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
   *
   *      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.activemq.filter.function;
  
  import org.apache.activemq.filter.FunctionCallExpression;
  import org.apache.activemq.filter.MessageEvaluationContext;
  
  /**
   * Function which replaces regular expression matches in a source string to a replacement literal.
   * <p/>
   * For Example:
   * REPLACE('1,2/3', '[,/]', ';') returns '1;2;3'
   */
  
  public class replaceFunction implements FilterFunction {
      /**
       * Check whether the given expression is valid for this function.
       *
       * @param    expr - the expression consisting of a call to this function.
       * @return true - if three arguments are passed to the function; false - otherwise.
       */
  
      public boolean isValid(FunctionCallExpression expr) {
          if (expr.getNumArguments() == 3)
              return true;
  
          return false;
      }
  
  
      /**
       * Indicate that this function does not return a boolean value.
       *
       * @param    expr - the expression consisting of a call to this function.
       * @return false - this filter function always evaluates to a string.
       */
  
      public boolean returnsBoolean(FunctionCallExpression expr) {
          return false;
      }
  
  
      /**
       * Evaluate the given expression for this function in the given context.  The result of the evaluation is a
       * string with all matches of the regular expression, from the evaluation of the second argument, replaced by
       * the string result from the evaluation of the third argument.  Replacement is performed by
       * String#replaceAll().
       * <p/>
       * Note that all three arguments must be Strings.
       *
       * @param    expr - the expression consisting of a call to this function.
       * @return String - the result of the replacement.
       */
  
      public Object evaluate(FunctionCallExpression expr, MessageEvaluationContext message_ctx)
              throws jakarta.jms.JMSException {
          String src;
          String match_regex;
          String repl_lit;
          String result;
  
          src = (String) expr.getArgument(0).evaluate(message_ctx);
          match_regex = (String) expr.getArgument(1).evaluate(message_ctx);
          repl_lit = (String) expr.getArgument(2).evaluate(message_ctx);
  
          result = src.replaceAll(match_regex, repl_lit);
  
          return result;
      }
  }
  