java/pig-galago/src/com/yahoo/pig/impl/logicalLayer/schema/SchemaField.java

   1 /*
   2  * Copyright (c) 2007 Yahoo! Inc.  All rights reserved.
   3  * See accompanying LICENSE file.
   4  */
   5 package com.yahoo.pig.impl.logicalLayer.schema;
   6
   7 import java.util.ArrayList;
   8 import java.util.List;
   9
  10
  11
  12
  13 /**
  14  * A SchemaField encapsulates a column alias
  15  * and its numeric column value.
  16  * @author dnm
  17  *
  18  */
  19 public class SchemaField extends SchemaItem {
  20     public Type type = Type.string;
  21
  22     public SchemaField(String alias) {
  23         this.alias = alias;
  24     }
  25     public Type getType() { return type; }
  26     public int colFor(String alias) {
  27         return -1;
  28     }
  29     public SchemaItem schemaFor(int col) {
  30         return null;
  31     }
  32
  33     public SchemaField copy(){
  34         return new SchemaField(alias);
  35     }
  36
  37     public List<SchemaItem> flatten(){
  38         List<SchemaItem> ret = new ArrayList<SchemaItem>();
  39         ret.add(this);
  40         return ret;
  41     }
  42 }