+++ /dev/null
-package org.apache.lucene.search;
-
-/**
- * Licensed to the Apache Software Foundation (ASF) under one or more
- * contributor license agreements. See the NOTICE file distributed with
- * this work for additional information regarding copyright ownership.
- * The ASF licenses this file to You under the Apache License, Version 2.0
- * (the "License"); you may not use this file except in compliance with
- * the License. You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-import java.io.IOException;
-
-import org.apache.lucene.index.IndexReader;
-import org.apache.lucene.index.Term;
-
-/**
- * Subclass of FilteredTermEnum for enumerating all terms that match the
- * specified wildcard filter term.
- * <p>
- * Term enumerations are always ordered by Term.compareTo(). Each term in
- * the enumeration is greater than all that precede it.
- */
-public class WildcardTermEnum extends FilteredTermEnum {
- final Term searchTerm;
- final String field;
- final String text;
- final String pre;
- final int preLen;
- boolean endEnum = false;
-
- /**
- * Creates a new <code>WildcardTermEnum</code>.
- * <p>
- * After calling the constructor the enumeration is already pointing to the first
- * valid term if such a term exists.
- */
- public WildcardTermEnum(IndexReader reader, Term term) throws IOException {
- super();
- searchTerm = term;
- field = searchTerm.field();
- final String searchTermText = searchTerm.text();
-
- final int sidx = searchTermText.indexOf(WILDCARD_STRING);
- final int cidx = searchTermText.indexOf(WILDCARD_CHAR);
- int idx = sidx;
- if (idx == -1) {
- idx = cidx;
- }
- else if (cidx >= 0) {
- idx = Math.min(idx, cidx);
- }
- pre = idx != -1?searchTerm.text().substring(0,idx): "";
-
- preLen = pre.length();
- text = searchTermText.substring(preLen);
- setEnum(reader.terms(new Term(searchTerm.field(), pre)));
- }
-
- @Override
- protected final boolean termCompare(Term term) {
- if (field == term.field()) {
- String searchText = term.text();
- if (searchText.startsWith(pre)) {
- return wildcardEquals(text, 0, searchText, preLen);
- }
- }
- endEnum = true;
- return false;
- }
-
- @Override
- public float difference() {
- return 1.0f;
- }
-
- @Override
- public final boolean endEnum() {
- return endEnum;
- }
-
- /********************************************
- * String equality with support for wildcards
- ********************************************/
-
- public static final char WILDCARD_STRING = '*';
- public static final char WILDCARD_CHAR = '?';
-
- /**
- * Determines if a word matches a wildcard pattern.
- * <small>Work released by Granta Design Ltd after originally being done on
- * company time.</small>
- */
- public static final boolean wildcardEquals(String pattern, int patternIdx,
- String string, int stringIdx)
- {
- int p = patternIdx;
-
- for (int s = stringIdx; ; ++p, ++s)
- {
- // End of string yet?
- boolean sEnd = (s >= string.length());
- // End of pattern yet?
- boolean pEnd = (p >= pattern.length());
-
- // If we're looking at the end of the string...
- if (sEnd)
- {
- // Assume the only thing left on the pattern is/are wildcards
- boolean justWildcardsLeft = true;
-
- // Current wildcard position
- int wildcardSearchPos = p;
- // While we haven't found the end of the pattern,
- // and haven't encountered any non-wildcard characters
- while (wildcardSearchPos < pattern.length() && justWildcardsLeft)
- {
- // Check the character at the current position
- char wildchar = pattern.charAt(wildcardSearchPos);
-
- // If it's not a wildcard character, then there is more
- // pattern information after this/these wildcards.
- if (wildchar != WILDCARD_CHAR && wildchar != WILDCARD_STRING)
- {
- justWildcardsLeft = false;
- }
- else
- {
- // to prevent "cat" matches "ca??"
- if (wildchar == WILDCARD_CHAR) {
- return false;
- }
-
- // Look at the next character
- wildcardSearchPos++;
- }
- }
-
- // This was a prefix wildcard search, and we've matched, so
- // return true.
- if (justWildcardsLeft)
- {
- return true;
- }
- }
-
- // If we've gone past the end of the string, or the pattern,
- // return false.
- if (sEnd || pEnd)
- {
- break;
- }
-
- // Match a single character, so continue.
- if (pattern.charAt(p) == WILDCARD_CHAR)
- {
- continue;
- }
-
- //
- if (pattern.charAt(p) == WILDCARD_STRING)
- {
- // Look at the character beyond the '*' characters.
- while (p < pattern.length() && pattern.charAt(p) == WILDCARD_STRING)
- ++p;
- // Examine the string, starting at the last character.
- for (int i = string.length(); i >= s; --i)
- {
- if (wildcardEquals(pattern, p, string, i))
- {
- return true;
- }
- }
- break;
- }
- if (pattern.charAt(p) != string.charAt(s))
- {
- break;
- }
- }
- return false;
- }
-}
fnp / pylucene.git / blobdiff