com.netflix.config.DefaultContextualPredicate Maven / Gradle / Ivy
/**
* Copyright 2014 Netflix, Inc.
*
* 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.netflix.config;
import java.util.Collection;
import java.util.Map;
import javax.annotation.Nullable;
import com.google.common.base.Function;
import com.google.common.base.Predicate;
/**
* The default predicate (used by {@link DynamicContextualProperty}) which takes a Function to get the value of
* key included in the JSON blob as the input string value of {@link DynamicContextualProperty}.
*
* @author awang
*
*/
public class DefaultContextualPredicate implements Predicate>> {
private final Function getValueFromKeyFunction;
public static final DefaultContextualPredicate PROPERTY_BASED = new DefaultContextualPredicate(new Function() {
@Override
public String apply(@Nullable String input) {
return DynamicProperty.getInstance(input).getString();
}
});
public DefaultContextualPredicate(Function getValueFromKeyFunction) {
this.getValueFromKeyFunction = getValueFromKeyFunction;
}
/**
* For each key in the passed in map, this function returns true if
*
* the value derived from the key using the function (passed in from the constructor) matches any of the value included for the same key in the map
* the above holds true for all keys in the map
*
*/
@Override
public boolean apply(@Nullable Map> input) {
if (null == input) {
throw new NullPointerException();
}
for (Map.Entry> entry: input.entrySet()) {
String key = entry.getKey();
Collection value = entry.getValue();
if (!value.contains(getValueFromKeyFunction.apply(key))) {
return false;
}
}
return true;
}
}