src/com/sun/org/apache/bcel/internal/util/ByteSequence.java

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package com.sun.org.apache.bcel.internal.util;

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import java.io.*;

/**
 * Utility class that implements a sequence of bytes which can be read
 * via the `readByte()' method. This is used to implement a wrapper for the
 * Java byte code stream to gain some more readability.
 *
 * @author  <A HREF="mailto:markus.dahm@berlin.de">M. Dahm</A>
 */
public final class ByteSequence extends DataInputStream {
  private ByteArrayStream byte_stream;

  public ByteSequence(byte[] bytes) {
    super(new ByteArrayStream(bytes));
    byte_stream = (ByteArrayStream)in;
  }

  public final int getIndex()   { return byte_stream.getPosition(); }
  final  void      unreadByte() { byte_stream.unreadByte(); }

  private static final class ByteArrayStream extends ByteArrayInputStream {
    ByteArrayStream(byte[] bytes) { super(bytes); }
    final int  getPosition() { return pos; } // is protected in ByteArrayInputStream
    final void unreadByte()  { if(pos > 0) pos--; }
  }
}