/*
* Copyright 2017 the original author or 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 org.gradle.api.provider;
import org.gradle.api.Incubating;
import org.gradle.api.Project;
import java.util.concurrent.Callable;
/**
* A factory for creating instances of {@code Provider} and {@code PropertyState}.
* <p>
* An instance of the factory can be injected into a task or plugin by annotating a public constructor or method with {@code javax.inject.Inject}.
*
* <pre autoTested=''>
* public class MyTask extends DefaultTask {
* // injection into a constructor
* {@literal @}javax.inject.Inject
* public MyTask(ProviderFactory providerFactory) { }
*
* // injection into a method
* {@literal @}javax.inject.Inject
* public ProviderFactory getProviderFactory() {
* throw new UnsupportedOperationException();
* }
* }
* </pre>
*
* <p>An instance of the factory is also available using {@link Project#getProviders()}</p>
*
* @since 4.0
*/
@Incubating
public interface ProviderFactory {
/**
* Creates a {@code Provider} implementation based on the provided value.
*
* @param value The {@code java.util.concurrent.Callable} use to calculate the value.
* @return The provider. Never returns null.
* @throws org.gradle.api.InvalidUserDataException If the provided value is null.
*/
<T> Provider<T> provider(Callable<T> value);
/**
* Creates a {@code PropertyState} implementation based on the provided class.
* The value returned by the property state is the default value of the standard Java data type.
* Please see <a href="https://docs.oracle.com/javase/tutorial/java/nutsandbolts/datatypes.html">Oracle's Java manual</a> for more information.
* <p>
* Any other data type than the standard Java data types returns null as default value.
*
* @param clazz The class to be used for property state.
* @return The property state. Never returns null.
* @throws org.gradle.api.InvalidUserDataException If the provided class is null.
*/
<T> PropertyState<T> property(Class<T> clazz);
}