org.simmetrics.metrics.Identity Maven / Gradle / Ivy
/*
* #%L
* Simmetrics Core
* %%
* Copyright (C) 2014 - 2015 Simmetrics 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.
* #L%
*/
package org.simmetrics.metrics;
import static com.google.common.base.Preconditions.checkNotNull;
import org.simmetrics.Metric;
/**
* Identity metric that returns 1.0 when the inputs are equals, and 0.0 when
* they're not.
*
*
* similarity(a,b) = equals(a,b) ? 1.0f : 0.0f
*
*
* This class is immutable and thread-safe.
*
* @param
* type of token
*/
public final class Identity implements Metric {
@Override
public float compare(T a, T b) {
checkNotNull(a);
checkNotNull(b);
return a.equals(b) ? 1.0f : 0.0f;
}
@Override
public String toString() {
return "Identity";
}
}