public TScan setFilterString(byte[] filterString) {
    this.filterString = filterString == null ? (java.nio.ByteBuffer)null   : java.nio.ByteBuffer.wrap(filterString.clone());
    return this;
  }
Returns true if field timeRange is set (has been assigned a value) and false otherwise
hbase-thrift/src/main/java/org/apache/hadoop/hbase/thrift2/generated/TScan.java