content: /*
   * Copyright 1999-2018 Alibaba Group Holding Ltd.
   *
   * Licensed 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 com.alibaba.druid.util;
  
  public class ServletPathMatcher implements PatternMatcher {
      private static final ServletPathMatcher INSTANCE = new ServletPathMatcher();
  
      public static ServletPathMatcher getInstance() {
          return INSTANCE;
      }
  
      private ServletPathMatcher() {
      }
  
      /**
       * <p>
       * three type: endsWithMatch(eg. /xxx*=/xxx/xyz), startsWithMatch(eg.
       * *.xxx=abc.xxx), equals(eg. /xxx=/xxx).
       * </p>
       * <b>Notice</b>: *xxx* will match *xxxyyyy. endsWithMatch first.
       */
      @Override
      public boolean matches(String pattern, String source) {
          if (pattern == null || source == null) {
              return false;
          }
          pattern = pattern.trim();
          source = source.trim();
          if (pattern.endsWith("*")) {
              // pattern: /druid* source:/druid/index.html
              int length = pattern.length() - 1;
              if (source.length() >= length) {
                  if (pattern.substring(0, length).equals(
                          source.substring(0, length))) {
                      return true;
                  }
              }
          } else if (pattern.startsWith("*")) {
              // pattern: *.html source:/xx/xx.html
              int length = pattern.length() - 1;
              if (source.length() >= length
                      && source.endsWith(pattern.substring(1))) {
                  return true;
              }
          } else if (pattern.contains("*")) {
              // pattern:  /druid/*/index.html source:/druid/admin/index.html
              int start = pattern.indexOf("*");
              int end = pattern.lastIndexOf("*");
              if (source.startsWith(pattern.substring(0, start))
                      && source.endsWith(pattern.substring(end + 1))) {
                  return true;
              }
          } else {
              // pattern: /druid/index.html source:/druid/index.html
              if (pattern.equals(source)) {
                  return true;
              }
          }
          return false;
      }
  
  }
  