public void init(Random r, SupportedTypes supportedTypes, int maxComplexDepth, boolean allowNull) {
    this.r = r;
    this.allowNull = allowNull;
    chooseSchema(supportedTypes, maxComplexDepth);
  }
Generate object inspector and random row object[].
serde/src/test/org/apache/hadoop/hive/serde2/SerdeRandomRowSource.java