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yangfuchao418：
楼主你这个实在太simple了。你可以用htmlunit。
commons-httpclient 的使用(模拟浏览器) -
fengfeng925：
linliangyi2007 写道sunson468 写道有那 ...
用反射注解实现的ORM(一看就明白的那种) -
pclfs1983：
楼上说的很有道理
用反射注解实现的ORM(一看就明白的那种) -
linliangyi2007：
楼主的工作还是很值得实践一次的，尤其是学习研究阶段。写过和看过 ...
用反射注解实现的ORM(一看就明白的那种) -
linliangyi2007：
sunson468 写道有那么多开源的成熟的架构，除非非常有必 ...
用反射注解实现的ORM(一看就明白的那种)
例子:
Entity->
package com.hibernate.model;
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;
}
}
package com.hibernate.model;
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")
}
)
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;
}
@Id
@GeneratedValue
public int getId() {
return id;
}
public String getTitle() {
return title;
}
public void setCategory(Category category) {
this.category = category;
}
public void setId(int id) {
this.id = id;
}
public void setTitle(String title) {
this.title = title;
}
}
package com.hibernate.model;
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;
@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;
}
@ManyToOne
public Topic getTopic() {
return topic;
}
public void setTopic(Topic topic) {
this.topic = topic;
}
}
package com.hibernate.model;
public class MsgInfo {
private int id;
private String topicName;
private String cont;
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 getCategoryName() {
return categoryName;
}
public String getCont() {
return cont;
}
public int getId() {
return id;
}
public String getTopicName() {
return topicName;
}
public void setCategoryName(String categoryName) {
this.categoryName = categoryName;
}
public void setCont(String cont) {
this.cont = cont;
}
public void setId(int id) {
this.id = id;
}
public void setTopicName(String topicName) {
this.topicName = topicName;
}
}
测试->
package com.hibernate.test;
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;
import com.hibernate.model.Category;
import com.hibernate.model.Msg;
import com.hibernate.model.MsgInfo;
import com.hibernate.model.Topic;
public class HQLTest {
private static SessionFactory sf = null;
@BeforeClass
public static void beforeClass() {
// new SchemaExport(new
// AnnotationConfiguration().configure()).create(false, true);
sf = new AnnotationConfiguration().configure().buildSessionFactory();
}
@AfterClass
public static void afterClass() {
sf.close();
}
@Test
public void testSchemaExport() {
new SchemaExport(new AnnotationConfiguration().configure()).create(
false, true);
}
public static void main(String[] args) {
new HQLTest().testSchemaExport();
}
// 保存
@Test
public void testSave() {
Session session = sf.getCurrentSession();
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.setTopic(t);
m.setCont("m" + i);
session.save(m);
}
session.getTransaction().commit();
}
@Test
public void testHQL_01() {
Session s = sf.getCurrentSession();
s.beginTransaction();
Query q = s.createQuery("from Category");
List<Category> categorys = (List<Category>) q.list();
for (Category c : categorys) {
System.out.println(c.getName());
}
s.getTransaction().commit();
}
@Test
public void testHQL_02() {
Session s = sf.getCurrentSession();
s.beginTransaction();
Query q = s.createQuery("from Category c where c.name> 'c5'");
List<Category> categorys = (List<Category>) q.list();
for (Category c : categorys) {
System.out.println(c.getName());
}
s.getTransaction().commit();
}
@Test
public void testHQL_03() {
Session s = sf.getCurrentSession();
s.beginTransaction();
Query q = s.createQuery("from Category c order by c.name desc");
List<Category> categorys = (List<Category>) q.list();
for (Category c : categorys) {
System.out.println(c.getName());
}
s.getTransaction().commit();
}
@Test
public void testHQL_04() {
Session s = sf.getCurrentSession();
s.beginTransaction();
Query q = s.createQuery("select distinct c from Category c order by c.name desc");
List<Category> categorys = (List<Category>) q.list();
for (Category c : categorys) {
System.out.println(c.getName());
}
s.getTransaction().commit();
}
@Test
public void testHQL_05(){
Session s = sf.getCurrentSession();
s.beginTransaction();
Query q = s.createQuery("from Category c where c.id > :min and c.id < :max")
.setInteger("min", 2)
.setInteger("max", 8)
;
List<Category> categorys = (List<Category>) q.list();
for (Category c : categorys) {
System.out.println(c.getName());
}
s.getTransaction().commit();
}
@Test
public void testHQL_06(){
Session s = sf.getCurrentSession();
s.beginTransaction();
Query q = s.createQuery("from Category c where c.id > ? and c.id < ?")
.setParameter(0, 2)
.setParameter(1, 8)
;
List<Category> categorys = (List<Category>) q.list();
for (Category c : categorys) {
System.out.println(c.getName());
}
s.getTransaction().commit();
}
//分页
@Test
public void testHQL_07(){
Session s = sf.getCurrentSession();
s.beginTransaction();
Query q = s.createQuery("from Category c order by c.name asc");
q.setMaxResults(4);
q.setFirstResult(2);
List<Category> categorys = (List<Category>) q.list();
for (Category c : categorys) {
System.out.println(c.getId() + "-" + c.getName());
}
s.getTransaction().commit();
}
@Test
public void testHQL_08(){
Session s = sf.getCurrentSession();
s.beginTransaction();
Query q = s.createQuery("select c.id, c.name from Category c order by c.name desc");
List<Object[]> cs = (List<Object[]>)q.list();
for(Object[] o : cs){
System.out.println(o[0] + "--"+ o[1]);
}
s.getTransaction().commit();
}
//设定fetch type 为lazy后将不会有第二条sql语句
@Test
public void testHQL_09(){
Session s = sf.getCurrentSession();
s.beginTransaction();
Query q = s.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());
}
s.getTransaction().commit();
}
@Test
public void testHQL_011(){
Session s = sf.getCurrentSession();
s.beginTransaction();
Query q = s.createQuery("from Msg m where m.topic.category.id = 1");
for(Object o : q.list()){
Msg m = (Msg)o;
System.out.println(m.getCont());
}
s.getTransaction().commit();
}
//DTO VO
@Test
public void testHQL_012(){
Session s = sf.getCurrentSession();
s.beginTransaction();
Query q = s.createQuery("select new com.hibernate.model.MsgInfo(m.id,m.cont,m.topic.title,m.topic.category.name) from Msg m") ;
for(Object o : q.list()){
MsgInfo m = (MsgInfo)o;
System.out.println(m.getCont());
}
s.getTransaction().commit();
}
@Test
public void testHQL_013(){
Session s = sf.getCurrentSession();
s.beginTransaction();
Query q = s.createQuery("select t.title, c.name from Topic t join t.category c");
for(Object o :q.list()){
Object[] m = (Object[])o;
System.out.println(m[0]+"---"+ m[1]);
}
s.getTransaction().commit();
}
@Test
public void testHQL_014(){
Session s = sf.getCurrentSession();
s.beginTransaction();
Query q = s.createQuery("from Msg m where m = :m");
Msg m = new Msg();
m.setId(1);
q.setParameter("m", m);
Msg mResult = (Msg)q.uniqueResult();
System.out.println(mResult.getCont());
s.getTransaction().commit();
}
@Test
public void testHQL_015(){
Session s = sf.getCurrentSession();
s.beginTransaction();
Query q = s.createQuery("select count(*) from Msg m");
long count = (Long)q.uniqueResult();
System.out.println(count);
s.getTransaction().commit();
}
@Test
public void testHQL_016(){
Session s = sf.getCurrentSession();
s.beginTransaction();
Query q = s.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]);
s.getTransaction().commit();
}
@Test
public void testHQL_017(){
Session s = sf.getCurrentSession();
s.beginTransaction();
Query q = s.createQuery("from Msg m where m.id between 3 and 5");
for(Object o : q.list()){
Msg m = (Msg)o;
System.out.println(m.getCont());
}
s.getTransaction().commit();
}
@Test
public void testHQL_018(){
Session s = sf.getCurrentSession();
s.beginTransaction();
Query q = s.createQuery("from Msg m where m.id in(4,5,6)");
for(Object o : q.list()){
Msg m = (Msg)o;
System.out.println(m.getCont());
}
s.getTransaction().commit();
}
@Test
public void testHQL_020(){
Session s = sf.getCurrentSession();
s.beginTransaction();
Query q = s.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());
}
s.getTransaction().commit();
}
@Test
public void testHQL_019(){
Session s = sf.getCurrentSession();
s.beginTransaction();
Query q = s.createQuery("from Msg m where m.cont is not null ");
for(Object o : q.list()){
Msg m = (Msg)o;
System.out.println(m.getCont());
}
s.getTransaction().commit();
}
@Test
public void testHQL_021(){
Session s = sf.getCurrentSession();
s.beginTransaction();
Query q = s.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());
}
s.getTransaction().commit();
}
@Test
public void testHQL_022(){
Session s = sf.getCurrentSession();
s.beginTransaction();
Query q = s.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());
}
s.getTransaction().commit();
}
@Test
public void testHQL_023(){
Session s = sf.getCurrentSession();
s.beginTransaction();
Query q = s.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[] b = (Object[])o;
System.out.println(b[0]+"--"+b[1]+"--"+b[2]+"--"+b[3]+"--"+b[4]+"--");
}
s.getTransaction().commit();
}
@Test
public void testHQL_024(){
Session s = sf.getCurrentSession();
s.beginTransaction();
Query q = s.createQuery("select abs(t.id), sqrt(t.id),mod(t.id,2) from Topic t");
for(Object o : q.list()){
Object[] b = (Object[])o;
System.out.println(b[0]+"--"+b[1]+"--"+b[2]+"--");
}
s.getTransaction().commit();
}
@Test
public void testHQL_025(){
Session s = sf.getCurrentSession();
s.beginTransaction();
Query q = s.createQuery("select current_date,current_time,current_timestamp,t.id from Topic t");
for(Object o : q.list()){
Object[] b = (Object[])o;
System.out.println(b[0]+"--"+b[1]+"--"+b[2]+"--"+b[3]);
}
s.getTransaction().commit();
}
@Test
public void testHQL_026(){
Session s = sf.getCurrentSession();
s.beginTransaction();
Query q = s.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());
}
s.getTransaction().commit();
}
@Test
public void testHQL_027(){
Session s = sf.getCurrentSession();
s.beginTransaction();
Query q = s.createQuery("select t.title ,count(*) from Topic t group by t.title");
for(Object o : q.list()){
Object[] b = (Object[])o;
System.out.println(b[0]+"--"+b[1]);
}
s.getTransaction().commit();
}
@Test
public void testHQL_028(){
Session s = sf.getCurrentSession();
s.beginTransaction();
Query q = s.createQuery("select t.title ,count(*) from Topic t group by t.title having count(*) >=1");
for(Object o : q.list()){
Object[] b = (Object[])o;
System.out.println(b[0]+"--"+b[1]);
}
s.getTransaction().commit();
}
@Test
public void testHQL_029(){
Session s = sf.getCurrentSession();
s.beginTransaction();
Query q = s.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());
}
s.getTransaction().commit();
}
@Test
public void testHQL_030(){
Session s = sf.getCurrentSession();
s.beginTransaction();
Query q = s.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());
}
s.getTransaction().commit();
}
@Test
public void testHQL_031(){
Session s = sf.getCurrentSession();
s.beginTransaction();
Query q = s.createQuery("from Topic t where not exists(select m.id from Msg m where m.topic = t.id )");
for(Object o : q.list()){
Topic t = (Topic)o;
System.out.println(t.getTitle());
}
s.getTransaction().commit();
}
@Test
public void testHQL_032(){
Session s = sf.getCurrentSession();
s.beginTransaction();
Query q = s.createQuery("update Topic t set t.title = upper(t.title)");
q.executeUpdate();
q = s.createQuery("from Topic");
for(Object o : q.list()){
Topic t = (Topic)o;
System.out.println(t.getTitle());
}
s.createQuery("update Topic t set t.title = lower(t.title)").executeUpdate();
s.getTransaction().commit();
}
@Test
public void testHQL_033(){
Session s = sf.getCurrentSession();
s.beginTransaction();
Query q = s.getNamedQuery("topic.selectCertainTopic");
q.setParameter("id", 5);
Topic t = (Topic)q.uniqueResult();
System.out.println(t.getTitle());
s.getTransaction().commit();
}
//NativeSQL
@Test
public void testHQL_034(){
Session s = sf.getCurrentSession();
s.beginTransaction();
Query q = s.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());
}
s.getTransaction().commit();
}
}
//QBC*********************************************
@Test
public void testQBC(){
Session s = sf.getCurrentSession();
s.beginTransaction();
Criteria c = s.createCriteria(Topic.class)
.add(Restrictions.gt("id", 2))
.add(Restrictions.lt("id", 8))
.add(Restrictions.like("title", "t_"));
for(Object o: c.list()){
Topic t = (Topic)o;
System.out.println(t.getTitle());
}
s.getTransaction().commit();
}
//QBE************************************************
@Test
public void testQBE(){
Session s = sf.getCurrentSession();
s.beginTransaction();
Topic tExample = new Topic();
tExample.setTitle("T_");
Example e = Example.create(tExample ).ignoreCase().enableLike();
Criteria c = s.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());
}
s.getTransaction().commit();
}
- Example.rar (5.1 MB)
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Hibernate---乐观锁/悲观锁
2010-06-13 00:32 1183背景知识: 1.事务（Transa ... -
Hibernate-------一级缓存/二级缓存/查询缓存
2010-06-12 23:19 991例子: model: @Entity //@Bat ... -
Hibernate - List与Iterator缓存问题
2010-06-12 18:37 17441.默认情况下,list不会利用一级缓存，iterator会利 ... -
Hibernate N+1问题
2010-06-12 17:07 10731.n+1问题:当查询多一方时，默认会把对应一的一端也查出来. ... -
(6)hibernate CURD
2010-06-02 10:38 12191. 获取session,SessionFactory sf ... -
(5)hibernate ID生成策略
2010-06-01 14:22 01.xml方式 <id name="id& ... -
(4)hibernate 用EJB3注解进行映射
2010-05-31 21:35 8621.每一个持久化POJO类都是一个实体bean,这可以通过在类 ... -
(3)hibernate配置
2010-05-31 20:47 7841.hibernate3.3.2日志配置,默认采用slf处理日 ... -
(2)hibernate annotations使用
2010-05-30 23:43 8971.在hibernate3.3.2的hibernate-ann ... -
(1)hibernate3.3.2准备工作
2010-05-30 22:48 11091.加入所需要的包 下载hibernate3.3.2的发行 ...
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7. **查询语言**: Hibernate支持多种查询语言，包括原生SQL、HQL（Hibernate Query Language）、EJB QL、QBC（Query By Example）和QBE（Query By Example）。HQL更接近面向对象的查询，而EJB QL是Java EE的一部分，...
Criteria 查询机制主要包括 QBE（Query By Example）、QBC（Query By Criteria）和 HQL（Hibernate Query Language）三种方式。 QBE（Query By Example） QBE 是一种基于示例的查询机制，它可以根据一个示例对象来...
在Java的持久化框架Hibernate中，Criteria API提供了一种动态构造SQL查询的方式，它允许开发者在运行时构建灵活的查询，而无需预先编写HQL（Hibernate Query Language）语句。Criteria API提供了丰富的功能，包括...
本文主要探讨Hibernate中的查询语言，包括面向对象的查询语言HQL，QueryBy Criteria (QBC)，Query By Example (QBE)，以及原生SQL的使用。 1. **大小写敏感性** HQL查询语句对Java类和属性名称的大小写敏感，而...
Hibernate Query Language（HQL）是Hibernate的面向对象的查询语言，类似于SQL，但操作对象和属性而非表和列。以下是一个HQL示例： ```java String hql = "select s.name, avg(s.age) from Student s group by s....
查询对象，HQL Criteria 1.hibernate提供的更面向对象的一种查询方式。 准备工作: 1.java中的POJO对象存在 2.数据库，表得存在 3.hibernate的配置文件(hibernate.cfg.xml)得存在 4.POJO.hbm.xml文件存在 5....