三、Hibernate基础配置 1、如果在Annotation中,类名与真是的数据库中的表名不同,可以使用增加@Table(name=数据库中的表名)的方式使其对应。此时,如果数据库中有这个表名则会对应上,如果没有这个表,则会生成这个表。同样的,在XXX.hbm.xml中,也可以配置
三、Hibernate基础配置1、如果在Annotation中,类名与真是的数据库中的表名不同,可以使用增加@Table(name="数据库中的表名")的方式使其对应。此时,如果数据库中有这个表名则会对应上,如果没有这个表,则会生成这个表。同样的,在XXX.hbm.xml中,也可以配置增加响应的Tabel=tableName的配置。
2、所有没有定义注解的属性等价于在其上面添加了@Basic注解。
3、属性名与字段名不对应的情况,使用@Column(name="数据表的字段名")的方式使其相对应。
4、不需要persistence的字段可以使用@Transient的方式进行注解。这样该字段就不会写入数据表中。在xml中,不进行配置就可以了。
5、属性是时间格式的情况下,默认会将年月日时分秒全部存入。可以使用@Temporal(TemporalType.DATE)的形式使其只存入日期,当然,还可以使其存入其他的日期格式。
6、Hibernate映射的类型。Hibernate会自动将jav【本文来自鸿网互联 (http://www.68idc.cn)】a类型的数据转换为对应的sql类型
7、枚举类型的映射。如果指定的字段名含有枚举类型,则在数据表中也可以实现相应的存储。@Enumerated(EnumType.ORDINAL)的方式使得存入的枚举类型为int类型,@Enumerated(EnumType.STRING)的方式使得存入的值为varchar类型。
8、Annotation建议写在get()方法上,而不是写在属性上。
小实验:
修改Teacher.java
package com.zgy.hibernate.model; import java.util.Date; import javax.persistence.Column; import javax.persistence.Entity; import javax.persistence.EnumType; import javax.persistence.Enumerated; import javax.persistence.Id; import javax.persistence.Table; import javax.persistence.Temporal; import javax.persistence.TemporalType; import javax.persistence.Transient; @Entity @Table(name="_teacher") public class Teacher { private int id; private String name; private String title; private String address; private String wifeName; private Date birth; private ZhiCheng zhiCheng; @Id public int getId() { return id; } public void setId(int id) { this.id = id; } @Column(name="_name") public String getName() { return name; } public void setName(String name) { this.name = name; } public String getTitle() { return title; } public void setTitle(String title) { this.title = title; } public String getAddress() { return address; } public void setAddress(String address) { this.address = address; } public String getWifeName() { return wifeName; } public void setWifeName(String wifeName) { this.wifeName = wifeName; } @Temporal(TemporalType.DATE) public Date getBirth() { return birth; } public void setBirth(Date birth) { this.birth = birth; } @Enumerated(EnumType.STRING) public ZhiCheng getZhiCheng() { return zhiCheng; } public void setZhiCheng(ZhiCheng zhiCheng) { this.zhiCheng = zhiCheng; } } 修改test下的TeacherTesting.java package com.zgy.hibernate.model; import static org.junit.Assert.*; import java.util.Date; import org.hibernate.Session; import org.hibernate.SessionFactory; import org.hibernate.cfg.AnnotationConfiguration; import org.hibernate.cfg.Configuration; import org.junit.AfterClass; import org.junit.BeforeClass; import org.junit.Test; public class TeacherTesting { public static SessionFactory sf = null; @BeforeClass public static void beforeClass(){ sf = new AnnotationConfiguration().configure().buildSessionFactory(); } @Test public void test() { Teacher t = new Teacher(); t.setId(5); t.setName("t5"); t.setTitle("高级"); t.setAddress("北京"); t.setBirth(new Date()); t.setZhiCheng(ZhiCheng.A); Session session = sf.openSession(); session.beginTransaction(); session.save(t); session.getTransaction().commit(); session.close(); } @AfterClass public static void afterClass(){ sf.close(); } }

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