Hibernate使用xml配置持久化類
阿新 • • 發佈：2019-01-24
Hibernate通過物件關係對映，使用持久化類代替傳統的sql語句對資料庫進行操作（通俗說就是把資料表變成一個實體類來看待和操作）。其中，持久化類可以使用
1.配置對應的hbm.xml(關係對映配置檔案)來對映持久化實體類。
2.直接在持久化實體類以註解方式配置。
前期工作：
一、匯入Hibernate相關依賴包（包括本人使用的mysql驅動包和c3p0連線池依賴包）：
二、建立事例表與資料：
xml配置持久化類：
一、首先，先在Hibernate.cfg.xml配置Hibernate啟動相關配置項：
<?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE hibernate-configuration PUBLIC "-//Hibernate/Hibernate Configuration DTD 3.0//EN" "http://hibernate.sourceforge.net/hibernate-configuration-3.0.dtd"> <hibernate-configuration> <session-factory > <!-- mysql資料庫驅動 --> <property name="hibernate.connection.driver_class">com.mysql.jdbc.Driver</property> <!-- mysql資料庫名稱 --> <property name="hibernate.connection.url">jdbc:mysql://localhost:3306/world</property> <!-- 資料庫的登陸使用者名稱 --> <property name="hibernate.connection.username">root</property> <!-- 資料庫的登陸密碼 --> <property name="hibernate.connection.password">1988419</property> <!-- 配置方言為每一種資料庫提供特殊sql適配--> <property name="hibernate.dialect">org.hibernate.dialect.MySQLDialect</property> <!-- c3p0連線池配置 --> <property name="hibernate.connection.provider_class">org.hibernate.connection.C3P0ConnectionProvider</property> <!-- 連線池最大連線 --> <property name="hibernate.c3p0.max_size">10</property> <!-- 連線池最小連線 --> <property name="hibernate.c3p0.min_size">1</property> <!-- 連線池超時時長（毫秒） --> <property name="hibernate.c3p0.timeout">5000</property> <!-- 指定連線池最大快取多少Statment物件 --> <property name="hibernate.c3p0.max_statment">50</property> <!-- 空閒檢測週期（毫秒） --> <property name="hibernate.c3p0.idle_test_period">3000</property> <!-- 連線池一次增加的連線數 --> <property name="hibernate.c3p0.acquire_increment">5</property> <!-- 每次都驗證連線是否可用 --> <property name="hibernate.c3p0.validate">true</property> <!-- 是否在控制檯輸出sql語句 --> <property name="hibernate.show_sql">true</property> <!-- 使用xml配置時，指定持久化類xml的路徑 --> <mapping resource="org/lcwben/Student.hbm.xml"></mapping> <!-- 使用註解持久化類配置時，指定持久化類.java檔案配置 --> <!-- <mapping class="org.lcwben.Student" /> --> </session-factory> </hibernate-configuration>
二、建立持久化實體類：
public class Student { private Integer uid; private String uname; private Date regtime; private Integer status; private Integer score; private Integer classes; //所有成員變數的getter與setter public Integer getUid() { return uid; } public void setUid(Integer uid) { this.uid = uid; } public String getUname() { return uname; } public void setUname(String uname) { this.uname = uname; } public Date getRegtime() { return regtime; } public void setRegtime(Date regtime) { this.regtime = regtime; } public Integer getStatus() { return status; } public void setStatus(Integer status) { this.status = status; } public Integer getScore() { return score; } public void setScore(Integer score) { this.score = score; } public Integer getClasses() { return classes; } public void setClasses(Integer classes) { this.classes = classes; } //。。。。。。。。。。。。。。。。。。。。。。。 }
三、配置關聯對映xml
<?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN" "http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd"> <hibernate-mapping> <class name="org.lcwben.Student" table="test_stu"> <!-- 主鍵使用自增（increment）選項 --> <id name="uid" column="uid"> <generator class="increment"/> </id> <property name="uname"/> <property name="regtime"/> <property name="status"/> <property name="score"/> <property name="classes"/> </class> </hibernate-mapping>
四、JUnit測試
public class Client {
private static SessionFactory sf;
//利用靜態塊初始化連線池
static {
//用Configuration類初始化hibernate.cfg.xml的配置項
Configuration cfg = new Configuration().configure();
ServiceRegistry sr = new ServiceRegistryBuilder().applySettings(cfg.getProperties()).buildServiceRegistry();
sf = cfg.buildSessionFactory(sr);
}
//增
@Test
public void testCreate() {
Session session = null;
try {
//開啟session
session = sf.openSession();
//開啟事務管理器
session.beginTransaction();
Student stu1 = new Student();
stu1.setUname("hib1");
stu1.setRegtime(new Date());
stu1.setStatus(1);
stu1.setScore(75);
stu1.setClasses(4);
session.save(stu1);
//從session物件取出事務管理器，提交事務；
session.getTransaction().commit();
} catch (Exception e) {
e.printStackTrace();
//出異常時對事務進行事務回滾
session.getTransaction().rollback();
} finally {
if(session!=null){
session.close();
}
}
}
//刪
@Test
public void delete() {
Session session = null;
try {
session = sf.openSession();
session.beginTransaction();
Student stu1 = new Student();
stu1.setUid(12);
stu1.setUname("hib1");
stu1.setRegtime(new Date());
stu1.setStatus(1);
stu1.setScore(75);
stu1.setClasses(4);
session.delete(stu1);
session.getTransaction().commit();
} catch (Exception e) {
e.printStackTrace();
session.getTransaction().rollback();
} finally {
if(session!=null) {
session.close();
}
}
}
//全量查詢
@Test
public void selectAll() {
Session session = null;
List<Student> stus = null;
try {
session = sf.openSession();
session.beginTransaction();
//注意：HQL中的表名並非資料庫中的表名，而是對應對映物件類的類名！！！
Query query1 = session.createQuery("from Student");
stus = query1.list();
for (Student stu : stus) {
System.out.println(stu.getUid()+" "+stu.getUname()+" "+stu.getRegtime()+" "+stu.getStatus()+" "+stu.getScore()+" "+stu.getClasses());
}
} catch (Exception e) {
e.printStackTrace();
} finally {
if(session!=null) {
session.close();
}
}
}
//條件查詢
@Test
public void selectOne() {
Session session = null;
try {
session = sf.openSession();
Query query = session.createQuery("from Student where uid=:id");
query.setInteger("id", 3);
Student stu = (Student)query.uniqueResult();
System.out.println(stu.getUid()+" "+stu.getUname()+" "+stu.getRegtime()+" "+stu.getStatus()+" "+stu.getScore()+" "+stu.getClasses());
} catch (Exception e) {
e.printStackTrace();
} finally {
if(session!=null) {
session.close();
}
}
}
//改
@Test
public void update () {
Session session = null;
try {
session = sf.openSession();
session.beginTransaction();
String hql = "update Student set uname=:name where uid=:id";
Query qry = session.createQuery(hql);
qry.setString("name", "lcwhbm1");
qry.setInteger("id", 4);
qry.executeUpdate();
session.getTransaction().commit();
} catch (Exception e) {
e.printStackTrace();
session.getTransaction().rollback();
} finally {
if (session!=null) {
session.close();
}
}
}
//改
@Test
public void update2 () {
Session session = null;
try {
session = sf.openSession();
session.beginTransaction();
/*使用load(持久化類物件, 主鍵值)的方式直接獲得條件所指的物件，
* 代替了select... where pk=...的形式，不需要寫sql語句就可以實現條件查詢的功能。
*/
Student stu = (Student)session.load(Student.class, 4);
//然後使用持久化類的setter可以對該條資料進行修改！
stu.setUname("benhbm2");
session.getTransaction().commit();
} catch (Exception e) {
e.printStackTrace();
session.getTransaction().rollback();
} finally {
if (session!=null) {
session.close();
}
}
}三月 08, 2017 2:35:48 下午 org.hibernate.engine.transaction.internal.TransactionFactoryInitiator initiateService
INFO: HHH000399: Using default transaction strategy (direct JDBC transactions)
三月 08, 2017 2:35:48 下午 org.hibernate.hql.internal.ast.ASTQueryTranslatorFactory <init>
INFO: HHH000397: Using ASTQueryTranslatorFactory
Hibernate: select student0_.uid as uid1_0_, student0_.uname as uname2_0_, student0_.regtime as regtime3_0_, student0_.status as status4_0_, student0_.score as score5_0_, student0_.classes as classes6_0_ from test_stu student0_
1 lcwben1 2017-01-18 00:00:00.0 0 60 1
2 lcwben2 2017-01-18 00:00:00.0 1 67 1
3 lcwben3 2017-01-19 00:00:00.0 1 51 3
4 benhbm2 2017-01-19 00:00:00.0 0 78 3
5 lcwben5 2017-01-19 00:00:00.0 0 80 3
6 lcwben6 2017-01-22 00:00:00.0 1 97 2
7 lcwben7 2017-01-23 00:00:00.0 0 73 1
8 lcwben8 2017-01-25 00:00:00.0 1 48 2
9 lcwben9 2017-01-28 00:00:00.0 1 100 3
10 lcwben10 2017-01-31 00:00:00.0 0 92 3至於註解式配置持久化類，由於篇幅所限，另開一篇文章(點選開啟連結)。