org.codehaus.jackson.map.util.Comparators Maven / Gradle / Ivy
package org.codehaus.jackson.map.util;
import java.lang.reflect.Array;
/**
* Helper class for constructing objects for comparing content values
*
* @since 1.9.0
*/
public class Comparators
{
/**
* Helper method used for constructing simple value comparator used for
* comparing arrays for content equality.
*
* Note: current implementation is not optimized for speed; if performance
* ever becomes an issue, it is possible to construct much more efficient
* typed instances (one for Object[] and sub-types; one per primitive type)
*
* @since 1.9
*/
public static Object getArrayComparator(final Object defaultValue)
{
final int length = Array.getLength(defaultValue);
return new Object() {
@Override
public boolean equals(Object other) {
if (other == this) return true;
if (other == null || other.getClass() != defaultValue.getClass()) {
return false;
}
if (Array.getLength(other) != length) return false;
// so far so good: compare actual equality; but only shallow one
for (int i = 0; i < length; ++i) {
Object value1 = Array.get(defaultValue, i);
Object value2 = Array.get(other, i);
if (value1 == value2) continue;
if (value1 != null) {
if (!value1.equals(value2)) {
return false;
}
}
}
return true;
}
};
}
}