */
    @Test
    public void readWithInvalidArgument() throws Exception {
      Exception e = assertThrows(IllegalArgumentException.class, () -> {
        mReader.read(TEST_BLOCK_SIZE - 1, 2);
      });
      assertTrue(e.getMessage().contains("exceeding fileSize"));
    }
  
    /**
     * Test for the {@link LocalFileBlockReader#read(long, long)} method.
     */
    @Test
    public void read() throws Exception {
      ByteBuffer buffer;
  
      // Read 1/4 block by setting the length to be 1/4 of the block size.
      buffer = mReader.read(0, TEST_BLOCK_SIZE / 4);
      assertTrue(BufferUtils.equalIncreasingByteBuffer(0, (int) TEST_BLOCK_SIZE / 4, buffer));
  
      // Read entire block by setting the length to be block size.
      buffer = mReader.read(0, TEST_BLOCK_SIZE);
      assertTrue(BufferUtils.equalIncreasingByteBuffer(0, (int) TEST_BLOCK_SIZE, buffer));
    }
  
    /**
     * Tests that a {@link FailedPreconditionException} is thrown when trying to read from a reader
     * after closing it.
     */
    @Test
    public void close() throws Exception {
      mReader.close();
      assertThrows(IOException.class, () -> {
        mReader.read(0, TEST_BLOCK_SIZE);
      });
    }
  }
  