29 @GeneratedValue
30 private long id;
31
32 /**
33 * Annotates the field to carry a TIMESTAMP value in the database column.
34 * The column name is different than the default value of timestamp
35 * because many databases will reserve that word.
36 *
37 * The field is immutable by application (no setter method) and set on
38 * construction with current time.
39 */
40 @Temporal(TemporalType.TIMESTAMP)
41 @Column(name="createdOn")
42 private Date timestamp;
43
44 /**
45 * Does not annotate but the field will be persisted nevertheless by
46 * convention of String and primitive types being persistent by default.
47 */
48 private String body;
49
50 protected Message() {
51 this("");
52 }
53
54 public Message(String body) {
55 timestamp = new Date();
56 this.body = (body == null) ? "" : body;
57 }
58
59 public long getId() {
60 return id;
61 }
62
63 public String getBody() {
64 return body;
65 }
66
67 public Date getTimestamp() {
68 return timestamp;
69 }
70 } 因為我們使用了O-R映射注釋表示Message類的實例與數據庫表和列之間的映射關系（或者說是哪個域值能夠作為Message實例的主標識符），所以JPA依賴關系已經移入這個Java類中。這些映射信息可以移到一個單獨的orm.xml中，從而使這個類恢復Pure Old Java Object (POJO)狀態并完善這種不明確的更接近域對象模型的方法。
編碼前的測試
JUnit測試用例通過JNDI查找與服務進行交互并檢驗兩個服務方法返回的是否為預期的結果。
文章來源于領測軟件測試網 http://www.kjueaiud.com/
