hadoop DataInputByteBuffer 源码

  • 2022-10-20
  • 浏览 (218)

haddop DataInputByteBuffer 代码

文件路径:/hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/io/DataInputByteBuffer.java

/**
 * 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.io;

import java.io.DataInputStream;
import java.io.InputStream;
import java.nio.ByteBuffer;

public class DataInputByteBuffer extends DataInputStream {

  private static class Buffer extends InputStream {
    private final byte[] scratch = new byte[1];
    ByteBuffer[] buffers = new ByteBuffer[0];
    int bidx, pos, length;
    @Override
    public int read() {
      if (-1 == read(scratch, 0, 1)) {
        return -1;
      }
      return scratch[0] & 0xFF;
    }
    @Override
    public int read(byte[] b, int off, int len) {
      if (bidx >= buffers.length) {
        return -1;
      }
      int cur = 0;
      do {
        int rem = Math.min(len, buffers[bidx].remaining());
        buffers[bidx].get(b, off, rem);
        cur += rem;
        off += rem;
        len -= rem;
      } while (len > 0 && ++bidx < buffers.length);
      pos += cur;
      return cur;
    }
    public void reset(ByteBuffer[] buffers) {
      bidx = pos = length = 0;
      this.buffers = buffers;
      for (ByteBuffer b : buffers) {
        length += b.remaining();
      }
    }
    public int getPosition() {
      return pos;
    }
    public int getLength() {
      return length;
    }
    public ByteBuffer[] getData() {
      return buffers;
    }
  }

  private Buffer buffers;

  public DataInputByteBuffer() {
    this(new Buffer());
  }

  private DataInputByteBuffer(Buffer buffers) {
    super(buffers);
    this.buffers = buffers;
  }

  public void reset(ByteBuffer... input) {
    buffers.reset(input);
  }

  public ByteBuffer[] getData() {
    return buffers.getData();
  }

  public int getPosition() {
    return buffers.getPosition();
  }

  public int getLength() {
    return buffers.getLength();
  }
}

相关信息

hadoop 源码目录

相关文章

hadoop AbstractMapWritable 源码

hadoop ArrayFile 源码

hadoop ArrayPrimitiveWritable 源码

hadoop ArrayWritable 源码

hadoop BinaryComparable 源码

hadoop BloomMapFile 源码

hadoop BooleanWritable 源码

hadoop BoundedByteArrayOutputStream 源码

hadoop ByteBufferPool 源码

hadoop ByteWritable 源码

0  赞