在功能方面是本地SQL>HQL>EJBQL>QBC>QBE

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假想一個BBS。

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板塊：

package com.bjsxt.hibernate;

import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;

@Entity
public class Category {
??? private int id;
??? private String name;
??? @Id
??? @GeneratedValue
??? public int getId() {
??????? return id;
??? }
??? public void setId(int id) {
??????? this.id = id;
??? }
??? public String getName() {
??????? return name;
??? }
??? public void setName(String name) {
??????? this.name = name;
??? }
}

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主題：

package com.bjsxt.hibernate;

import java.util.ArrayList;
import java.util.Date;
import java.util.List;

import javax.persistence.Entity;
import javax.persistence.FetchType;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.ManyToOne;
import javax.persistence.NamedQueries;
import javax.persistence.NamedQuery;
import javax.persistence.OneToMany;

@Entity
@NamedQueries(
??????? {
??????????? @NamedQuery(name="topic.selectCertainTopic", query="from Topic t where t.id = :id")
??????? }
??????? )
/*
@NamedNativeQueries(
??????? {
??????????? @NamedNativeQuery(name="topic.select2_5Topic", query="select * from topic limit 2, 5")
??????? }
??????? )
*/

public class Topic {
??? private int id;
??? private String title;
??? private Category category;
??? private Date createDate;
??? private List<Msg> msgs = new ArrayList<Msg>();
??? @OneToMany(mappedBy="topic")
??? public List<Msg> getMsgs() {
???????
??????? return msgs;
??? }
??? public void setMsgs(List<Msg> msgs) {
??????? this.msgs = msgs;
??? }
??? public Date getCreateDate() {
??????? return createDate;
??? }
??? public void setCreateDate(Date createDate) {
??????? this.createDate = createDate;
??? }
??? @ManyToOne(fetch=FetchType.LAZY)
??? public Category getCategory() {
??????? return category;
??? }
??? public void setCategory(Category category) {
??????? this.category = category;
??? }
??? @Id
??? @GeneratedValue
??? public int getId() {
??????? return id;
??? }
??? public void setId(int id) {
??????? this.id = id;
??? }
??? public String getTitle() {
??????? return title;
??? }
??? public void setTitle(String title) {
??????? this.title = title;
??? }
???
}

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回復：

package com.bjsxt.hibernate;

import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.ManyToOne;

@Entity
public class Msg {
??? private int id;
??? private String cont;
??? private Topic topic;
??? @ManyToOne
??? public Topic getTopic() {
??????? return topic;
??? }
??? public void setTopic(Topic topic) {
??????? this.topic = topic;
??? }
??? @Id
??? @GeneratedValue
??? public int getId() {
??????? return id;
??? }
??? public void setId(int id) {
??????? this.id = id;
??? }
???
??? public String getCont() {
??????? return cont;
??? }
??? public void setCont(String cont) {
??????? this.cont = cont;
??? }
???
}

?

EJBQL語句中創建對象的類：

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package com.bjsxt.hibernate;

import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.ManyToOne;

public class MsgInfo { //VO DTO Value Object username p1 p2 UserInfo->User->DB
??? private int id;
??? private String cont;
??? private String topicName;
??? private String categoryName;
??? public MsgInfo(int id, String cont, String topicName, String categoryName) {
??????? super();
??????? this.id = id;
??????? this.cont = cont;
??????? this.topicName = topicName;
??????? this.categoryName = categoryName;
??? }
??? public String getTopicName() {
??????? return topicName;
??? }
??? public void setTopicName(String topicName) {
??????? this.topicName = topicName;
??? }
??? public String getCategoryName() {
??????? return categoryName;
??? }
??? public void setCategoryName(String categoryName) {
??????? this.categoryName = categoryName;
??? }
??? public int getId() {
??????? return id;
??? }
??? public void setId(int id) {
??????? this.id = id;
??? }
???
??? public String getCont() {
??????? return cont;
??? }
??? public void setCont(String cont) {
??????? this.cont = cont;
??? }
???
}

?

EJBQL測試類1：

package com.bjsxt.hibernate;

import java.util.Date;

import java.util.List;

import org.hibernate.Query;

import org.hibernate.Session;

import org.hibernate.SessionFactory;

import org.hibernate.cfg.AnnotationConfiguration;

import org.hibernate.tool.hbm2ddl.SchemaExport;

import org.junit.AfterClass;

import org.junit.BeforeClass;

import org.junit.Test;

public class HibernateQLTest {

private static SessionFactory sf;

@BeforeClass

public static void beforeClass() {

sf = new AnnotationConfiguration().configure().buildSessionFactory();

}

@AfterClass

public static void afterClass() {

sf.close();

}

@Test

public void testSchemaExport() {

new SchemaExport(new AnnotationConfiguration().configure()).create(false, true);

}

@Test

public void testSave() {

Session session = sf.openSession();

session.beginTransaction();

for(int i=0; i<10; i++) {

Category c = new Category();

c.setName("c" + i);

session.save(c);

}

for(int i=0; i<10; i++) {

Category c = new Category();

c.setId(1);

Topic t = new Topic();

t.setCategory(c);

t.setTitle("t" + i);

t.setCreateDate(new Date());

session.save(t);

}

for(int i=0; i<10; i++) {

Topic t = new Topic();

t.setId(1);

Msg m = new Msg();

m.setCont("m" + i);

m.setTopic(t);

session.save(m);

}

session.getTransaction().commit();

session.close();

}

@Test

public void testHQL_01() {

Session session = sf.openSession();

session.beginTransaction();

Query q = session.createQuery("from Category");//類名

List<Category> categories = (List<Category>)q.list();

for(Category c : categories) {

System.out.println(c.getName());

}

session.getTransaction().commit();

session.close();

}

@Test

public void testHQL_02() {

Session session = sf.openSession();

session.beginTransaction();

Query q = session.createQuery("from Category c where c.name > 'c5'");

List<Category> categories = (List<Category>)q.list();

for(Category c : categories) {

System.out.println(c.getName());

}

session.getTransaction().commit();

session.close();

}

@Test

public void testHQL_03() {

Session session = sf.openSession();

session.beginTransaction();

Query q = session.createQuery("from Category c order by c.name desc");

List<Category> categories = (List<Category>)q.list();

for(Category c : categories) {

System.out.println(c.getName());

}

session.getTransaction().commit();

session.close();

}

@Test

public void testHQL_04() {

Session session = sf.openSession();

session.beginTransaction();

//distinct

Query q = session.createQuery("select distinct c from Category c order by c.name desc");

List<Category> categories = (List<Category>)q.list();

for(Category c : categories) {

System.out.println(c.getName());

}

session.getTransaction().commit();

session.close();

}

@Test

public void testHQL_05() {

Session session = sf.openSession();

session.beginTransaction();

/*Query q = session.createQuery("from Category c where c.id > :min and c.id < :max");

//q.setParameter("min", 2);

//q.setParameter("max", 8);

q.setInteger("min", 2);

q.setInteger("max", 8);*/

Query q = session.createQuery("from Category c where c.id > :min and c.id < :max")//冒號是個占位符

.setInteger("min", 2)

.setInteger("max", 8);

List<Category> categories = (List<Category>)q.list();

for(Category c : categories) {

System.out.println(c.getId() + "-" + c.getName());

}

session.getTransaction().commit();

session.close();

}

@Test

public void testHQL_06() {

Session session = sf.openSession();

session.beginTransaction();

Query q = session.createQuery("from Category c where c.id > ? and c.id < ?");

q.setParameter(0, 2)

.setParameter(1, 8);

// q.setParameter(1, 8);

List<Category> categories = (List<Category>)q.list();

for(Category c : categories) {

System.out.println(c.getId() + "-" + c.getName());

}

session.getTransaction().commit();

session.close();

}

//分頁

@Test

public void testHQL_07() {

Session session = sf.openSession();

session.beginTransaction();

Query q = session.createQuery("from Category c order by c.name desc");

q.setMaxResults(4);//最多4條

q.setFirstResult(2);//從下標為2的那條開始，包括那條

List<Category> categories = (List<Category>)q.list();

for(Category c : categories) {

System.out.println(c.getId() + "-" + c.getName());

}

session.getTransaction().commit();

session.close();

}

@Test

public void testHQL_08() {

Session session = sf.openSession();

session.beginTransaction();

Query q = session.createQuery("select c.id, c.name from Category c order by c.name desc");

List<Object[]> categories = (List<Object[]>)q.list();//每一條當成一個對象數組

for(Object[] o : categories) {

System.out.println(o[0] + "-" + o[1]);

}

session.getTransaction().commit();

session.close();

}

//設定fetch type 為lazy后將不會有第二條sql語句

@Test

public void testHQL_09() {

Session session = sf.openSession();

session.beginTransaction();

Query q = session.createQuery("from Topic t where t.category.id = 1");

List<Topic> topics = (List<Topic>)q.list();

for(Topic t : topics) {

System.out.println(t.getTitle());

//System.out.println(t.getCategory().getName());

}

session.getTransaction().commit();

session.close();

}

//設定fetch type 為lazy后將不會有第二條sql語句

@Test

public void testHQL_10() {

Session session = sf.openSession();

session.beginTransaction();

Query q = session.createQuery("from Topic t where t.category.id = 1");

List<Topic> topics = (List<Topic>)q.list();

for(Topic t : topics) {

System.out.println(t.getTitle());

}

session.getTransaction().commit();

session.close();

}

@Test

public void testHQL_11() {

Session session = sf.openSession();

session.beginTransaction();

Query q = session.createQuery("from Msg m where m.topic.category.id = 1");

for(Object o : q.list()) {

Msg m = (Msg)o;

System.out.println(m.getCont());

}

session.getTransaction().commit();

session.close();

}

//了解即可

//VO Value Object

//DTO data transfer object

@Test

public void testHQL_12() {

Session session = sf.openSession();

session.beginTransaction();

Query q = session.createQuery("select new com.bjsxt.hibernate.MsgInfo(m.id, m.cont, m.topic.title, m.topic.category.name) from Msg");

for(Object o : q.list()) {

MsgInfo m = (MsgInfo)o;

System.out.println(m.getCont());

}

session.getTransaction().commit();

session.close();

}

//動手測試left right join

//為什么不能直接寫Category名，而必須寫t.category

//因為有可能存在多個成員變量（同一個類），需要指明用哪一個成員變量的連接條件來做連接

@Test

public void testHQL_13() {

Session session = sf.openSession();

session.beginTransaction();

Query q = session.createQuery("select t.title, c.name from Topic t join t.category c "); //join Category c

for(Object o : q.list()) {

Object[] m = (Object[])o;

System.out.println(m[0] + "-" + m[1]);

}

session.getTransaction().commit();

session.close();

}

//學習使用uniqueResult

@Test

public void testHQL_14() {

Session session = sf.openSession();

session.beginTransaction();

Query q = session.createQuery("from Msg m where m = :MsgToSearch "); //不重要

Msg m = new Msg();

m.setId(1);

q.setParameter("MsgToSearch", m);

Msg mResult = (Msg)q.uniqueResult();

System.out.println(mResult.getCont());

session.getTransaction().commit();

session.close();

}

@Test

public void testHQL_15() {

Session session = sf.openSession();

session.beginTransaction();

Query q = session.createQuery("select count(*) from Msg m");

long count = (Long)q.uniqueResult();

System.out.println(count);

session.getTransaction().commit();

session.close();

}

@Test

public void testHQL_16() {

Session session = sf.openSession();

session.beginTransaction();

Query q = session.createQuery("select max(m.id), min(m.id), avg(m.id), sum(m.id) from Msg m");

Object[] o = (Object[])q.uniqueResult();

System.out.println(o[0] + "-" + o[1] + "-" + o[2] + "-" + o[3]);

session.getTransaction().commit();

session.close();

}

@Test

public void testHQL_17() {

Session session = sf.openSession();

session.beginTransaction();

Query q = session.createQuery("from Msg m where m.id between 3 and 5");

for(Object o : q.list()) {

Msg m = (Msg)o;

System.out.println(m.getId() + "-" + m.getCont());

}

session.getTransaction().commit();

session.close();

}

@Test

public void testHQL_18() {

Session session = sf.openSession();

session.beginTransaction();

Query q = session.createQuery("from Msg m where m.id in (3,4, 5)");

for(Object o : q.list()) {

Msg m = (Msg)o;

System.out.println(m.getId() + "-" + m.getCont());

}

session.getTransaction().commit();

session.close();

}

//is null 與 is not null

@Test

public void testHQL_19() {

Session session = sf.openSession();

session.beginTransaction();

Query q = session.createQuery("from Msg m where m.cont is not null");

for(Object o : q.list()) {

Msg m = (Msg)o;

System.out.println(m.getId() + "-" + m.getCont());

}

session.getTransaction().commit();

session.close();

}

public static void main(String[] args) {

beforeClass();

}

}

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?

EJBQL測試類2:

package com.bjsxt.hibernate;

import java.util.Date;
import java.util.List;

import org.hibernate.Query;
import org.hibernate.SQLQuery;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.cfg.AnnotationConfiguration;
import org.hibernate.tool.hbm2ddl.SchemaExport;
import org.junit.AfterClass;
import org.junit.BeforeClass;
import org.junit.Test;

public class HibernateQLTest {
??? private static SessionFactory sf;
???
??? @BeforeClass
??? public static void beforeClass() {
??????? sf = new AnnotationConfiguration().configure().buildSessionFactory();
??? }
??? @AfterClass
??? public static void afterClass() {
??????? sf.close();
??? }
???
??? @Test
??? public void testSchemaExport() {
??????? new SchemaExport(new AnnotationConfiguration().configure()).create(false, true);
??? }
???
??? @Test
??? public void testSave() {
??????? Session session = sf.openSession();
??????? session.beginTransaction();
???????
??????? for(int i=0; i<10; i++) {
??????????? Category c = new Category();
??????????? c.setName("c" + i);
??????????? session.save(c);
??????? }
???????
??????? for(int i=0; i<10; i++) {
??????????? Category c = new Category();
??????????? c.setId(1);
??????????? Topic t = new Topic();
??????????? t.setCategory(c);
??????????? t.setTitle("t" + i);
??????????? t.setCreateDate(new Date());
??????????? session.save(t);
???????????
??????? }
???????
??????? for(int i=0; i<10; i++) {
???????????
??????????? Topic t = new Topic();
??????????? t.setId(1);
??????????? Msg m = new Msg();
??????????? m.setCont("m" + i);
??????????? m.setTopic(t);
??????????? session.save(m);
???????????
??????? }
???????
???????
???????
???????
??????? session.getTransaction().commit();
??????? session.close();
??? }
???
??? //is empty and is not empty
??? @Test
??? public void testHQL_20() {
??????? Session session = sf.openSession();
??????? session.beginTransaction();
??????? Query q = session.createQuery("from Topic t where t.msgs is empty");
???????
??????? for(Object o : q.list()) {
??????????? Topic t = (Topic)o;
??????????? System.out.println(t.getId() + "-" + t.getTitle());
??????? }
??????? session.getTransaction().commit();
??????? session.close();
???????
??? }
???
??? @Test
??? public void testHQL_21() {
??????? Session session = sf.openSession();
??????? session.beginTransaction();
??????? Query q = session.createQuery("from Topic t where t.title like '%5'");
???????
??????? for(Object o : q.list()) {
??????????? Topic t = (Topic)o;
??????????? System.out.println(t.getId() + "-" + t.getTitle());
??????? }
??????? session.getTransaction().commit();
??????? session.close();
???????
??? }
???
??? @Test
??? public void testHQL_22() {
??????? Session session = sf.openSession();
??????? session.beginTransaction();
??????? Query q = session.createQuery("from Topic t where t.title like '_5'");
???????
??????? for(Object o : q.list()) {
??????????? Topic t = (Topic)o;
??????????? System.out.println(t.getId() + "-" + t.getTitle());
??????? }
??????? session.getTransaction().commit();
??????? session.close();
???????
??? }
??? //不重要
??? @Test
??? public void testHQL_23() {
??????? Session session = sf.openSession();
??????? session.beginTransaction();
??????? Query q = session.createQuery("select lower(t.title)," +
???????????????????????????????????????????? "upper(t.title)," +
???????????????????????????????????????????? "trim(t.title)," +
???????????????????????????????????????????? "concat(t.title, '***')," +
???????????????????????????????????????????? "length(t.title)" +
???????????????????????????????????????????? " from Topic t ");
???????
??????? for(Object o : q.list()) {
??????????? Object[] arr = (Object[])o;
??????????? System.out.println(arr[0] + "-" + arr[1] + "-" + arr[2] + "-" + arr[3] + "-" + arr[4] + "-");
??????? }
??????? session.getTransaction().commit();
??????? session.close();
???????
??? }
???
??? @Test
??? public void testHQL_24() {
??????? Session session = sf.openSession();
??????? session.beginTransaction();
??????? Query q = session.createQuery("select abs(t.id)," +
???????????????????????????????????????????? "sqrt(t.id)," +
???????????????????????????????????????????? "mod(t.id, 2)" +
???????????????????????????????????????????? " from Topic t ");
???????
??????? for(Object o : q.list()) {
??????????? Object[] arr = (Object[])o;
??????????? System.out.println(arr[0] + "-" + arr[1] + "-" + arr[2] );
??????? }
??????? session.getTransaction().commit();
??????? session.close();
???????
??? }
???
??? @Test
??? public void testHQL_25() {
??????? Session session = sf.openSession();
??????? session.beginTransaction();
??????? Query q = session.createQuery("select current_date, current_time, current_timestamp, t.id from Topic t");
???????
??????? for(Object o : q.list()) {
??????????? Object[] arr = (Object[])o;
??????????? System.out.println(arr[0] + " | " + arr[1] + " | " + arr[2] + " | " + arr[3]);
??????? }
??????? session.getTransaction().commit();
??????? session.close();
???????
??? }
???
??? @Test
??? public void testHQL_26() {
??????? Session session = sf.openSession();
??????? session.beginTransaction();
??????? Query q = session.createQuery("from Topic t where t.createDate < :date");
??????? q.setParameter("date", new Date());
??????? for(Object o : q.list()) {
??????????? Topic t = (Topic)o;
??????????? System.out.println(t.getTitle());
??????? }
??????? session.getTransaction().commit();
??????? session.close();
???????
??? }
???
??? @Test
??? public void testHQL_27() {
??????? Session session = sf.openSession();
??????? session.beginTransaction();
??????? Query q = session.createQuery("select t.title, count(*) from Topic t group by t.title") ;
??????? for(Object o : q.list()) {
??????????? Object[] arr = (Object[])o;
??????????? System.out.println(arr[0] + "|" + arr[1]);
??????? }
??????? session.getTransaction().commit();
??????? session.close();
???????
??? }
???
??? @Test
??? public void testHQL_28() {
??????? Session session = sf.openSession();
??????? session.beginTransaction();
??????? Query q = session.createQuery("select t.title, count(*) from Topic t group by t.title having count(*) >= 1") ;
??????? for(Object o : q.list()) {
??????????? Object[] arr = (Object[])o;
??????????? System.out.println(arr[0] + "|" + arr[1]);
??????? }
??????? session.getTransaction().commit();
??????? session.close();
???????
??? }
???
??? @Test
??? public void testHQL_29() {
??????? Session session = sf.openSession();
??????? session.beginTransaction();
??????? Query q = session.createQuery("from Topic t where t.id < (select avg(t.id) from Topic t)") ;
??????? for(Object o : q.list()) {
??????????? Topic t = (Topic)o;
??????????? System.out.println(t.getTitle());
??????? }
??????? session.getTransaction().commit();
??????? session.close();
???????
??? }
???
??? @Test
??? public void testHQL_30() {
??????? Session session = sf.openSession();
??????? session.beginTransaction();
??????? Query q = session.createQuery("from Topic t where t.id < ALL (select t.id from Topic t where mod(t.id, 2)= 0) ") ;
??????? for(Object o : q.list()) {
??????????? Topic t = (Topic)o;
??????????? System.out.println(t.getTitle());
??????? }
??????? session.getTransaction().commit();
??????? session.close();
???????
??? }
???
??? //用in 可以實現exists的功能
??? //但是exists執行效率高
??? @Test
??? public void testHQL_31() {
??????? Session session = sf.openSession();
??????? session.beginTransaction();// t.id not in (1)
??????? Query q = session.createQuery("from Topic t where not exists (select m.id from Msg m where m.topic.id=t.id)") ;
//??????? Query q = session.createQuery("from Topic t where exists (select m.id from Msg m where m.topic.id=t.id)") ;
??????? for(Object o : q.list()) {
??????????? Topic t = (Topic)o;
??????????? System.out.println(t.getTitle());
??????? }
??????? session.getTransaction().commit();
??????? session.close();
???????
??? }
???
??? //update and delete
??? //規范并沒有說明是不是要更新persistent object，所以如果要使用，建議在單獨的trasaction中執行
???
??? @Test
??? public void testHQL_32() {
??????? Session session = sf.openSession();
??????? session.beginTransaction();
??????? Query q = session.createQuery("update Topic t set t.title = upper(t.title)") ;
???????
??????? q.executeUpdate();
??????? q = session.createQuery("from Topic");
??????? for(Object o : q.list()) {
??????????? Topic t = (Topic)o;
??????????? System.out.println(t.getTitle());
??????? }
??????? session.createQuery("update Topic t set t.title = lower(t.title)")
??????????? .executeUpdate();
??????? session.getTransaction().commit();
??????? session.close();
???????
??? }
???
??? //不重要
??? @Test
??? public void testHQL_33() {
??????? Session session = sf.openSession();
??????? session.beginTransaction();
??????? Query q = session.getNamedQuery("topic.selectCertainTopic");
??????? q.setParameter("id", 5);
??????? Topic t = (Topic)q.uniqueResult();
??????? System.out.println(t.getTitle());
??????? session.getTransaction().commit();
??????? session.close();
???????
??? }
???
??? //Native（了解）
??? @Test
??? public void testHQL_34() {
??????? Session session = sf.openSession();
??????? session.beginTransaction();
??????? SQLQuery q = session.createSQLQuery("select * from category limit 2,4").addEntity(Category.class);
??????? List<Category> categories = (List<Category>)q.list();
??????? for(Category c : categories) {
??????????? System.out.println(c.getName());
??????? }
??????? session.getTransaction().commit();
??????? session.close();
???????
??? }
???
??? @Test
??? public void testHQL_35() {
??????? //尚未實現JPA命名的NativeSQL
???????
??? }
???
??? public static void main(String[] args) {
??????? beforeClass();
??? }
}

?

?

QBC:

package com.bjsxt.hibernate;

import java.util.Date;

import org.hibernate.Criteria;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.annotations.FetchMode;
import org.hibernate.cfg.AnnotationConfiguration;
import org.hibernate.criterion.Restrictions;
import org.hibernate.tool.hbm2ddl.SchemaExport;
import org.junit.AfterClass;
import org.junit.BeforeClass;
import org.junit.Test;

public class HibernateQLTest {
??? private static SessionFactory sf;
???
??? @BeforeClass
??? public static void beforeClass() {
??????? sf = new AnnotationConfiguration().configure().buildSessionFactory();
??? }
??? @AfterClass
??? public static void afterClass() {
??????? sf.close();
??? }
???
??? @Test
??? public void testSchemaExport() {
??????? new SchemaExport(new AnnotationConfiguration().configure()).create(false, true);
??? }
???
??? @Test
??? public void testSave() {
??????? Session session = sf.openSession();
??????? session.beginTransaction();
???????
??????? for(int i=0; i<10; i++) {
??????????? Category c = new Category();
??????????? c.setName("c" + i);
??????????? session.save(c);
??????? }
???????
??????? for(int i=0; i<10; i++) {
??????????? Category c = new Category();
??????????? c.setId(1);
??????????? Topic t = new Topic();
??????????? t.setCategory(c);
??????????? t.setTitle("t" + i);
??????????? t.setCreateDate(new Date());
??????????? session.save(t);
???????????
??????? }
???????
??????? for(int i=0; i<10; i++) {
???????????
??????????? Topic t = new Topic();
??????????? t.setId(1);
??????????? Msg m = new Msg();
??????????? m.setCont("m" + i);
??????????? m.setTopic(t);
??????????? session.save(m);
???????????
??????? }
???????
???????
???????
???????
??????? session.getTransaction().commit();
??????? session.close();
??? }
???
??? //is empty and is not empty
??? @Test
??? public void testQBC() {
??????? Session session = sf.openSession();
??????? session.beginTransaction();
??????? //criterion 標準/準則/約束
??????? Criteria c = session.createCriteria(Topic.class) //from Topic
????????????????????
???????????????????? .add(Restrictions.gt("id", 2)) //greater than = id > 2
???????????????????? .add(Restrictions.lt("id", 8)) //little than = id < 8
???????????????????? .add(Restrictions.like("title", "t_"))
???????????????????? .createCriteria("category")
???????????????????? .add(Restrictions.between("id", 3, 5)) //category.id >= 3 and category.id <=5
???????????????????? ;
??????? //DetachedCriterea
??????? for(Object o : c.list()) {
??????????? Topic t = (Topic)o;
??????????? System.out.println(t.getId() + "-" + t.getTitle());
??????? }
??????? session.getTransaction().commit();
??????? session.close();
???????
??? }
???
??? public static void main(String[] args) {
??????? beforeClass();
??? }
}

?

QBE被QBC包含，是QBC的一部分：

package com.bjsxt.hibernate;

import java.util.Date;

import org.hibernate.Criteria;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.cfg.AnnotationConfiguration;
import org.hibernate.criterion.Example;
import org.hibernate.criterion.Restrictions;
import org.hibernate.tool.hbm2ddl.SchemaExport;
import org.junit.AfterClass;
import org.junit.BeforeClass;
import org.junit.Test;

public class HibernateQLTest {
??? private static SessionFactory sf;
???
??? @BeforeClass
??? public static void beforeClass() {
??????? sf = new AnnotationConfiguration().configure().buildSessionFactory();
??? }
??? @AfterClass
??? public static void afterClass() {
??????? sf.close();
??? }
???
??? @Test
??? public void testSchemaExport() {
??????? new SchemaExport(new AnnotationConfiguration().configure()).create(false, true);
??? }
???
??? @Test
??? public void testSave() {
??????? Session session = sf.openSession();
??????? session.beginTransaction();
???????
??????? for(int i=0; i<10; i++) {
??????????? Category c = new Category();
??????????? c.setName("c" + i);
??????????? session.save(c);
??????? }
???????
??????? for(int i=0; i<10; i++) {
??????????? Category c = new Category();
??????????? c.setId(1);
??????????? Topic t = new Topic();
??????????? t.setCategory(c);
??????????? t.setTitle("t" + i);
??????????? t.setCreateDate(new Date());
??????????? session.save(t);
???????????
??????? }
???????
??????? for(int i=0; i<10; i++) {
???????????
??????????? Topic t = new Topic();
??????????? t.setId(1);
??????????? Msg m = new Msg();
??????????? m.setCont("m" + i);
??????????? m.setTopic(t);
??????????? session.save(m);
???????????
??????? }
???????
???????
???????
???????
??????? session.getTransaction().commit();
??????? session.close();
??? }
???
??? //is empty and is not empty
??? //query by criteria query by example
??? @Test
??? public void testQBE() {
??????? Session session = sf.openSession();
??????? session.beginTransaction();
??????? Topic tExample = new Topic();
??????? tExample.setTitle("T_");
???????
??????? Example e = Example.create(tExample)
??????????????????? .ignoreCase().enableLike();
??????? Criteria c = session.createCriteria(Topic.class)
???????????????????? .add(Restrictions.gt("id", 2))
???????????????????? .add(Restrictions.lt("id", 8))
???????????????????? .add(e)
???????????????????? ;
????????????????????
???????
??????? for(Object o : c.list()) {
??????????? Topic t = (Topic)o;
??????????? System.out.println(t.getId() + "-" + t.getTitle());
??????? }
??????? session.getTransaction().commit();
??????? session.close();
???????
??? }
???
??? public static void main(String[] args) {
??????? beforeClass();
??? }
}

轉載于:https://www.cnblogs.com/flying607/p/3481278.html

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