java/pig-galago/src/com/yahoo/pig/StandAloneParser.java

   1 /*
   2  * Copyright (c) 2007 Yahoo! Inc.  All rights reserved.
   3  * See accompanying LICENSE file.
   4  */
   5 package com.yahoo.pig;
   6
   7 import java.io.*;
   8 import java.util.*;
   9
  10 import com.yahoo.pig.impl.PigContext;
  11 import com.yahoo.pig.PigServer.ExecType;
  12 import com.yahoo.pig.impl.logicalLayer.LogicalPlan;
  13 import com.yahoo.pig.impl.logicalLayer.LogicalPlanBuilder;
  14 import com.yahoo.pig.impl.logicalLayer.parser.ParseException;
  15 import com.yahoo.pig.impl.logicalLayer.parser.QueryParser;
  16 import com.yahoo.pig.impl.physicalLayer.IntermedResult;
  17
  18 public class StandAloneParser {
  19     public static ClassLoader classloader = LogicalPlanBuilder.class.getClassLoader();
  20
  21     public static void main(String args[]) throws IOException {
  22
  23         Map<String, IntermedResult> aliases = new HashMap<String, IntermedResult>();
  24
  25         BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
  26
  27         while (true) {
  28             System.out.print("> ");
  29
  30             String line;
  31             try {
  32                 line = in.readLine();
  33             } catch (IOException e) {
  34                 e.printStackTrace();
  35                 return;
  36             }
  37
  38             if (line.toLowerCase().equals("quit")) break;
  39             if (line.toLowerCase().startsWith("#")) continue;
  40             else tryParse(line, aliases);
  41
  42         }
  43
  44     }
  45
  46     private static void tryParse(String query, Map<String, IntermedResult> aliases) {
  47         if (query.trim().equals(""))
  48                 return;
  49         ByteArrayInputStream in = new ByteArrayInputStream(query.getBytes());
  50         QueryParser parser = new QueryParser(in, new PigContext(ExecType.LOCAL), aliases);
  51         try {
  52             LogicalPlan lp = parser.Parse();
  53             System.out.println("--- Query parsed successfully ---");
  54             if (lp.alias != null) aliases.put(lp.alias, new IntermedResult(lp));
  55             System.out.print("Current aliases: ");
  56             for (Iterator<String> it = aliases.keySet().iterator(); it.hasNext(); ) {
  57                 String alias = it.next();
  58                 IntermedResult ir = aliases.get(alias);
  59                 System.out.print(alias + "->" + ir.lp.root().outputSchema());
  60                 if (it.hasNext()) System.out.print(", \n");
  61                 else System.out.print("\n");
  62             }
  63         } catch (ParseException e) {
  64             System.out.println("Parse error: " + e);
  65         }
  66     }
  67 }