+++ /dev/null
-/*******************************************************************************
- * Copyright (c) 2000, 2003 IBM Corporation and others.
- * All rights reserved. This program and the accompanying materials
- * are made available under the terms of the Common Public License v1.0
- * which accompanies this distribution, and is available at
- * http://www.eclipse.org/legal/cpl-v10.html
- *
- * Contributors:
- * IBM Corporation - initial API and implementation
- *******************************************************************************/
-
-package net.sourceforge.phpdt.internal.ui.text.spelling.engine;
-
-/**
- * Default phonetic distance algorithm for english words.
- * <p>
- * This algorithm implements the Levenshtein text edit distance.
- * </p>
- *
- * @since 3.0
- */
-public final class DefaultPhoneticDistanceAlgorithm implements IPhoneticDistanceAlgorithm {
-
- /** The change case cost */
- public static final int COST_CASE= 10;
-
- /** The insert character cost */
- public static final int COST_INSERT= 95;
-
- /** The remove character cost */
- public static final int COST_REMOVE= 95;
-
- /** The substitute characters cost */
- public static final int COST_SUBSTITUTE= 100;
-
- /** The swap characters cost */
- public static final int COST_SWAP= 90;
-
- /*
- * @see org.eclipse.spelling.done.IPhoneticDistanceAlgorithm#getDistance(java.lang.String,java.lang.String)
- */
- public final int getDistance(final String from, final String to) {
-
- final char[] first= (" " + from).toCharArray(); //$NON-NLS-1$
- final char[] second= (" " + to).toCharArray(); //$NON-NLS-1$
-
- final int rows= first.length;
- final int columns= second.length;
-
- final int[][] metric= new int[rows][columns];
- for (int column= 1; column < columns; column++)
- metric[0][column]= metric[0][column - 1] + COST_REMOVE;
-
- for (int row= 1; row < rows; row++)
- metric[row][0]= metric[row - 1][0] + COST_INSERT;
-
- char source, target;
-
- int swap= Integer.MAX_VALUE;
- int change= Integer.MAX_VALUE;
-
- int minimum, diagonal, insert, remove;
- for (int row= 1; row < rows; row++) {
-
- source= first[row];
- for (int column= 1; column < columns; column++) {
-
- target= second[column];
- diagonal= metric[row - 1][column - 1];
-
- if (source == target) {
- metric[row][column]= diagonal;
- continue;
- }
-
- change= Integer.MAX_VALUE;
- if (Character.toLowerCase(source) == Character.toLowerCase(target))
- change= COST_CASE + diagonal;
-
- swap= Integer.MAX_VALUE;
- if (row != 1 && column != 1 && source == second[column - 1] && first[row - 1] == target)
- swap= COST_SWAP + metric[row - 2][column - 2];
-
- minimum= COST_SUBSTITUTE + diagonal;
- if (swap < minimum)
- minimum= swap;
-
- remove= metric[row][column - 1];
- if (COST_REMOVE + remove < minimum)
- minimum= COST_REMOVE + remove;
-
- insert= metric[row - 1][column];
- if (COST_INSERT + insert < minimum)
- minimum= COST_INSERT + insert;
- if (change < minimum)
- minimum= change;
-
- metric[row][column]= minimum;
- }
- }
- return metric[rows - 1][columns - 1];
- }
-}