content: /*
   *  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
   *
   *      https://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 java.util.regex.Matcher;
  import java.util.regex.Pattern;
  import java.util.regex.PatternSyntaxException;
  
  import org.apache.tools.ant.BuildException;
  
  /**
   * Implementation of RegexpMatcher for the built-in regexp matcher of
   * JDK 1.4. UNIX_LINES option is enabled as a default.
   *
   */
  public class Jdk14RegexpMatcher implements RegexpMatcher {
  
      private String pattern;
  
      /**
       * Set the regexp pattern from the String description.
       * @param pattern the pattern to match
       */
      @Override
      public void setPattern(String pattern) {
          this.pattern = pattern;
      }
  
      /**
       * Get a String representation of the regexp pattern
       * @return the pattern
       * @throws BuildException on error
       */
      @Override
      public String getPattern() {
          return pattern;
      }
  
      /**
       * Get a compiled representation of the regexp pattern
       * @param options the options
       * @return the compiled pattern
       * @throws BuildException on error
       */
      protected Pattern getCompiledPattern(int options)
          throws BuildException {
          try {
              return Pattern.compile(this.pattern, getCompilerOptions(options));
          } catch (PatternSyntaxException e) {
              throw new BuildException(e);
          }
      }
  
      /**
       * Does the given argument match the pattern using default options?
       * @param argument the string to match against
       * @return true if the pattern matches
       * @throws BuildException on error
       */
      @Override
      public boolean matches(String argument) throws BuildException {
          return matches(argument, MATCH_DEFAULT);
      }
  
      /**
       * Does the given argument match the pattern?
       * @param input the string to match against
       * @param options the regex options to use
       * @return true if the pattern matches
       * @throws BuildException on error
       */
      @Override
      public boolean matches(String input, int options)
          throws BuildException {
          try {
              return getCompiledPattern(options).matcher(input).find();
          } catch (Exception e) {
              throw new BuildException(e);
          }
      }
  
      /**
       * Returns a Vector of matched groups found in the argument
       * using default options.
       *
       * <p>Group 0 will be the full match, the rest are the
       * parenthesized subexpressions</p>.
       *
       * @param argument the string to match against
       * @return the vector of groups
       * @throws BuildException on error
       */
      @Override
      public Vector<String> getGroups(String argument) throws BuildException {
          return getGroups(argument, MATCH_DEFAULT);
      }
  
      /**
       * Returns a Vector of matched groups found in the argument.
       *
       * <p>Group 0 will be the full match, the rest are the
       * parenthesized subexpressions</p>.
       *
       * @param input the string to match against
       * @param options the regex options to use
       * @return the vector of groups
       * @throws BuildException on error
       */
      @Override
      public Vector<String> getGroups(String input, int options)
          throws BuildException {
          Pattern p = getCompiledPattern(options);
          Matcher matcher = p.matcher(input);
          if (!matcher.find()) {
              return null;
          }
          Vector<String> v = new Vector<>();
          int cnt = matcher.groupCount();
          for (int i = 0; i <= cnt; i++) {
              String match = matcher.group(i);
              // treat non-matching groups as empty matches
              if (match == null) {
                  match = "";
              }
              v.add(match);
          }
          return v;
      }
  
      /**
       * Convert the generic options to the regex compiler specific options.
       * @param options the generic options
       * @return the specific options
       */
      protected int getCompilerOptions(int options) {
          // be strict about line separator
          int cOptions = Pattern.UNIX_LINES;
  
          if (RegexpUtil.hasFlag(options, MATCH_CASE_INSENSITIVE)) {
              cOptions |= Pattern.CASE_INSENSITIVE;
          }
          if (RegexpUtil.hasFlag(options, MATCH_MULTILINE)) {
              cOptions |= Pattern.MULTILINE;
          }
          if (RegexpUtil.hasFlag(options, MATCH_SINGLELINE)) {
              cOptions |= Pattern.DOTALL;
          }
  
          return cOptions;
      }
  
  }
  