content: package org.apache.lucene.index;
  
  /**
   * 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.
   */
  
  
  /**
   * Class to write byte streams into slices of shared
   * byte[].  This is used by DocumentsWriter to hold the
   * posting list for many terms in RAM.
   */
  
  final class ByteSliceWriter {
  
    private byte[] slice;
    private int upto;
    private final ByteBlockPool pool;
  
    int offset0;
  
    public ByteSliceWriter(ByteBlockPool pool) {
      this.pool = pool;
    }
  
    /**
     * Set up the writer to write at address.
     */ 
    public void init(int address) {
      slice = pool.buffers[address >> DocumentsWriter.BYTE_BLOCK_SHIFT];
      assert slice != null;
      upto = address & DocumentsWriter.BYTE_BLOCK_MASK;
      offset0 = address;
      assert upto < slice.length;
    }
  
    /** Write byte into byte slice stream */
    public void writeByte(byte b) {
      assert slice != null;
      if (slice[upto] != 0) {
        upto = pool.allocSlice(slice, upto);
        slice = pool.buffer;
        offset0 = pool.byteOffset;
        assert slice != null;
      }
      slice[upto++] = b;
      assert upto != slice.length;
    }
  
    public void writeBytes(final byte[] b, int offset, final int len) {
      final int offsetEnd = offset + len;
      while(offset < offsetEnd) {
        if (slice[upto] != 0) {
          // End marker
          upto = pool.allocSlice(slice, upto);
          slice = pool.buffer;
          offset0 = pool.byteOffset;
        }
  
        slice[upto++] = b[offset++];
        assert upto != slice.length;
      }
    }
  
    public int getAddress() {
      return upto + (offset0 & DocumentsWriter.BYTE_BLOCK_NOT_MASK);
    }
  
    public void writeVInt(int i) {
      while ((i & ~0x7F) != 0) {
        writeByte((byte)((i & 0x7f) | 0x80));
        i >>>= 7;
      }
      writeByte((byte) i);
    }
  }
  