com.google.common.collect.NullsLastOrdering Maven / Gradle / Ivy
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This artifact provides a single jar that contains all classes required to use remote EJB and JMS, including
all dependencies. It is intended for use by those not using maven, maven users should just import the EJB and
JMS BOM's instead (shaded JAR's cause lots of problems with maven, as it is very easy to inadvertently end up
with different versions on classes on the class path).
/*
* Copyright (C) 2007 The Guava 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 com.google.common.collect;
import com.google.common.annotations.GwtCompatible;
import java.io.Serializable;
import javax.annotation.CheckForNull;
import org.checkerframework.checker.nullness.qual.NonNull;
import org.checkerframework.checker.nullness.qual.Nullable;
/** An ordering that treats {@code null} as greater than all other values. */
@GwtCompatible(serializable = true)
@ElementTypesAreNonnullByDefault
final class NullsLastOrdering extends Ordering<@Nullable T>
implements Serializable {
final Ordering ordering;
NullsLastOrdering(Ordering ordering) {
this.ordering = ordering;
}
@Override
public int compare(@CheckForNull T left, @CheckForNull T right) {
if (left == right) {
return 0;
}
if (left == null) {
return LEFT_IS_GREATER;
}
if (right == null) {
return RIGHT_IS_GREATER;
}
return ordering.compare(left, right);
}
@Override
@SuppressWarnings("nullness") // should be safe, but not sure if we can avoid the warning
public Ordering reverse() {
// ordering.reverse() might be optimized, so let it do its thing
return ordering.reverse().<@NonNull S>nullsFirst();
}
@Override
public Ordering<@Nullable S> nullsFirst() {
return ordering.<@NonNull S>nullsFirst();
}
@SuppressWarnings("unchecked") // still need the right way to explain this
@Override
public Ordering<@Nullable S> nullsLast() {
return (Ordering<@Nullable S>) this;
}
@Override
public boolean equals(@CheckForNull Object object) {
if (object == this) {
return true;
}
if (object instanceof NullsLastOrdering) {
NullsLastOrdering that = (NullsLastOrdering) object;
return this.ordering.equals(that.ordering);
}
return false;
}
@Override
public int hashCode() {
return ordering.hashCode() ^ -921210296; // meaningless
}
@Override
public String toString() {
return ordering + ".nullsLast()";
}
private static final long serialVersionUID = 0;
}