pylucene 3.5.0-3

[pylucene.git] / lucene-java-3.5.0 / lucene / contrib / analyzers / common / src / java / org / apache / lucene / analysis / pt / PortugueseStemmer.java

diff --git a/lucene-java-3.5.0/lucene/contrib/analyzers/common/src/java/org/apache/lucene/analysis/pt/PortugueseStemmer.java b/lucene-java-3.5.0/lucene/contrib/analyzers/common/src/java/org/apache/lucene/analysis/pt/PortugueseStemmer.java
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+++ b/lucene-java-3.5.0/lucene/contrib/analyzers/common/src/java/org/apache/lucene/analysis/pt/PortugueseStemmer.java
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+package org.apache.lucene.analysis.pt;
+
+/**
+ * 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.util.Map;
+
+/**
+ * Portuguese stemmer implementing the RSLP (Removedor de Sufixos da Lingua Portuguesa)
+ * algorithm. This is sometimes also referred to as the Orengo stemmer.
+ * 
+ * @see RSLPStemmerBase
+ */
+public class PortugueseStemmer extends RSLPStemmerBase {
+  private static final Step plural, feminine, adverb, augmentative, noun, verb, vowel;
+  
+  static {
+    Map<String,Step> steps = parse(PortugueseStemmer.class, "portuguese.rslp");
+    plural = steps.get("Plural");
+    feminine = steps.get("Feminine");
+    adverb = steps.get("Adverb");
+    augmentative = steps.get("Augmentative");
+    noun = steps.get("Noun");
+    verb = steps.get("Verb");
+    vowel = steps.get("Vowel");
+  }
+  
+  /**
+   * @param s buffer, oversized to at least <code>len+1</code>
+   * @param len initial valid length of buffer
+   * @return new valid length, stemmed
+   */
+  public int stem(char s[], int len) {
+    assert s.length >= len + 1 : "this stemmer requires an oversized array of at least 1";
+    
+    len = plural.apply(s, len);
+    len = adverb.apply(s, len);
+    len = feminine.apply(s, len);
+    len = augmentative.apply(s, len);
+    
+    int oldlen = len;
+    len = noun.apply(s, len);
+    
+    if (len == oldlen) { /* suffix not removed */
+      oldlen = len;
+      
+      len = verb.apply(s, len);
+      
+      if (len == oldlen) { /* suffix not removed */
+        len = vowel.apply(s, len);
+      }
+    }
+    
+    // rslp accent removal
+    for (int i = 0; i < len; i++) {
+      switch(s[i]) {
+        case 'à':
+        case 'á':
+        case 'â':
+        case 'ã':
+        case 'ä':
+        case 'å': s[i] = 'a'; break;
+        case 'ç': s[i] = 'c'; break;
+        case 'è':
+        case 'é':
+        case 'ê':
+        case 'ë': s[i] = 'e'; break;
+        case 'ì':
+        case 'í':
+        case 'î':
+        case 'ï': s[i] = 'i'; break;
+        case 'ñ': s[i] = 'n'; break;
+        case 'ò':
+        case 'ó':
+        case 'ô':
+        case 'õ':
+        case 'ö': s[i] = 'o'; break;
+        case 'ù':
+        case 'ú':
+        case 'û':
+        case 'ü': s[i] = 'u'; break;
+        case 'ý':
+        case 'ÿ': s[i] = 'y'; break;
+      }
+    }
+    return len;
+  }
+}