org.apache.tools.ant.util.regexp.JakartaRegexpRegexp Maven / Gradle / Ivy
/*
* 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.
*
*/
package org.apache.tools.ant.util.regexp;
import java.util.Vector;
import org.apache.regexp.RE;
import org.apache.tools.ant.BuildException;
/***
* Regular expression implementation using the Jakarta Regexp package
*/
public class JakartaRegexpRegexp extends JakartaRegexpMatcher
implements Regexp {
private static final int DECIMAL = 10;
/** Constructor for JakartaRegexpRegexp */
public JakartaRegexpRegexp() {
super();
}
/**
* Convert ant regexp substitution option to apache regex options.
*
* @param options the ant regexp options
* @return the apache regex substition options
*/
protected int getSubsOptions(int options) {
int subsOptions = RE.REPLACE_FIRSTONLY;
if (RegexpUtil.hasFlag(options, REPLACE_ALL)) {
subsOptions = RE.REPLACE_ALL;
}
return subsOptions;
}
/**
* Perform a substitution on the regular expression.
* @param input The string to substitute on
* @param argument The string which defines the substitution
* @param options The list of options for the match and replace.
* @return the result of the operation
* @throws BuildException on error
*/
public String substitute(String input, String argument, int options)
throws BuildException {
Vector v = getGroups(input, options);
// replace \1 with the corresponding group
StringBuffer result = new StringBuffer();
for (int i = 0; i < argument.length(); i++) {
char c = argument.charAt(i);
if (c == '\\') {
if (++i < argument.length()) {
c = argument.charAt(i);
int value = Character.digit(c, DECIMAL);
if (value > -1) {
result.append((String) v.elementAt(value));
} else {
result.append(c);
}
} else {
// TODO - should throw an exception instead?
result.append('\\');
}
} else {
result.append(c);
}
}
argument = result.toString();
RE reg = getCompiledPattern(options);
int sOptions = getSubsOptions(options);
return reg.subst(input, argument, sOptions);
}
}