通过在某个包中添加所有类,在Hibernate中添加带注释的类。 JAVA

时间:2011-11-14 14:09:54

标签: java hibernate

有没有办法循环(例如,通过for)所有类在某个包中? 我必须在addAnnotatedClass(Class c)AnnotationConfiguration。 这样做:

    AnnotationConfiguration annotationConfiguration.addAnnotatedClass(AdditionalInformation.class);
    annotationConfiguration.addAnnotatedClass(AdditionalInformationGroup.class);
    annotationConfiguration.addAnnotatedClass(Address.class);
    annotationConfiguration.addAnnotatedClass(BankAccount.class);
    annotationConfiguration.addAnnotatedClass(City.class);
    //et cetera

我的所有表都在Tables.Informations个包中。

4 个答案:

答案 0 :(得分:13)

正如评论中所提到的,使用AnnotationConfiguration API无法加载包中所有类的功能。以下是您可以使用所述API执行的一些操作(请注意,“addPackage”方法仅读取包元数据,例如package-info.java类中的元数据,它不会加载包中的所有类):

http://docs.jboss.org/hibernate/annotations/3.5/reference/en/html/ch01.html

sessionFactory = new AnnotationConfiguration()
                    .addPackage("test.animals") //the fully qualified package name
                    .addAnnotatedClass(Flight.class)
                    .addAnnotatedClass(Sky.class)
                    .addAnnotatedClass(Person.class)
                    .addAnnotatedClass(Dog.class)
                    .addResource("test/animals/orm.xml")
                    .configure()
                    .buildSessionFactory();

答案 1 :(得分:6)

以下代码遍历指定包中的所有类,并列出使用“@Entity”注释的类。这些类中的每一个都被添加到您的Hibernate工厂配置中,而不必明确地列出它们。

public static void main(String[] args) throws URISyntaxException, IOException, ClassNotFoundException {
    try {
        Configuration configuration = new Configuration().configure();
        for (Class cls : getEntityClassesFromPackage("com.example.hib.entities")) {
            configuration.addAnnotatedClass(cls);
        }
        sessionFactory = configuration.buildSessionFactory();
    } catch (Throwable ex) {
        System.err.println("Failed to create sessionFactory object." + ex);
        throw new ExceptionInInitializerError(ex);
    }
}

public static List<Class<?>> getEntityClassesFromPackage(String packageName) throws ClassNotFoundException, IOException, URISyntaxException {
    List<String> classNames = getClassNamesFromPackage(packageName);
    List<Class<?>> classes = new ArrayList<Class<?>>();
    for (String className : classNames) {
        Class<?> cls = Class.forName(packageName + "." + className);
        Annotation[] annotations = cls.getAnnotations();

        for (Annotation annotation : annotations) {
            System.out.println(cls.getCanonicalName() + ": " + annotation.toString());
            if (annotation instanceof javax.persistence.Entity) {
                classes.add(cls);
            }
        }
    }

    return classes;
}

public static ArrayList<String> getClassNamesFromPackage(String packageName) throws IOException, URISyntaxException, ClassNotFoundException {
    ClassLoader classLoader = Thread.currentThread().getContextClassLoader();
    ArrayList<String> names = new ArrayList<String>();

    packageName = packageName.replace(".", "/");
    URL packageURL = classLoader.getResource(packageName);

    URI uri = new URI(packageURL.toString());
    File folder = new File(uri.getPath());
    File[] files = folder.listFiles();
    for (File file: files) {
        String name = file.getName();
        name = name.substring(0, name.lastIndexOf('.'));  // remove ".class"
        names.add(name);
    }

    return names;
}

有用的参考:https://stackoverflow.com/a/7461653/7255

答案 2 :(得分:2)

有一个很好的开源软件包,称为“ org.reflections”。您可以在这里找到它:https://github.com/ronmamo/reflections

使用该软件包,您可以扫描以下实体:

Reflections reflections = new Reflections("Tables.Informations");
Set<Class<?>> importantClasses = reflections.getTypesAnnotatedWith(Entity.class);
for (Class<?> clazz : importantClasses) {
    configuration.addAnnotatedClass(clazz);
}

答案 3 :(得分:1)

您可以使用 LocalSessionFactoryBuilder 构建会话工厂,以便指定 scanPackages 属性。

SessionFactory sessionFactory = new LocalSessionFactoryBuilder(hikariDataSource())
        .scanPackages("com.animals.entities")
        .addProperties(properties)
        .buildSessionFactory();