@Override
  public String toString() {
    return "[Tag type : " + this.type + ", value : "
      + ByteBufferUtils.toStringBinary(buffer, getValueOffset(), getValueLength()) + "]";
  }
This is a {@link Tag} implementation in which value is backed by {@link java.nio.ByteBuffer}
hbase-common/src/main/java/org/apache/hadoop/hbase/ByteBufferTag.java