Java Operations.concatenate方法代码示例

import org.apache.lucene.util.automaton.Operations; //导入方法依赖的package包/类
/**
 * Create a automaton for a given context query this automaton will be used
 * to find the matching paths with the fst
 *
 * @param preserveSep set an additional char (<code>XAnalyzingSuggester.SEP_LABEL</code>) between each context query
 * @param queries list of {@link ContextQuery} defining the lookup context
 *
 * @return Automaton matching the given Query
 */
public static Automaton toAutomaton(boolean preserveSep, Iterable<ContextQuery> queries) {
    Automaton a = Automata.makeEmptyString();

    Automaton gap = Automata.makeChar(ContextMapping.SEPARATOR);
    if (preserveSep) {
        // if separators are preserved the fst contains a SEP_LABEL
        // behind each gap. To have a matching automaton, we need to
        // include the SEP_LABEL in the query as well
        gap = Operations.concatenate(gap, Automata.makeChar(XAnalyzingSuggester.SEP_LABEL));
    }

    for (ContextQuery query : queries) {
        a = Operations.concatenate(Arrays.asList(query.toAutomaton(), gap, a));
    }

    // TODO: should we limit this?  Do any of our ContextQuery impls really create exponential regexps?  GeoQuery looks safe (union
    // of strings).
    return Operations.determinize(a, Integer.MAX_VALUE);
}
 

import org.apache.lucene.util.automaton.Operations; //导入方法依赖的package包/类
protected Automaton convertAutomaton(Automaton a) {
  if (queryPrefix != null) {
    a = Operations.concatenate(Arrays.asList(queryPrefix, a));
    // This automaton should not blow up during determinize:
    a = Operations.determinize(a, Integer.MAX_VALUE);
  }
  return a;
}
 

import org.apache.lucene.util.automaton.Operations; //导入方法依赖的package包/类
/** Return an {@link Automaton} that matches the given pattern. */
public static Automaton simpleMatchToAutomaton(String pattern) {
    List<Automaton> automata = new ArrayList<>();
    int previous = 0;
    for (int i = pattern.indexOf('*'); i != -1; i = pattern.indexOf('*', i + 1)) {
        automata.add(Automata.makeString(pattern.substring(previous, i)));
        automata.add(Automata.makeAnyString());
        previous = i + 1;
    }
    automata.add(Automata.makeString(pattern.substring(previous)));
    return Operations.concatenate(automata);
}
 

import org.apache.lucene.util.automaton.Operations; //导入方法依赖的package包/类
public void testEquals() {
  AutomatonQuery a1 = new AutomatonQuery(newTerm("foobar"), Automata
      .makeString("foobar"));
  // reference to a1
  AutomatonQuery a2 = a1;
  // same as a1 (accepts the same language, same term)
  AutomatonQuery a3 = new AutomatonQuery(newTerm("foobar"),
                          Operations.concatenate(
                               Automata.makeString("foo"),
                               Automata.makeString("bar")));
  // different than a1 (same term, but different language)
  AutomatonQuery a4 = new AutomatonQuery(newTerm("foobar"),
                                         Automata.makeString("different"));
  // different than a1 (different term, same language)
  AutomatonQuery a5 = new AutomatonQuery(newTerm("blah"),
                                         Automata.makeString("foobar"));
  
  assertEquals(a1.hashCode(), a2.hashCode());
  assertEquals(a1, a2);
  
  assertEquals(a1.hashCode(), a3.hashCode());
  assertEquals(a1, a3);

  // different class
  AutomatonQuery w1 = new WildcardQuery(newTerm("foobar"));
  // different class
  AutomatonQuery w2 = new RegexpQuery(newTerm("foobar"));
  
  assertFalse(a1.equals(w1));
  assertFalse(a1.equals(w2));
  assertFalse(w1.equals(w2));
  assertFalse(a1.equals(a4));
  assertFalse(a1.equals(a5));
  assertFalse(a1.equals(null));
}
 

import org.apache.lucene.util.automaton.Operations; //导入方法依赖的package包/类
/**
 * Test that rewriting to a prefix query works as expected, preserves
 * MultiTermQuery semantics.
 */
public void testRewritePrefix() throws IOException {
  Automaton pfx = Automata.makeString("do");
  Automaton prefixAutomaton = Operations.concatenate(pfx, Automata.makeAnyString());
  AutomatonQuery aq = new AutomatonQuery(newTerm("bogus"), prefixAutomaton);
  Terms terms = MultiFields.getTerms(searcher.getIndexReader(), FN);
  assertTrue(aq.getTermsEnum(terms) instanceof PrefixTermsEnum);
  assertEquals(3, automatonQueryNrHits(aq));
}
 

import org.apache.lucene.util.automaton.Operations; //导入方法依赖的package包/类
private Automaton join(String ... strings) {
  List<Automaton> as = new ArrayList<>();
  for(String s : strings) {
    as.add(s2a(s));
    as.add(SEP_A);
  }
  as.remove(as.size()-1);
  return Operations.concatenate(as);
}
 

import org.apache.lucene.util.automaton.Operations; //导入方法依赖的package包/类
public void testSynOverHole() throws Exception {

    final TokenStream ts = new CannedTokenStream(
      new Token[] {
        token("a", 1, 1),
        token("X", 0, 2),
        token("b", 2, 1),
      });
    final Automaton a1 = Operations.union(join(s2a("a"), SEP_A, HOLE_A), s2a("X"));
    final Automaton expected = Operations.concatenate(a1, join(SEP_A, s2a("b")));
    assertSameLanguage(expected, ts);
  }