HDFS-7988. Replace usage of ExactSizeInputStream with LimitInputStream. Contributed by Walter Su.

hadoop-hdfs-project/hadoop-hdfs-client/src/main/java/org/apache/hadoop/hdfs/protocolPB/PBHelperClient.java

@@ -158,12 +158,12 @@ import org.apache.hadoop.hdfs.server.protocol.DatanodeStorageReport;
 import org.apache.hadoop.hdfs.server.protocol.StorageReport;
 import org.apache.hadoop.hdfs.shortcircuit.ShortCircuitShm.ShmId;
 import org.apache.hadoop.hdfs.shortcircuit.ShortCircuitShm.SlotId;
-import org.apache.hadoop.hdfs.util.ExactSizeInputStream;
 import org.apache.hadoop.io.EnumSetWritable;
 import org.apache.hadoop.io.Text;
 import org.apache.hadoop.security.proto.SecurityProtos.TokenProto;
 import org.apache.hadoop.security.token.Token;
 import org.apache.hadoop.util.DataChecksum;
+import org.apache.hadoop.util.LimitInputStream;
 
 /**
  * Utilities for converting protobuf classes to and from hdfs-client side
@@ -396,7 +396,7 @@ public class PBHelperClient {
 
     int size = CodedInputStream.readRawVarint32(firstByte, input);
     assert size >= 0;
-    return new ExactSizeInputStream(input, size);
+    return new LimitInputStream(input, size);
   }
 
   public static CipherOption convert(HdfsProtos.CipherOptionProto proto) {

hadoop-hdfs-project/hadoop-hdfs-client/src/main/java/org/apache/hadoop/hdfs/util/ExactSizeInputStream.java

@@ -1,127 +0,0 @@
-/**
- * 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.hdfs.util;
-
-import java.io.EOFException;
-import java.io.FilterInputStream;
-import java.io.IOException;
-import java.io.InputStream;
-
-import org.apache.hadoop.classification.InterfaceAudience;
-import org.apache.hadoop.classification.InterfaceStability;
-
-import com.google.common.base.Preconditions;
-
-import javax.annotation.Nonnull;
-
-/**
- * An InputStream implementations which reads from some other InputStream
- * but expects an exact number of bytes. Any attempts to read past the
- * specified number of bytes will return as if the end of the stream
- * was reached. If the end of the underlying stream is reached prior to
- * the specified number of bytes, an EOFException is thrown.
- */
-@InterfaceAudience.Private
-@InterfaceStability.Evolving
-public class ExactSizeInputStream extends FilterInputStream {
-  private int remaining;
-
-  /**
-   * Construct an input stream that will read no more than
-   * 'numBytes' bytes.
-   *
-   * If an EOF occurs on the underlying stream before numBytes
-   * bytes have been read, an EOFException will be thrown.
-   *
-   * @param in the inputstream to wrap
-   * @param numBytes the number of bytes to read
-   */
-  public ExactSizeInputStream(InputStream in, int numBytes) {
-    super(in);
-    Preconditions.checkArgument(numBytes >= 0,
-        "Negative expected bytes: ", numBytes);
-    this.remaining = numBytes;
-  }
-
-  @Override
-  public int available() throws IOException {
-    return Math.min(super.available(), remaining);
-  }
-
-  @Override
-  public int read() throws IOException {
-    // EOF if we reached our limit
-    if (remaining <= 0) {
-      return -1;
-    }
-    final int result = super.read();
-    if (result >= 0) {
-      --remaining;
-    } else if (remaining > 0) {
-      // Underlying stream reached EOF but we haven't read the expected
-      // number of bytes.
-      throw new EOFException(
-          "Premature EOF. Expected " + remaining + "more bytes");
-    }
-    return result;
-  }
-
-  @Override
-  public int read(@Nonnull final byte[] b, final int off, int len)
-                  throws IOException {
-    if (remaining <= 0) {
-      return -1;
-    }
-    len = Math.min(len, remaining);
-    final int result = super.read(b, off, len);
-    if (result >= 0) {
-      remaining -= result;
-    } else if (remaining > 0) {
-      // Underlying stream reached EOF but we haven't read the expected
-      // number of bytes.
-      throw new EOFException(
-          "Premature EOF. Expected " + remaining + "more bytes");
-    }
-    return result;
-  }
-
-  @Override
-  public long skip(final long n) throws IOException {
-    final long result = super.skip(Math.min(n, remaining));
-    if (result > 0) {
-      remaining -= result;
-    } else if (remaining > 0) {
-      // Underlying stream reached EOF but we haven't read the expected
-      // number of bytes.
-      throw new EOFException(
-          "Premature EOF. Expected " + remaining + "more bytes");
-    }
-    return result;
-  }
-
-  @Override
-  public boolean markSupported() {
-    return false;
-  }
-
-  @Override
-  public void mark(int readlimit) {
-    throw new UnsupportedOperationException();
-  }
-
-}

hadoop-hdfs-project/hadoop-hdfs-client/src/test/java/org/apache/hadoop/hdfs/util/TestExactSizeInputStream.java

@@ -1,129 +0,0 @@
-/**
- * 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.hdfs.util;
-
-import static org.junit.Assert.assertEquals;
-import static org.junit.Assert.assertFalse;
-import static org.junit.Assert.fail;
-
-import java.io.ByteArrayInputStream;
-import java.io.EOFException;
-import java.io.IOException;
-import java.io.InputStream;
-
-import org.junit.Test;
-
-public class TestExactSizeInputStream {
-  @Test
-  public void testBasicsReadSingle() throws IOException {
-    ExactSizeInputStream s = new ExactSizeInputStream(byteStream("hello"), 3);
-    assertEquals(3, s.available());
-    
-    assertEquals((int)'h', s.read());
-    assertEquals((int)'e', s.read());
-    assertEquals((int)'l', s.read());
-    assertEquals(-1, s.read());
-    assertEquals(0, s.available());
-  }
-  
-  @Test
-  public void testBasicsReadArray() throws IOException {
-    ExactSizeInputStream s = new ExactSizeInputStream(byteStream("hello"), 3);
-    assertEquals(3, s.available());
-    
-    byte[] buf = new byte[10];
-    
-    assertEquals(2, s.read(buf, 0, 2));
-    assertEquals('h', buf[0]);
-    assertEquals('e', buf[1]);
-    
-    assertEquals(1, s.read(buf, 0, 2));
-    assertEquals('l', buf[0]);
-    
-    assertEquals(-1, s.read(buf, 0, 2));
-  }
-  
-  @Test
-  public void testBasicsSkip() throws IOException {
-    ExactSizeInputStream s = new ExactSizeInputStream(byteStream("hello"), 3);
-    assertEquals(3, s.available());
-    
-    assertEquals(2, s.skip(2));
-    assertEquals(1, s.skip(2));
-    assertEquals(0, s.skip(2));
-  }
-  
-  @Test
-  public void testReadNotEnough() throws IOException {
-    // Ask for 5 bytes, only has 2
-    ExactSizeInputStream s = new ExactSizeInputStream(byteStream("he"), 5);
-    assertEquals(2, s.available());
-    
-    assertEquals((int)'h', s.read());
-    assertEquals((int)'e', s.read());
-    try {
-      s.read();
-      fail("Read when should be out of data");
-    } catch (EOFException e) {
-      // expected
-    }
-  }
-  
-  @Test
-  public void testSkipNotEnough() throws IOException {
-    // Ask for 5 bytes, only has 2
-    ExactSizeInputStream s = new ExactSizeInputStream(byteStream("he"), 5);
-    assertEquals(2, s.skip(3));
-    try {
-      s.skip(1);
-      fail("Skip when should be out of data");
-    } catch (EOFException e) {
-      // expected
-    }
-  }
-  
-  @Test
-  public void testReadArrayNotEnough() throws IOException {
-    // Ask for 5 bytes, only has 2
-    ExactSizeInputStream s = new ExactSizeInputStream(byteStream("he"), 5);
-    byte[] buf = new byte[10];
-    assertEquals(2, s.read(buf, 0, 5));
-    try {
-      s.read(buf, 2, 3);
-      fail("Read buf when should be out of data");
-    } catch (EOFException e) {
-      // expected
-    }
-  }
-
-  @Test
-  public void testMark() throws IOException {
-    ExactSizeInputStream s = new ExactSizeInputStream(byteStream("he"), 5);
-    assertFalse(s.markSupported());
-    try {
-      s.mark(1);
-      fail("Mark should not succeed");
-    } catch (UnsupportedOperationException uoe) {
-      // expected
-    }
-  }
-  
-  private static InputStream byteStream(String data) {
-    return new ByteArrayInputStream(data.getBytes());
-  }
-}

hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt

@@ -808,6 +808,9 @@ Release 2.8.0 - UNRELEASED
 
     HDFS-9153. Pretty-format the output for DFSIO. (Kai Zheng via wheat9)
 
+    HDFS-7988. Replace usage of ExactSizeInputStream with LimitInputStream.
+    (Walter Su via wheat9)
+
   OPTIMIZATIONS
 
     HDFS-8026. Trace FSOutputSummer#writeChecksumChunks rather than