LongArrayStream.java

package edu.berkeley.cs.succinct.util.stream;

import org.apache.hadoop.fs.FSDataInputStream;

import java.io.IOException;

/**
 * IntArray-like wrapper for FSDataInputStream
 */
public class LongArrayStream {
  int size;
  long startPos;
  FSDataInputStream stream;

  public LongArrayStream(FSDataInputStream stream, long startPos, int sizeInBytes) {
    this.stream = stream;
    this.startPos = startPos;
    this.size = sizeInBytes / 8;
  }

  public long get(int i) throws IOException {
    if (i < 0 || i >= size) {
      throw new ArrayIndexOutOfBoundsException("i = " + i + " size = " + size);
    }
    stream.seek(startPos + i * 8);
    return stream.readLong();
  }

  public void close() throws IOException {
    stream.close();
  }

  public int size() {
    return size;
  }

}