nutchanalysis.java

nutch0.8源码

/* Generated By:JavaCC: Do not edit this line. NutchAnalysis.java */
package org.apache.nutch.analysis;

import java.io.StringReader;
import org.apache.hadoop.conf.Configuration;
import org.apache.nutch.searcher.Query;
import org.apache.nutch.searcher.QueryFilters;
import org.apache.nutch.searcher.Query.Clause;
import org.apache.nutch.util.NutchConfiguration;
import org.apache.lucene.analysis.Analyzer;
import org.apache.lucene.analysis.StopFilter;
import org.apache.lucene.analysis.TokenStream;

import java.io.*;
import java.util.*;

/** The JavaCC-generated Nutch lexical analyzer and query parser. */
public class NutchAnalysis implements NutchAnalysisConstants {

  private static final String[] STOP_WORDS = {
    "a", "and", "are", "as", "at", "be", "but", "by",
    "for", "if", "in", "into", "is", "it",
    "no", "not", "of", "on", "or", "s", "such",
    "t", "that", "the", "their", "then", "there", "these",
    "they", "this", "to", "was", "will", "with"
  };

  private static final Set STOP_SET = StopFilter.makeStopSet(STOP_WORDS);

  private Analyzer analyzer = null;
  private String queryString;
  private QueryFilters queryFilters;


  /** Constructs a nutch analysis. */
  public NutchAnalysis(String query, Analyzer analyzer) {
    this(new FastCharStream(new StringReader(query)));
    this.analyzer = analyzer;
  }

  /** True iff word is a stop word.  Stop words are only removed from queries.
   * Every word is indexed.  */
  public static boolean isStopWord(String word) {
    return STOP_SET.contains(word);
  }

  /** Construct a query parser for the text in a reader. */
  public static Query parseQuery(String queryString, Configuration conf) throws IOException {
    return parseQuery(queryString, null, conf);
  }

  /** Construct a query parser for the text in a reader. */
  public static Query parseQuery(String queryString, Analyzer analyzer, Configuration conf)
    throws IOException {
    NutchAnalysis parser = new NutchAnalysis(
          queryString, (analyzer != null) ? analyzer : new NutchDocumentAnalyzer(conf));
    parser.queryString = queryString;
    parser.queryFilters = new QueryFilters(conf);
    return parser.parse(conf);
  }

  /** For debugging. */
  public static void main(String[] args) throws Exception {
    BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
    while (true) {
      System.out.print("Query: ");
      String line = in.readLine();
      System.out.println(parseQuery(line, NutchConfiguration.create()));
    }
  }

/** Parse a query. */
  final public Query parse(Configuration conf) throws ParseException {
  Query query = new Query(conf);
  ArrayList terms;
  Token token;
  String field;
  boolean stop;
  boolean prohibited;
    nonOpOrTerm();
    label_1:
    while (true) {
      switch ((jj_ntk==-1)?jj_ntk():jj_ntk) {
      case WORD:
      case ACRONYM:
      case SIGRAM:
      case PLUS:
      case MINUS:
      case QUOTE:
        ;
        break;
      default:
        jj_la1[0] = jj_gen;
        break label_1;
      }
      stop=true; prohibited=false; field = Clause.DEFAULT_FIELD;
      switch ((jj_ntk==-1)?jj_ntk():jj_ntk) {
      case PLUS:
      case MINUS:
        switch ((jj_ntk==-1)?jj_ntk():jj_ntk) {
        case PLUS:
          jj_consume_token(PLUS);
              stop=false;
          break;
        case MINUS:
          jj_consume_token(MINUS);
                                        stop=false;prohibited=true;
          break;
        default:
          jj_la1[1] = jj_gen;
          jj_consume_token(-1);
          throw new ParseException();
        }
        break;
      default:
        jj_la1[2] = jj_gen;
        ;
      }
      if (jj_2_1(2147483647)) {
        token = jj_consume_token(WORD);
        jj_consume_token(COLON);
                             field = token.image;
      } else {
        ;
      }
      switch ((jj_ntk==-1)?jj_ntk():jj_ntk) {
      case QUOTE:
        terms = phrase(field);
                           stop=false;
        break;
      case WORD:
      case ACRONYM:
      case SIGRAM:
        // quoted terms or
              terms = compound(field);
        break;
      default:
        jj_la1[3] = jj_gen;
        jj_consume_token(-1);
        throw new ParseException();
      }
      nonOpOrTerm();
      String[] array = (String[])terms.toArray(new String[terms.size()]);

      if (stop
          && field == Clause.DEFAULT_FIELD
          && terms.size()==1
          && isStopWord(array[0])) {
        // ignore stop words only when single, unadorned terms in default field
      } else {
        if (prohibited)
          query.addProhibitedPhrase(array, field);
        else
          query.addRequiredPhrase(array, field);
      }
    }
    {if (true) return query;}
    throw new Error("Missing return statement in function");
  }

/** Parse an explcitly quoted phrase query.  Note that this may return a single
 * term, a trivial phrase.*/
  final public ArrayList phrase(String field) throws ParseException {
  int start;
  int end;
  ArrayList result = new ArrayList();
  String term;
    jj_consume_token(QUOTE);
    start = token.endColumn;
    label_2:
    while (true) {
      switch ((jj_ntk==-1)?jj_ntk():jj_ntk) {
      case PLUS:
      case MINUS:
      case COLON:
      case SLASH:
      case DOT:
      case ATSIGN:
      case APOSTROPHE:
      case WHITE:
        ;
        break;
      default:
        jj_la1[4] = jj_gen;
        break label_2;
      }
      nonTerm();
    }
    label_3:
    while (true) {
      switch ((jj_ntk==-1)?jj_ntk():jj_ntk) {
      case WORD:
      case ACRONYM:
      case SIGRAM:
        ;
        break;
      default:
        jj_la1[5] = jj_gen;
        break label_3;
      }
      term = term();
                    result.add(term);
      label_4:
      while (true) {
        switch ((jj_ntk==-1)?jj_ntk():jj_ntk) {
        case PLUS:
        case MINUS:
        case COLON:
        case SLASH:
        case DOT:
        case ATSIGN:
        case APOSTROPHE:
        case WHITE:
          ;
          break;
        default:
          jj_la1[6] = jj_gen;
          break label_4;
        }
        nonTerm();
      }
    }
    end = token.endColumn;
    switch ((jj_ntk==-1)?jj_ntk():jj_ntk) {
    case QUOTE:
      jj_consume_token(QUOTE);
      break;
    case 0:
      jj_consume_token(0);
      break;
    default:
      jj_la1[7] = jj_gen;
      jj_consume_token(-1);
      throw new ParseException();
    }
    if (this.queryFilters.isRawField(field)) {
      result.clear();
      result.add(queryString.substring(start, end));
    }
    {if (true) return result;}
    throw new Error("Missing return statement in function");
  }

/** Parse a compound term that is interpreted as an implicit phrase query.
 * Compounds are a sequence of terms separated by infix characters.  Note that
 * htis may return a single term, a trivial compound. */
  final public ArrayList compound(String field) throws ParseException {
  int start;
  ArrayList result = new ArrayList();
  String term;
  StringBuffer terms = new StringBuffer();
    start = token.endColumn;
    term = term();
    terms.append(term).append(" ");
    //result.add(term);

    label_5:
    while (true) {
      if (jj_2_2(2147483647)) {
        ;
      } else {
        break label_5;
      }
      label_6:
      while (true) {
        infix();
        switch ((jj_ntk==-1)?jj_ntk():jj_ntk) {
        case PLUS:
        case MINUS:
        case COLON:
        case SLASH:
        case DOT:
        case ATSIGN:
        case APOSTROPHE:
          ;
          break;
        default:
          jj_la1[8] = jj_gen;
          break label_6;
        }
      }
      term = term();
      terms.append(term).append(" ");
      //result.add(term);

    }
    if (this.queryFilters.isRawField(field)) {
//      result.clear();
      result.add(queryString.substring(start, token.endColumn));

    } else {
      org.apache.lucene.analysis.Token token;
      TokenStream tokens = analyzer.tokenStream(
                              field, new StringReader(terms.toString()));

      while (true) {
        try {
          token = tokens.next();
        } catch (IOException e) {
          token = null;
        }
        if (token == null) { break; }
        result.add(token.termText());
      }
      try {
        tokens.close();
      } catch (IOException e) {
        // ignore
      }
    }
    {if (true) return result;}
    throw new Error("Missing return statement in function");
  }

/** Parse a single term. */
  final public String term() throws ParseException {
  Token token;
    switch ((jj_ntk==-1)?jj_ntk():jj_ntk) {
    case WORD:
      token = jj_consume_token(WORD);
      break;
    case ACRONYM:
      token = jj_consume_token(ACRONYM);
      break;
    case SIGRAM:
      token = jj_consume_token(SIGRAM);
      break;
    default:
      jj_la1[9] = jj_gen;
      jj_consume_token(-1);
      throw new ParseException();
    }
    {if (true) return token.image;}
    throw new Error("Missing return statement in function");
  }

/** Parse anything but a term or a quote. */
  final public void nonTerm() throws ParseException {
    switch ((jj_ntk==-1)?jj_ntk():jj_ntk) {
    case WHITE:
      jj_consume_token(WHITE);
      break;
    case PLUS:
    case MINUS:
    case COLON:
    case SLASH:
    case DOT:
    case ATSIGN:
    case APOSTROPHE:
      infix();
      break;
    default:
      jj_la1[10] = jj_gen;
      jj_consume_token(-1);
      throw new ParseException();
    }
  }

  final public void nonTermOrEOF() throws ParseException {
    switch ((jj_ntk==-1)?jj_ntk():jj_ntk) {
    case PLUS:
    case MINUS:
    case COLON:
    case SLASH:
    case DOT:
    case ATSIGN:
    case APOSTROPHE:
    case WHITE:
      nonTerm();
      break;
    case 0:
      jj_consume_token(0);
      break;
    default:
      jj_la1[11] = jj_gen;
      jj_consume_token(-1);
      throw new ParseException();
    }
  }

/** Parse anything but a term or an operator (plur or minus or quote). */
  final public void nonOpOrTerm() throws ParseException {
    label_7:
    while (true) {
      if (jj_2_3(2)) {
        ;
      } else {
        break label_7;
      }
      switch ((jj_ntk==-1)?jj_ntk():jj_ntk) {
      case WHITE:
        jj_consume_token(WHITE);
        break;
      case COLON:
      case SLASH:
      case DOT:
      case ATSIGN:
      case APOSTROPHE:
        nonOpInfix();
        break;
      case PLUS:
      case MINUS:
        switch ((jj_ntk==-1)?jj_ntk():jj_ntk) {
        case PLUS:
          jj_consume_token(PLUS);
          break;
        case MINUS:
          jj_consume_token(MINUS);
          break;
        default:
          jj_la1[12] = jj_gen;
          jj_consume_token(-1);
          throw new ParseException();
        }
        nonTermOrEOF();
        break;
      default:
        jj_la1[13] = jj_gen;
        jj_consume_token(-1);
        throw new ParseException();
      }
    }
  }

/** Characters which can be used to form compound terms. */
  final public void infix() throws ParseException {
    switch ((jj_ntk==-1)?jj_ntk():jj_ntk) {
    case PLUS:
      jj_consume_token(PLUS);
      break;
    case MINUS:
      jj_consume_token(MINUS);
      break;
    case COLON:
    case SLASH:
    case DOT:
    case ATSIGN:
    case APOSTROPHE:
      nonOpInfix();
      break;
    default:
      jj_la1[14] = jj_gen;
      jj_consume_token(-1);
      throw new ParseException();
    }
  }

/** Parse infix characters except plus and minus. */
  final public void nonOpInfix() throws ParseException {
    switch ((jj_ntk==-1)?jj_ntk():jj_ntk) {
    case COLON:
      jj_consume_token(COLON);
      break;
    case SLASH:
      jj_consume_token(SLASH);
      break;
    case DOT:
      jj_consume_token(DOT);
      break;
    case ATSIGN:
      jj_consume_token(ATSIGN);
      break;
    case APOSTROPHE:
      jj_consume_token(APOSTROPHE);
      break;
    default:
      jj_la1[15] = jj_gen;
      jj_consume_token(-1);
      throw new ParseException();
    }
  }

  final private boolean jj_2_1(int xla) {
    jj_la = xla; jj_lastpos = jj_scanpos = token;