/*
* Copyright 2014, The Sporting Exchange Limited
*
* 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.betfair.cougar.util.configuration;
import java.util.*;
public class Sets {
/**
* Given a map and a set of keys, return a set containing the values referred-to by the keys.
* If the map is null or the keys are null, the EMPTY_SET is returned.
* If a passed key does not exist in the map, nothing is added to the set.
* However, if the key is present and maps to null, null is added to the set.
*/
public static final Set fromMap(Map map, Object... keys) {
if (keys != null && map != null) {
Set answer = new HashSet();
for (Object key : keys) {
if (map.containsKey(key)) {
answer.add(map.get(key));
}
}
return Collections.unmodifiableSet(answer);
}
return Collections.EMPTY_SET;
}
/**
* Given a comma-separated list of values, return a set of those values.
* If the passed string is null, the EMPTY_SET is returned.
* If the passed string is empty, the EMPTY_SET is returned.
*/
public static final Set<String> fromCommaSeparatedValues(String csv) {
if (csv == null || csv.isEmpty()) {
return Collections.EMPTY_SET;
}
String[] tokens = csv.split(",");
return new HashSet<String>(Arrays.asList(tokens));
}
}