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A Speedment bundle that shades all dependencies into one jar. This is
useful when deploying an application on a server.
The newest version!
/*
*
* Copyright (c) 2006-2019, Speedment, Inc. All Rights Reserved.
*
* 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.speedment.common.lazy;
import java.util.function.Supplier;
/**
* Generic lazy initialization interface.
*
* @author pemi
* @param the type of the lazy initialized value
*/
@FunctionalInterface
public interface Lazy {
/**
* Returns the value of the Lazy instance. If the Lazy instance is not
* initialized, the supplier will be called before the value is returned.
* The method guarantees that the supplier is called exactly one time
* following one or several calls to
* {@link #getOrCompute(java.util.function.Supplier) } by any number of
* threads. Thus, the method is thread safe.
*
* @param supplier to use for supplying a new value. Must never return null.
* @return the value of the Lazy instance
* @throws NullPointerException if the supplier returns a {@code null} value
* or if the supplier itself is null.
*/
T getOrCompute(Supplier supplier);
}