com.blazebit.persistence.Criteria Maven / Gradle / Ivy
/*
* Copyright 2014 - 2020 Blazebit.
*
* 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.blazebit.persistence;
import com.blazebit.persistence.spi.CriteriaBuilderConfiguration;
import com.blazebit.persistence.spi.CriteriaBuilderConfigurationProvider;
import java.util.Iterator;
import java.util.ServiceLoader;
/**
* Bootstrap class that is used to obtain a {@linkplain CriteriaBuilder} instance.
*
* @author Christian Beikov
* @since 1.0.0
*/
public class Criteria {
private Criteria() {
}
/**
* Returns the first {@linkplain CriteriaBuilderConfigurationProvider} that is found.
*
* @return The first {@linkplain CriteriaBuilderConfigurationProvider} that is found
*/
public static CriteriaBuilderConfigurationProvider getDefaultProvider() {
ServiceLoader serviceLoader = ServiceLoader.load(CriteriaBuilderConfigurationProvider.class);
Iterator iterator = serviceLoader.iterator();
if (iterator.hasNext()) {
return iterator.next();
}
throw new IllegalStateException("No CriteriaBuilderConfigurationProvider found on the class path. Please check if a valid implementation is on the class path.");
}
/**
* Uses the default {@linkplain CriteriaBuilderConfigurationProvider} and invokes
* {@link CriteriaBuilderConfigurationProvider#createConfiguration() }.
*
* @return A new criteria builder configuration
*/
public static CriteriaBuilderConfiguration getDefault() {
return getDefaultProvider().createConfiguration(DefaultPackageOpener.INSTANCE);
}
}