Hibernate Mapping Package

Question

I\'m using Hibernate Annotations.

In all my model classes I annotate like this:

@Entity
@Table
public class SomeModelClass {
//
}

M

Answer 1

If you do not want to use spring or any other library, you can achieve that like this. Same approach as luke's but without Reflections library

import org.hibernate.SessionFactory;
import org.hibernate.boot.registry.StandardServiceRegistryBuilder;
import org.hibernate.cfg.Configuration;
import org.hibernate.service.ServiceRegistry;

import javax.persistence.Entity;
import javax.tools.FileObject;
import javax.tools.JavaFileObject;
import javax.tools.StandardJavaFileManager;
import javax.tools.StandardLocation;
import javax.tools.ToolProvider;
import java.io.File;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Collections;
import java.util.regex.Pattern;
import java.util.stream.Collectors;
import java.util.stream.StreamSupport;

public class SessionFactoryWrapper {

    private final SessionFactory sessionFactory;

    public SessionFactoryWrapper(final String...packagesToScan) {
        this.sessionFactory = this.createSessionFactory(packagesToScan);
    }

    private SessionFactory createSessionFactory(final String[] packagesToScan) {
        final Configuration configuration = new Configuration();
        configuration.configure(); // Reads hibernate.cfg.xml from classpath

        for (String packageToScan : packagesToScan) {
            this.getEntityClasses(packageToScan).stream().forEach( configuration::addAnnotatedClass);
        }

        final ServiceRegistry serviceRegistry = new StandardServiceRegistryBuilder().applySettings(configuration.getProperties()).build();
        return configuration.buildSessionFactory(serviceRegistry);
    }

    private Collection getEntityClasses(final String pack) {
        final StandardJavaFileManager fileManager = ToolProvider.getSystemJavaCompiler().getStandardFileManager(null, null, null);
        try {
            return StreamSupport.stream(fileManager.list(StandardLocation.CLASS_PATH, pack, Collections.singleton(JavaFileObject.Kind.CLASS), false).spliterator(), false)
                    .map(FileObject::getName)
                    .map(name -> {
                        try {
                            final String[] split = name
                                    .replace(".class", "")
                                    .replace(")", "")
                                    .split(Pattern.quote(File.separator));

                            final String fullClassName = pack + "." + split[split.length - 1];
                            return Class.forName(fullClassName);
                        } catch (ClassNotFoundException e) {
                            throw new RuntimeException(e);
                        }

                    })
                    .filter(aClass -> aClass.isAnnotationPresent(Entity.class))
                    .collect(Collectors.toCollection(ArrayList::new));
        } catch (IOException e) {
            throw new RuntimeException(e);
        }
    }

    public SessionFactory getSessionFactory() {
        return sessionFactory;
    }
}