/*
* Copyright 2014 the original author or authors.
*
* 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 org.springframework.data.hadoop.store.expression;
import org.springframework.expression.AccessException;
import org.springframework.expression.EvaluationContext;
import org.springframework.expression.MethodExecutor;
import org.springframework.expression.TypedValue;
/**
* A {@link MethodExecutor} making it easier to combine
* paths instead of concatenating in spel itself.
*
* @author Janne Valkealahti
*
*/
public class PathCombiningMethodExecutor implements MethodExecutor {
private final static String DEFAULT_PATH_DELIMITER = "/";
private final String delimiter;
/**
* Instantiates a new path combine method executor with
* default delimiter '/'.
*/
public PathCombiningMethodExecutor() {
this(DEFAULT_PATH_DELIMITER);
}
/**
* Instantiates a new path combine method executor.
*
* @param delimiter the delimiter for paths
*/
public PathCombiningMethodExecutor(String delimiter) {
this.delimiter = delimiter;
}
@Override
public TypedValue execute(EvaluationContext context, Object target, Object... arguments) throws AccessException {
StringBuilder buf = new StringBuilder();
for (int i = 0; i < arguments.length; i++) {
buf.append(arguments[i]);
if (i+1 < arguments.length) {
buf.append(delimiter);
}
}
return new TypedValue(buf.toString());
}
}