org.janusgraph.graphdb.database.serialize.AttributeUtils Maven / Gradle / Ivy
// Copyright 2017 JanusGraph 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.janusgraph.graphdb.database.serialize;
import org.janusgraph.core.attribute.Geoshape;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
* @author Matthias Broecheler ([email protected])
*/
public class AttributeUtils {
private static final Logger log = LoggerFactory.getLogger(AttributeUtils.class);
public static boolean isWholeNumber(Number n) {
return isWholeNumber(n.getClass());
}
public static boolean isWholeNumber(Class clazz) {
return clazz.equals(Long.class) || clazz.equals(Integer.class) ||
clazz.equals(Short.class) || clazz.equals(Byte.class);
}
public static boolean isDecimal(Class clazz) {
return clazz.equals(Double.class) || clazz.equals(Float.class);
}
public static boolean isString(Object o) {
return isString(o.getClass());
}
public static boolean isString(Class clazz) {
return clazz.equals(String.class);
}
public static boolean isGeo(Class clazz) {
return clazz.equals(Geoshape.class);
}
/**
* Compares the two elements like {@link java.util.Comparator#compare(Object, Object)} but returns
* null in case the two elements are not comparable.
*
* @param a
* @param b
* @return
*/
public static Integer compare(Object a, Object b) {
if (a==b) return 0;
if (a==null || b==null) return null;
assert a!=null && b!=null;
if (a instanceof Number && b instanceof Number) {
Number an = (Number)a;
Number bn = (Number)b;
if (Double.isNaN(an.doubleValue()) || Double.isNaN(bn.doubleValue())) {
if (Double.isNaN(an.doubleValue()) && Double.isNaN(bn.doubleValue())) return 0;
else return null;
} else {
if (an.doubleValue()==bn.doubleValue()) {
// Long.compare(long,long) is only available since Java 1.7
//return Long.compare(an.longValue(),bn.longValue());
return Long.compare(an.longValue(), bn.longValue());
} else {
return Double.compare(an.doubleValue(),bn.doubleValue());
}
}
} else {
try {
return ((Comparable)a).compareTo(b);
} catch (Throwable e) {
log.debug("Could not compare elements: {} - {}",a,b);
return null;
}
}
}
}