| /** |
| * 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.hbase.io; |
| |
| import java.io.InputStream; |
| |
| import org.apache.hadoop.hbase.nio.ByteBuff; |
| import org.apache.yetus.audience.InterfaceAudience; |
| |
| /** |
| * Not thread safe! |
| * <p> |
| * Please note that the reads will cause position movement on wrapped ByteBuff. |
| */ |
| @InterfaceAudience.Private |
| public class ByteBuffInputStream extends InputStream { |
| |
| private ByteBuff buf; |
| |
| public ByteBuffInputStream(ByteBuff buf) { |
| this.buf = buf; |
| } |
| |
| /** |
| * Reads the next byte of data from this input stream. The value byte is returned as an |
| * <code>int</code> in the range <code>0</code> to <code>255</code>. If no byte is available |
| * because the end of the stream has been reached, the value <code>-1</code> is returned. |
| * @return the next byte of data, or <code>-1</code> if the end of the stream has been reached. |
| */ |
| @Override |
| public int read() { |
| if (this.buf.hasRemaining()) { |
| return (this.buf.get() & 0xff); |
| } |
| return -1; |
| } |
| |
| /** |
| * Reads up to next <code>len</code> bytes of data from buffer into passed array(starting from |
| * given offset). |
| * @param b the array into which the data is read. |
| * @param off the start offset in the destination array <code>b</code> |
| * @param len the maximum number of bytes to read. |
| * @return the total number of bytes actually read into the buffer, or <code>-1</code> if not even |
| * 1 byte can be read because the end of the stream has been reached. |
| */ |
| @Override |
| public int read (byte b[], int off, int len) { |
| int avail = available(); |
| if (avail <= 0) { |
| return -1; |
| } |
| if (len <= 0) { |
| return 0; |
| } |
| |
| if (len > avail) { |
| len = avail; |
| } |
| this.buf.get(b, off, len); |
| return len; |
| } |
| |
| /** |
| * Skips <code>n</code> bytes of input from this input stream. Fewer bytes might be skipped if the |
| * end of the input stream is reached. The actual number <code>k</code> of bytes to be skipped is |
| * equal to the smaller of <code>n</code> and remaining bytes in the stream. |
| * @param n the number of bytes to be skipped. |
| * @return the actual number of bytes skipped. |
| */ |
| @Override |
| public long skip(long n) { |
| long k = Math.min(n, available()); |
| if (k <= 0) { |
| return 0; |
| } |
| this.buf.skip((int) k); |
| return k; |
| } |
| |
| /** |
| * @return the number of remaining bytes that can be read (or skipped |
| * over) from this input stream. |
| */ |
| @Override |
| public int available() { |
| return this.buf.remaining(); |
| } |
| } |