pylucene 3.5.0-3

[pylucene.git] / lucene-java-3.5.0 / lucene / contrib / queryparser / src / java / org / apache / lucene / queryParser / surround / query / SrndTruncQuery.java

diff --git a/lucene-java-3.5.0/lucene/contrib/queryparser/src/java/org/apache/lucene/queryParser/surround/query/SrndTruncQuery.java b/lucene-java-3.5.0/lucene/contrib/queryparser/src/java/org/apache/lucene/queryParser/surround/query/SrndTruncQuery.java
new file mode 100644 (file)
index 0000000..4f28101
--- /dev/null
+++ b/lucene-java-3.5.0/lucene/contrib/queryparser/src/java/org/apache/lucene/queryParser/surround/query/SrndTruncQuery.java
@@ -0,0 +1,109 @@
+package org.apache.lucene.queryParser.surround.query;
+/**
+ * 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 org.apache.lucene.index.Term;
+import org.apache.lucene.index.TermEnum;
+import org.apache.lucene.index.IndexReader;
+
+import java.io.IOException;
+
+import java.util.regex.Pattern;
+import java.util.regex.Matcher;
+
+
+public class SrndTruncQuery extends SimpleTerm {
+  public SrndTruncQuery(String truncated, char unlimited, char mask) {
+    super(false); /* not quoted */
+    this.truncated = truncated;
+    this.unlimited = unlimited;
+    this.mask = mask;
+    truncatedToPrefixAndPattern();
+  }
+  
+  private final String truncated;
+  private final char unlimited;
+  private final char mask;
+  
+  private String prefix;
+  private Pattern pattern;
+  
+  
+  public String getTruncated() {return truncated;}
+  
+  @Override
+  public String toStringUnquoted() {return getTruncated();}
+
+  
+  protected boolean matchingChar(char c) {
+    return (c != unlimited) && (c != mask);
+  }
+
+  protected void appendRegExpForChar(char c, StringBuilder re) {
+    if (c == unlimited)
+      re.append(".*");
+    else if (c == mask)
+      re.append(".");
+    else
+      re.append(c);
+  }
+  
+  protected void truncatedToPrefixAndPattern() {
+    int i = 0;
+    while ((i < truncated.length()) && matchingChar(truncated.charAt(i))) {
+      i++;
+    }
+    prefix = truncated.substring(0, i);
+    
+    StringBuilder re = new StringBuilder();
+    while (i < truncated.length()) {
+      appendRegExpForChar(truncated.charAt(i), re);
+      i++;
+    }
+    pattern = Pattern.compile(re.toString());
+  }
+  
+  @Override
+  public void visitMatchingTerms(
+    IndexReader reader,
+    String fieldName,
+    MatchingTermVisitor mtv) throws IOException
+  {
+    int prefixLength = prefix.length();
+    TermEnum enumerator = reader.terms(new Term(fieldName, prefix));
+    Matcher matcher = pattern.matcher("");
+    try {
+      do {
+        Term term = enumerator.term();
+        if (term != null) {
+          String text = term.text();
+          if ((! text.startsWith(prefix)) || (! term.field().equals(fieldName))) {
+            break;
+          } else {
+            matcher.reset( text.substring(prefixLength));
+            if (matcher.matches()) {
+              mtv.visitMatchingTerm(term);
+            }
+          }
+        }
+      } while (enumerator.next());
+    } finally {
+      enumerator.close();
+      matcher.reset();
+    }
+  }
+}