content: package org.apache.lucene.analysis.fr;
  
  /**
   * 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.
   */
  
  /**
   * A stemmer for French words. 
   * <p>
   * The algorithm is based on the work of
   * Dr Martin Porter on his snowball project<br>
   * refer to http://snowball.sourceforge.net/french/stemmer.html<br>
   * (French stemming algorithm) for details
   * </p>
   * @deprecated Use {@link org.tartarus.snowball.ext.FrenchStemmer} instead, 
   * which has the same functionality. This filter will be removed in Lucene 5.0
   */
  @Deprecated
  public class FrenchStemmer {
  
      /**
       * Buffer for the terms while stemming them.
       */
      private StringBuilder sb = new StringBuilder();
  
      /**
       * A temporary buffer, used to reconstruct R2
       */
       private StringBuilder tb = new StringBuilder();
  
  	/**
  	 * Region R0 is equal to the whole buffer
  	 */
  	private String R0;
  
  	/**
  	 * Region RV
  	 * "If the word begins with two vowels, RV is the region after the third letter,
  	 * otherwise the region after the first vowel not at the beginning of the word,
  	 * or the end of the word if these positions cannot be found."
  	 */
      private String RV;
  
  	/**
  	 * Region R1
  	 * "R1 is the region after the first non-vowel following a vowel
  	 * or is the null region at the end of the word if there is no such non-vowel"
  	 */
      private String R1;
  
  	/**
  	 * Region R2
  	 * "R2 is the region after the first non-vowel in R1 following a vowel
  	 * or is the null region at the end of the word if there is no such non-vowel"
  	 */
      private String R2;
  
  
  	/**
  	 * Set to true if we need to perform step 2
  	 */
      private boolean suite;
  
  	/**
  	 * Set to true if the buffer was modified
  	 */
      private boolean modified;
  
  
      /**
       * Stems the given term to a unique <tt>discriminator</tt>.
       *
       * @param term  java.langString The term that should be stemmed
       * @return java.lang.String  Discriminator for <tt>term</tt>
       */
      protected String stem( String term ) {
  		if ( !isStemmable( term ) ) {
  			return term;
  		}
  
  		// Use lowercase for medium stemming.
  		term = term.toLowerCase();
  
  		// Reset the StringBuilder.
  		sb.delete( 0, sb.length() );
  		sb.insert( 0, term );
  
  		// reset the booleans
  		modified = false;
  		suite = false;
  
  		sb = treatVowels( sb );
  
  		setStrings();
  
  		step1();
  
  		if (!modified || suite)
  		{
  			if (RV != null)
  			{
  				suite = step2a();
  				if (!suite)
  					step2b();
  			}
  		}
  
  		if (modified || suite)
  			step3();
  		else
  			step4();
  
  		step5();
  
  		step6();
  
  		return sb.toString();
      }
  
  	/**
  	 * Sets the search region Strings<br>
  	 * it needs to be done each time the buffer was modified
  	 */
  	private void setStrings() {
  		// set the strings
  		R0 = sb.toString();
  		RV = retrieveRV( sb );
  		R1 = retrieveR( sb );
  		if ( R1 != null )
  		{
  			tb.delete( 0, tb.length() );
  			tb.insert( 0, R1 );
  			R2 = retrieveR( tb );
  		}
  		else
  			R2 = null;
  	}
  
  	/**
  	 * First step of the Porter Algorithm<br>
  	 * refer to http://snowball.sourceforge.net/french/stemmer.html for an explanation
  	 */
  	private void step1( ) {
  		String[] suffix = { "ances", "iqUes", "ismes", "ables", "istes", "ance", "iqUe", "isme", "able", "iste" };
  		deleteFrom( R2, suffix );
  
  		replaceFrom( R2, new String[] { "logies", "logie" }, "log" );
  		replaceFrom( R2, new String[] { "usions", "utions", "usion", "ution" }, "u" );
  		replaceFrom( R2, new String[] { "ences", "ence" }, "ent" );
  
  		String[] search = { "atrices", "ateurs", "ations", "atrice", "ateur", "ation"};
  		deleteButSuffixFromElseReplace( R2, search, "ic",  true, R0, "iqU" );
  
  		deleteButSuffixFromElseReplace( R2, new String[] { "ements", "ement" }, "eus", false, R0, "eux" );
  		deleteButSuffixFrom( R2, new String[] { "ements", "ement" }, "ativ", false );
  		deleteButSuffixFrom( R2, new String[] { "ements", "ement" }, "iv", false );
  		deleteButSuffixFrom( R2, new String[] { "ements", "ement" }, "abl", false );
  		deleteButSuffixFrom( R2, new String[] { "ements", "ement" }, "iqU", false );
  
  		deleteFromIfTestVowelBeforeIn( R1, new String[] { "issements", "issement" }, false, R0 );
  		deleteFrom( RV, new String[] { "ements", "ement" } );
  
  		deleteButSuffixFromElseReplace( R2, new String[] { "ités", "ité" }, "abil", false, R0, "abl" );
  		deleteButSuffixFromElseReplace( R2, new String[] { "ités", "ité" }, "ic", false, R0, "iqU" );
  		deleteButSuffixFrom( R2, new String[] { "ités", "ité" }, "iv", true );
  
  		String[] autre = { "ifs", "ives", "if", "ive" };
  		deleteButSuffixFromElseReplace( R2, autre, "icat", false, R0, "iqU" );
  		deleteButSuffixFromElseReplace( R2, autre, "at", true, R2, "iqU" );
  
  		replaceFrom( R0, new String[] { "eaux" }, "eau" );
  
  		replaceFrom( R1, new String[] { "aux" }, "al" );
  
  		deleteButSuffixFromElseReplace( R2, new String[] { "euses", "euse" }, "", true, R1, "eux" );
  
  		deleteFrom( R2, new String[] { "eux" } );
  
  		// if one of the next steps is performed, we will need to perform step2a
  		boolean temp = false;
  		temp = replaceFrom( RV, new String[] { "amment" }, "ant" );
  		if (temp == true)
  			suite = true;
  		temp = replaceFrom( RV, new String[] { "emment" }, "ent" );
  		if (temp == true)
  			suite = true;
  		temp = deleteFromIfTestVowelBeforeIn( RV, new String[] { "ments", "ment" }, true, RV );
  		if (temp == true)
  			suite = true;
  
  	}
  
  	/**
  	 * Second step (A) of the Porter Algorithm<br>
  	 * Will be performed if nothing changed from the first step
  	 * or changed were done in the amment, emment, ments or ment suffixes<br>
  	 * refer to http://snowball.sourceforge.net/french/stemmer.html for an explanation
  	 *
  	 * @return boolean - true if something changed in the StringBuilder
  	 */
  	private boolean step2a() {
  		String[] search = { "îmes", "îtes", "iraIent", "irait", "irais", "irai", "iras", "ira",
  							"irent", "iriez", "irez", "irions", "irons", "iront",
  							"issaIent", "issais", "issantes", "issante", "issants", "issant",
  							"issait", "issais", "issions", "issons", "issiez", "issez", "issent",
  							"isses", "isse", "ir", "is", "ît", "it", "ies", "ie", "i" };
  		return deleteFromIfTestVowelBeforeIn( RV, search, false, RV );
  	}
  
  	/**
  	 * Second step (B) of the Porter Algorithm<br>
  	 * Will be performed if step 2 A was performed unsuccessfully<br>
  	 * refer to http://snowball.sourceforge.net/french/stemmer.html for an explanation
  	 */
  	private void step2b() {
  		String[] suffix = { "eraIent", "erais", "erait", "erai", "eras", "erions", "eriez",
  							"erons", "eront","erez", "èrent", "era", "ées", "iez",
  							"ée", "és", "er", "ez", "é" };
  		deleteFrom( RV, suffix );
  
  		String[] search = { "assions", "assiez", "assent", "asses", "asse", "aIent",
  							"antes", "aIent", "Aient", "ante", "âmes", "âtes", "ants", "ant",
  							"ait", "aît", "ais", "Ait", "Aît", "Ais", "ât", "as", "ai", "Ai", "a" };
  		deleteButSuffixFrom( RV, search, "e", true );
  
  		deleteFrom( R2, new String[] { "ions" } );
  	}
  
  	/**
  	 * Third step of the Porter Algorithm<br>
  	 * refer to http://snowball.sourceforge.net/french/stemmer.html for an explanation
  	 */
  	private void step3() {
  		if (sb.length()>0)
  		{
  			char ch = sb.charAt( sb.length()-1 );
  			if (ch == 'Y')
  			{
  				sb.setCharAt( sb.length()-1, 'i' );
  				setStrings();
  			}
  			else if (ch == 'ç')
  			{
  				sb.setCharAt( sb.length()-1, 'c' );
  				setStrings();
  			}
  		}
  	}
  
  	/**
  	 * Fourth step of the Porter Algorithm<br>
  	 * refer to http://snowball.sourceforge.net/french/stemmer.html for an explanation
  	 */
  	private void step4() {
  		if (sb.length() > 1)
  		{
  			char ch = sb.charAt( sb.length()-1 );
  			if (ch == 's')
  			{
  				char b = sb.charAt( sb.length()-2 );
  				if (b != 'a' && b != 'i' && b != 'o' && b != 'u' && b != 'è' && b != 's')
  				{
  					sb.delete( sb.length() - 1, sb.length());
  					setStrings();
  				}
  			}
  		}
  		boolean found = deleteFromIfPrecededIn( R2, new String[] { "ion" }, RV, "s" );
  		if (!found)
  		found = deleteFromIfPrecededIn( R2, new String[] { "ion" }, RV, "t" );
  
  		replaceFrom( RV, new String[] { "Ière", "ière", "Ier", "ier" }, "i" );
  		deleteFrom( RV, new String[] { "e" } );
  		deleteFromIfPrecededIn( RV, new String[] { "ë" }, R0, "gu" );
  	}
  
  	/**
  	 * Fifth step of the Porter Algorithm<br>
  	 * refer to http://snowball.sourceforge.net/french/stemmer.html for an explanation
  	 */
  	private void step5() {
  		if (R0 != null)
  		{
  			if (R0.endsWith("enn") || R0.endsWith("onn") || R0.endsWith("ett") || R0.endsWith("ell") || R0.endsWith("eill"))
  			{
  				sb.delete( sb.length() - 1, sb.length() );
  				setStrings();
  			}
  		}
  	}
  
  	/**
  	 * Sixth (and last!) step of the Porter Algorithm<br>
  	 * refer to http://snowball.sourceforge.net/french/stemmer.html for an explanation
  	 */
  	private void step6() {
  		if (R0!=null && R0.length()>0)
  		{
  			boolean seenVowel = false;
  			boolean seenConson = false;
  			int pos = -1;
  			for (int i = R0.length()-1; i > -1; i--)
  			{
  				char ch = R0.charAt(i);
  				if (isVowel(ch))
  				{
  					if (!seenVowel)
  					{
  						if (ch == 'é' || ch == 'è')
  						{
  							pos = i;
  							break;
  						}
  					}
  					seenVowel = true;
  				}
  				else
  				{
  					if (seenVowel)
  						break;
  					else
  						seenConson = true;
  				}
  			}
  			if (pos > -1 && seenConson && !seenVowel)
  				sb.setCharAt(pos, 'e');
  		}
  	}
  
  	/**
  	 * Delete a suffix searched in zone "source" if zone "from" contains prefix + search string
  	 *
  	 * @param source java.lang.String - the primary source zone for search
  	 * @param search java.lang.String[] - the strings to search for suppression
  	 * @param from java.lang.String - the secondary source zone for search
  	 * @param prefix java.lang.String - the prefix to add to the search string to test
  	 * @return boolean - true if modified
  	 */
  	private boolean deleteFromIfPrecededIn( String source, String[] search, String from, String prefix ) {
  		boolean found = false;
  		if (source!=null )
  		{
  			for (int i = 0; i < search.length; i++) {
  				if ( source.endsWith( search[i] ))
  				{
  					if (from!=null && from.endsWith( prefix + search[i] ))
  					{
  						sb.delete( sb.length() - search[i].length(), sb.length());
  						found = true;
  						setStrings();
  						break;
  					}
  				}
  			}
  		}
  		return found;
  	}
  
  	/**
  	 * Delete a suffix searched in zone "source" if the preceding letter is (or isn't) a vowel
  	 *
  	 * @param source java.lang.String - the primary source zone for search
  	 * @param search java.lang.String[] - the strings to search for suppression
  	 * @param vowel boolean - true if we need a vowel before the search string
  	 * @param from java.lang.String - the secondary source zone for search (where vowel could be)
  	 * @return boolean - true if modified
  	 */
  	private boolean deleteFromIfTestVowelBeforeIn( String source, String[] search, boolean vowel, String from ) {
  		boolean found = false;
  		if (source!=null && from!=null)
  		{
  			for (int i = 0; i < search.length; i++) {
  				if ( source.endsWith( search[i] ))
  				{
  					if ((search[i].length() + 1) <= from.length())
  					{
  						boolean test = isVowel(sb.charAt(sb.length()-(search[i].length()+1)));
  						if (test == vowel)
  						{
  							sb.delete( sb.length() - search[i].length(), sb.length());
  							modified = true;
  							found = true;
  							setStrings();
  							break;
  						}
  					}
  				}
  			}
  		}
  		return found;
  	}
  
  	/**
  	 * Delete a suffix searched in zone "source" if preceded by the prefix
  	 *
  	 * @param source java.lang.String - the primary source zone for search
  	 * @param search java.lang.String[] - the strings to search for suppression
  	 * @param prefix java.lang.String - the prefix to add to the search string to test
  	 * @param without boolean - true if it will be deleted even without prefix found
  	 */
  	private void deleteButSuffixFrom( String source, String[] search, String prefix, boolean without ) {
  		if (source!=null)
  		{
  			for (int i = 0; i < search.length; i++) {
  				if ( source.endsWith( prefix + search[i] ))
  				{
  					sb.delete( sb.length() - (prefix.length() + search[i].length()), sb.length() );
  					modified = true;
  					setStrings();
  					break;
  				}
  				else if ( without && source.endsWith( search[i] ))
  				{
  					sb.delete( sb.length() - search[i].length(), sb.length() );
  					modified = true;
  					setStrings();
  					break;
  				}
  			}
  		}
  	}
  
  	/**
  	 * Delete a suffix searched in zone "source" if preceded by prefix<br>
  	 * or replace it with the replace string if preceded by the prefix in the zone "from"<br>
  	 * or delete the suffix if specified
  	 *
  	 * @param source java.lang.String - the primary source zone for search
  	 * @param search java.lang.String[] - the strings to search for suppression
  	 * @param prefix java.lang.String - the prefix to add to the search string to test
  	 * @param without boolean - true if it will be deleted even without prefix found
  	 */
  	private void deleteButSuffixFromElseReplace( String source, String[] search, String prefix, boolean without, String from, String replace ) {
  		if (source!=null)
  		{
  			for (int i = 0; i < search.length; i++) {
  				if ( source.endsWith( prefix + search[i] ))
  				{
  					sb.delete( sb.length() - (prefix.length() + search[i].length()), sb.length() );
  					modified = true;
  					setStrings();
  					break;
  				}
  				else if ( from!=null && from.endsWith( prefix + search[i] ))
  				{
  					sb.replace( sb.length() - (prefix.length() + search[i].length()), sb.length(), replace );
  					modified = true;
  					setStrings();
  					break;
  				}
  				else if ( without && source.endsWith( search[i] ))
  				{
  					sb.delete( sb.length() - search[i].length(), sb.length() );
  					modified = true;
  					setStrings();
  					break;
  				}
  			}
  		}
  	}
  
  	/**
  	 * Replace a search string with another within the source zone
  	 *
  	 * @param source java.lang.String - the source zone for search
  	 * @param search java.lang.String[] - the strings to search for replacement
  	 * @param replace java.lang.String - the replacement string
  	 */
  	private boolean replaceFrom( String source, String[] search, String replace ) {
  		boolean found = false;
  		if (source!=null)
  		{
  			for (int i = 0; i < search.length; i++) {
  				if ( source.endsWith( search[i] ))
  				{
  					sb.replace( sb.length() - search[i].length(), sb.length(), replace );
  					modified = true;
  					found = true;
  					setStrings();
  					break;
  				}
  			}
  		}
  		return found;
  	}
  
  	/**
  	 * Delete a search string within the source zone
  	 *
  	 * @param source the source zone for search
  	 * @param suffix the strings to search for suppression
  	 */
  	private void deleteFrom(String source, String[] suffix ) {
  		if (source!=null)
  		{
  			for (int i = 0; i < suffix.length; i++) {
  				if (source.endsWith( suffix[i] ))
  				{
  					sb.delete( sb.length() - suffix[i].length(), sb.length());
  					modified = true;
  					setStrings();
  					break;
  				}
  			}
  		}
  	}
  
  	/**
  	 * Test if a char is a french vowel, including accentuated ones
  	 *
  	 * @param ch the char to test
  	 * @return boolean - true if the char is a vowel
  	 */
  	private boolean isVowel(char ch) {
  		switch (ch)
  		{
  			case 'a':
  			case 'e':
  			case 'i':
  			case 'o':
  			case 'u':
  			case 'y':
  			case 'â':
  			case 'à':
  			case 'ë':
  			case 'é':
  			case 'ê':
  			case 'è':
  			case 'ï':
  			case 'î':
  			case 'ô':
  			case 'ü':
  			case 'ù':
  			case 'û':
  				return true;
  			default:
  				return false;
  		}
  	}
  
  	/**
  	 * Retrieve the "R zone" (1 or 2 depending on the buffer) and return the corresponding string<br>
  	 * "R is the region after the first non-vowel following a vowel
  	 * or is the null region at the end of the word if there is no such non-vowel"<br>
  	 * @param buffer java.lang.StringBuilder - the in buffer
  	 * @return java.lang.String - the resulting string
  	 */
  	private String retrieveR( StringBuilder buffer ) {
  		int len = buffer.length();
  		int pos = -1;
  		for (int c = 0; c < len; c++) {
  			if (isVowel( buffer.charAt( c )))
  			{
  				pos = c;
  				break;
  			}
  		}
  		if (pos > -1)
  		{
  			int consonne = -1;
  			for (int c = pos; c < len; c++) {
  				if (!isVowel(buffer.charAt( c )))
  				{
  					consonne = c;
  					break;
  				}
  			}
  			if (consonne > -1 && (consonne+1) < len)
  				return buffer.substring( consonne+1, len );
  			else
  				return null;
  		}
  		else
  			return null;
  	}
  
  	/**
  	 * Retrieve the "RV zone" from a buffer an return the corresponding string<br>
  	 * "If the word begins with two vowels, RV is the region after the third letter,
  	 * otherwise the region after the first vowel not at the beginning of the word,
  	 * or the end of the word if these positions cannot be found."<br>
  	 * @param buffer java.lang.StringBuilder - the in buffer
  	 * @return java.lang.String - the resulting string
  	 */
  	private String retrieveRV( StringBuilder buffer ) {
  		int len = buffer.length();
  		if ( buffer.length() > 3)
  		{
  			if ( isVowel(buffer.charAt( 0 )) && isVowel(buffer.charAt( 1 ))) {
  				return buffer.substring(3,len);
  			}
  			else
  			{
  				int pos = 0;
  				for (int c = 1; c < len; c++) {
  					if (isVowel( buffer.charAt( c )))
  					{
  						pos = c;
  						break;
  					}
  				}
  				if ( pos+1 < len )
  					return buffer.substring( pos+1, len );
  				else
  					return null;
  			}
  		}
  		else
  			return null;
  	}
  
  
  
      /**
  	 * Turns u and i preceded AND followed by a vowel to UpperCase<br>
  	 * Turns y preceded OR followed by a vowel to UpperCase<br>
  	 * Turns u preceded by q to UpperCase<br>
       *
       * @param buffer java.util.StringBuilder - the buffer to treat
       * @return java.util.StringBuilder - the treated buffer
       */
      private StringBuilder treatVowels( StringBuilder buffer ) {
  		for ( int c = 0; c < buffer.length(); c++ ) {
  			char ch = buffer.charAt( c );
  
  			if (c == 0) // first char
  			{
  				if (buffer.length()>1)
  				{
  					if (ch == 'y' && isVowel(buffer.charAt( c + 1 )))
  						buffer.setCharAt( c, 'Y' );
  				}
  			}
  			else if (c == buffer.length()-1) // last char
  			{
  				if (ch == 'u' && buffer.charAt( c - 1 ) == 'q')
  					buffer.setCharAt( c, 'U' );
  				if (ch == 'y' && isVowel(buffer.charAt( c - 1 )))
  					buffer.setCharAt( c, 'Y' );
  			}
  			else // other cases
  			{
  				if (ch == 'u')
  				{
  					if (buffer.charAt( c - 1) == 'q')
  						buffer.setCharAt( c, 'U' );
  					else if (isVowel(buffer.charAt( c - 1 )) && isVowel(buffer.charAt( c + 1 )))
  						buffer.setCharAt( c, 'U' );
  				}
  				if (ch == 'i')
  				{
  					if (isVowel(buffer.charAt( c - 1 )) && isVowel(buffer.charAt( c + 1 )))
  						buffer.setCharAt( c, 'I' );
  				}
  				if (ch == 'y')
  				{
  					if (isVowel(buffer.charAt( c - 1 )) || isVowel(buffer.charAt( c + 1 )))
  						buffer.setCharAt( c, 'Y' );
  				}
  			}
  		}
  
  		return buffer;
      }
  
      /**
       * Checks a term if it can be processed correctly.
       *
       * @return boolean - true if, and only if, the given term consists in letters.
       */
      private boolean isStemmable( String term ) {
  		boolean upper = false;
  		int first = -1;
  		for ( int c = 0; c < term.length(); c++ ) {
  			// Discard terms that contain non-letter characters.
  			if ( !Character.isLetter( term.charAt( c ) ) ) {
  				return false;
  			}
  			// Discard terms that contain multiple uppercase letters.
  			if ( Character.isUpperCase( term.charAt( c ) ) ) {
  				if ( upper ) {
  					return false;
  				}
  			// First encountered uppercase letter, set flag and save
  			// position.
  				else {
  					first = c;
  					upper = true;
  				}
  			}
  		}
  		// Discard the term if it contains a single uppercase letter that
  		// is not starting the term.
  		if ( first > 0 ) {
  			return false;
  		}
  		return true;
      }
  }
  