软件简介

Morphia 是一个轻量级的类型安全的 Java 类库，用来将在
MongoDB 和 Java 对象之间进行映射。

@Entity("employees")  
class Employee {  
  @Id ObjectId id; // auto-generated, if not set (see ObjectId)  
  String firstName, lastName; // value types are automatically persisted  
  Long salary = null; // only non-null values are stored

  @Embedded Address address;

  @Reference Employee manager; // refs are stored*, and loaded automatically  
  @Reference List<Employee> underlings; // interfaces are supported

  @Serialized EncryptedReviews; // stored in one binary field   
   
  @Property("started") Date startDate; //fields can be renamed  
  @Property("left")Date endDate;

  @Indexed boolean active = false; //fields can be indexed for better performance  
  @NotSaved string readButNotStored; //fields can read, but not saved  
  @Transient int notStored; //fields can be ignored (load/save)  
  transient boolean stored = true; //not @Transient, will be ignored by Serialization/GWT for example.

  //Lifecycle methods -- Pre/PostLoad, Pre/PostSave...  
  @PostLoad void postLoad(DBObject dbObj) { ... }  
}