1 /* TranslateFunction.java -- 2 Copyright (C) 2004 Free Software Foundation, Inc. 3 4 This file is part of GNU Classpath. 5 6 GNU Classpath is free software; you can redistribute it and/or modify 7 it under the terms of the GNU General Public License as published by 8 the Free Software Foundation; either version 2, or (at your option) 9 any later version. 10 11 GNU Classpath is distributed in the hope that it will be useful, but 12 WITHOUT ANY WARRANTY; without even the implied warranty of 13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 14 General Public License for more details. 15 16 You should have received a copy of the GNU General Public License 17 along with GNU Classpath; see the file COPYING. If not, write to the 18 Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 19 02110-1301 USA. 20 21 Linking this library statically or dynamically with other modules is 22 making a combined work based on this library. Thus, the terms and 23 conditions of the GNU General Public License cover the whole 24 combination. 25 26 As a special exception, the copyright holders of this library give you 27 permission to link this library with independent modules to produce an 28 executable, regardless of the license terms of these independent 29 modules, and to copy and distribute the resulting executable under 30 terms of your choice, provided that you also meet, for each linked 31 independent module, the terms and conditions of the license of that 32 module. An independent module is a module which is not derived from 33 or based on this library. If you modify this library, you may extend 34 this exception to your version of the library, but you are not 35 obligated to do so. If you do not wish to do so, delete this 36 exception statement from your version. */ 37 38 package gnu.xml.xpath; 39 40 import gnu.java.lang.CPStringBuilder; 41 42 import java.util.List; 43 import javax.xml.namespace.QName; 44 import org.w3c.dom.Node; 45 46 /** 47 * The <code>translate</code> function returns the first argument string 48 * with occurrences of characters in the second argument string replaced by 49 * the character at the corresponding position in the third argument string. 50 * For example, translate("bar","abc","ABC") returns the string BAr. If 51 * there is a character in the second argument string with no character at a 52 * corresponding position in the third argument string (because the second 53 * argument string is longer than the third argument string), then 54 * occurrences of that character in the first argument string are removed. 55 * For example, translate("--aaa--","abc-","ABC") returns "AAA". If a 56 * character occurs more than once in the second argument string, then the 57 * first occurrence determines the replacement character. If the third 58 * argument string is longer than the second argument string, then excess 59 * characters are ignored. 60 * 61 * @author <a href='mailto:dog@gnu.org'>Chris Burdess</a> 62 */ 63 final class TranslateFunction 64 extends Expr 65 { 66 67 final Expr arg1; 68 final Expr arg2; 69 final Expr arg3; 70 TranslateFunction(List<Expr> args)71 TranslateFunction(List<Expr> args) 72 { 73 this(args.get(0), args.get(1), args.get(2)); 74 } 75 TranslateFunction(Expr arg1, Expr arg2, Expr arg3)76 TranslateFunction(Expr arg1, Expr arg2, Expr arg3) 77 { 78 this.arg1 = arg1; 79 this.arg2 = arg2; 80 this.arg3 = arg3; 81 } 82 evaluate(Node context, int pos, int len)83 public Object evaluate(Node context, int pos, int len) 84 { 85 Object val1 = arg1.evaluate(context, pos, len); 86 Object val2 = arg2.evaluate(context, pos, len); 87 Object val3 = arg3.evaluate(context, pos, len); 88 String string = _string(context, val1); 89 String search = _string(context, val2); 90 String replace = _string(context, val3); 91 CPStringBuilder buf = new CPStringBuilder(); 92 int l1 = string.length(); 93 int l2 = search.length(); 94 int l3 = replace.length(); 95 for (int i = 0; i < l1; i++) 96 { 97 char c = string.charAt(i); 98 boolean replaced = false; 99 for (int j = 0; j < l2; j++) 100 { 101 if (c == search.charAt(j)) 102 { 103 if (j < l3) 104 { 105 buf.append(replace.charAt(j)); 106 } 107 replaced = true; 108 } 109 } 110 if (!replaced) 111 { 112 buf.append(c); 113 } 114 } 115 return buf.toString(); 116 } 117 clone(Object context)118 public Expr clone(Object context) 119 { 120 return new TranslateFunction(arg1.clone(context), arg2.clone(context), 121 arg3.clone(context)); 122 } 123 references(QName var)124 public boolean references(QName var) 125 { 126 return (arg1.references(var) || arg2.references(var) || 127 arg3.references(var)); 128 } 129 toString()130 public String toString() 131 { 132 return "translate(" + arg1 + "," + arg2 + "," + arg3 + ")"; 133 } 134 135 } 136