ConstructorGenerator.java
package dev.orne.test.rnd.params;
/*-
* #%L
* Orne Test Generators
* %%
* Copyright (C) 2022 Orne Developments
* %%
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as
* published by the Free Software Foundation, either version 3 of the
* License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Lesser Public License for more details.
*
* You should have received a copy of the GNU General Lesser Public
* License along with this program. If not, see
* <http://www.gnu.org/licenses/lgpl-3.0.html>.
* #L%
*/
import java.lang.reflect.Constructor;
import javax.validation.constraints.NotNull;
import org.apiguardian.api.API;
import org.apiguardian.api.API.Status;
import dev.orne.test.rnd.GenerationException;
import dev.orne.test.rnd.Generators;
/**
* Generator that calls a constructor with generated parameters to
* generate values of the target type.
*
* @author <a href="mailto:wamphiry@orne.dev">(w) Iker Hernaez</a>
* @version 1.0, 2022-12
* @param <T> The type of generated values
* @since 0.1
*/
@API(status=Status.EXPERIMENTAL, since="0.1")
public class ConstructorGenerator<T>
extends ExecutableGenerator<T> {
/**
* Creates a new instance.
*
* @param constructor The constructor to call
* @param paramGenerators The parameter generators
*/
protected ConstructorGenerator(
final @NotNull Constructor<T> constructor,
final @NotNull TargetedGenerator<?>[] paramGenerators) {
super(constructor.getDeclaringClass(), constructor, paramGenerators);
}
/**
* Creates a new instance that will call the specified constructor.
*
* @param <T> The type of the generated instance
* @param constructor The constructor to call
* @return The created generator
*/
public static <T> ConstructorGenerator<T> of(
final @NotNull Constructor<T> constructor) {
final TargetedGenerator<?>[] generators = new TargetedGenerator<?>[constructor.getParameterCount()];
for (int i = 0; i < generators.length; i++) {
generators[i] = Generators.forParameter(constructor, i);
}
return new ConstructorGenerator<>(constructor, generators);
}
/**
* {@inheritDoc}
*/
@Override
@SuppressWarnings("unchecked")
public Constructor<T> getExecutable() {
return (Constructor<T>) super.getExecutable();
}
/**
* {@inheritDoc}
*/
@Override
protected @NotNull T generate(
final Object[] params) {
try {
return getExecutable().newInstance(params);
} catch (Exception e) {
throw new GenerationException("Error generating new instance", e);
}
}
}