com.google.common.base.FunctionalEquivalence 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) 2011 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.base;
import static com.google.common.base.Preconditions.checkNotNull;
import com.google.common.annotations.GwtCompatible;
import java.io.Serializable;
import javax.annotation.CheckForNull;
import org.checkerframework.checker.nullness.qual.Nullable;
/**
* Equivalence applied on functional result.
*
* @author Bob Lee
* @since 10.0
*/
@GwtCompatible
@ElementTypesAreNonnullByDefault
final class FunctionalEquivalence extends Equivalence implements Serializable {
private static final long serialVersionUID = 0;
private final Function super F, ? extends @Nullable T> function;
private final Equivalence resultEquivalence;
FunctionalEquivalence(
Function super F, ? extends @Nullable T> function, Equivalence resultEquivalence) {
this.function = checkNotNull(function);
this.resultEquivalence = checkNotNull(resultEquivalence);
}
@Override
protected boolean doEquivalent(F a, F b) {
return resultEquivalence.equivalent(function.apply(a), function.apply(b));
}
@Override
protected int doHash(F a) {
return resultEquivalence.hash(function.apply(a));
}
@Override
public boolean equals(@CheckForNull Object obj) {
if (obj == this) {
return true;
}
if (obj instanceof FunctionalEquivalence) {
FunctionalEquivalence, ?> that = (FunctionalEquivalence, ?>) obj;
return function.equals(that.function) && resultEquivalence.equals(that.resultEquivalence);
}
return false;
}
@Override
public int hashCode() {
return Objects.hashCode(function, resultEquivalence);
}
@Override
public String toString() {
return resultEquivalence + ".onResultOf(" + function + ")";
}
}