org.apache.activemq.filter.function.splitFunction 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.activemq.filter.function;
import org.apache.activemq.filter.FunctionCallExpression;
import org.apache.activemq.filter.MessageEvaluationContext;
/**
* Function which splits a string into a list of strings given a regular expression for the separator.
*/
public class splitFunction 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 two or three arguments are passed to the function; false - otherwise.
*/
public boolean isValid(FunctionCallExpression expr) {
if ((expr.getNumArguments() >= 2) && (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 - indicating this filter function never evaluates to a boolean result.
*/
public boolean returnsBoolean(FunctionCallExpression expr) {
return false;
}
/**
* Evaluate the given expression for this function in the given context. A list of zero or more strings
* results from the evaluation. The result of the evaluation of the first argument is split with the regular
* expression which results from the evaluation of the second argument. If a third argument is given, it
* is an integer which limits the split. String#split() performs the split.
*
* The first two arguments must be Strings. If a third is given, it must be an Integer.
*
* @param expr - the expression consisting of a call to this function.
* @return List - a list of Strings resulting from the split.
*/
public Object evaluate(FunctionCallExpression expr, MessageEvaluationContext message_ctx)
throws javax.jms.JMSException {
String src;
String split_pat;
String[] result;
src = (String) expr.getArgument(0).evaluate(message_ctx);
split_pat = (String) expr.getArgument(1).evaluate(message_ctx);
if (expr.getNumArguments() > 2) {
Integer limit;
limit = (Integer) expr.getArgument(2).evaluate(message_ctx);
result = src.split(split_pat, limit.intValue());
} else {
result = src.split(split_pat);
}
return java.util.Arrays.asList(result);
}
}