每次开发基本上都是使用mybatis，对于hibernate，估计也忘了差不多。今天来重温了一下hibernate的配置实现。
第一步，肯定是配置文件：
/**
* Created by alan on 2018/6/18.
*/
@Configuration
public class HibernateConfig {
private String driver = "com.mysql.jdbc.Driver";
private String url = "jdbc:mysql://localhost:3306/test?useUnicode=true&characterEncoding=UTF-8";
private String username = "root";
private String password = "root";
public HibernateConfig(){
}
@Bean
public BasicDataSource dataSource(){
BasicDataSource dataSource = new BasicDataSource();
dataSource.setDriverClassName(driver);
dataSource.setUrl(url);
dataSource.setUsername(username);
dataSource.setPassword(password);
dataSource.setInitialSize(5);
dataSource.setMaxIdle(100);
dataSource.setMaxOpenPreparedStatements(100);
dataSource.setCacheState(true);
dataSource.setMaxTotal(1000);
dataSource.setTestWhileIdle(true);
dataSource.setValidationQuery("SELECT 1");
dataSource.setTimeBetweenEvictionRunsMillis(3600000L);
dataSource.setMinEvictableIdleTimeMillis(1800000L);
dataSource.setTestOnBorrow(true);
return dataSource;
}
@Bean
public LocalContainerEntityManagerFactoryBean entityManagerFactory(){
HibernateJpaVendorAdapter adapter = new HibernateJpaVendorAdapter();
adapter.setDatabasePlatform("org.hibernate.dialect.MySQL5InnoDBDialect");
Properties properties = new Properties();
properties.setProperty("hibernate.dialect","org.hibernate.dialect.MySQL5InnoDBDialect");
properties.setProperty("hibernate.show_sql","true");
properties.setProperty("hibernate.format_sql","true");
properties.setProperty("hibernate.auto","update");
LocalContainerEntityManagerFactoryBean factoryBean = new LocalContainerEntityManagerFactoryBean();
factoryBean.setPersistenceUnitName("SpringJPA");
factoryBean.setJpaVendorAdapter(adapter);
factoryBean.setDataSource(this.dataSource());
factoryBean.setSharedCacheMode(SharedCacheMode.ENABLE_SELECTIVE);
factoryBean.setValidationMode(ValidationMode.NONE);
/**
* scan @Entity
*/
factoryBean.setPackagesToScan("com.example.demo.model","com.example.demo.repository");
//factoryBean.setMappingResources("com/example/demo/repository/resource/User.hbm.xml");
factoryBean.setJpaProperties(properties);
return factoryBean;
}
@Bean
public PlatformTransactionManager platformTransactionManager(){
return new JpaTransactionManager(this.entityManagerFactory().getObject());
}
@Bean
public PersistenceAnnotationBeanPostProcessor persistenceAnnotationBeanPostProcessor(){
return new PersistenceAnnotationBeanPostProcessor();
}
}
配置文件由dateSource、LocalContainerEntityManagerFactoryBean、PlatformTransactionManager组成，改有的都有了，现在来实现DAO层，emmmmm，本人比较懒，直接在service层里直接写代码了，如下：
public class TestByHibernateServiceImpl {
private static final Logger logger = LoggerFactory.getLogger(TestByHibernateServiceImpl.class);
@PersistenceContext
private EntityManager manager;
@Resource
private LxUserMapper userMapper;
public TestByHibernateServiceImpl() {
}
public List<LxUserModel> getAll() {
Query query = manager.createNativeQuery("SELECT * FROM lx_user ORDER BY id DESC",LxUserModel.class);
return query.getResultList();
}
public LxUserModel getRow() {
// return manager.createQuery("SELECT a FROM LxUserModel a ORDER BY id DESC",LxUserModel.class).setMaxResults(1).getSingleResult();
return userMapper.getRow();
}
public int add(LxUserModel userModel) {
manager.persist(userModel);
return userModel.getId();
}
哇塞，跟昨天写的那篇文章比，正篇肯真简短，没错大部分代码都是EntityManager去实现了，很多人包括我都因为懒，不去写自己的DAO实现，而去用开源的，如果有时间还是建议自己实现或看一下EntityManager的原理。
/**
* Created by alan on 2018/6/18.
*/
@Repository
public interface LxUserMapper extends JpaRepository<LxUserModel,Integer> {
@Query(value = "SELECT * FROM lx_user ORDER BY id DESC limit 1",nativeQuery = true)
LxUserModel getRow();
}
下面提供一个例子，在真实场景中，查询数据可是千奇百怪，所以按照自己的思维封装了几个通用的方法，当然啦，肯定是使用了EntityManager:
/**
* Created by alan.luo on 2017/10/22.
*/
public abstract class AbstractDefaultRepository<E extends Serializable> extends AbstractDefaultBaseRepository<E> {
@PersistenceContext
private EntityManager manager;
/**
* get all the data.
* @param page
* @param where
* @param order
* @param isDesc
* @return
*/
@Override
public List<E> getAll(int page, List<PredicatePojo> where, String order, boolean isDesc) {
CriteriaBuilder builder = this.manager.getCriteriaBuilder();
CriteriaQuery<E> query = builder.createQuery(this.entityClass);
Root<E> root = query.from(this.entityClass);
CriteriaQuery<E> select = query.select(root);
if (order != null && !"".equals(order)){
if (isDesc){
select.orderBy(builder.desc(root.get(order)));
}else {
select.orderBy(builder.asc(root.get(order)));
}
}
select.where(getListPredicate(where,builder,root));
TypedQuery<E> typedQuery = this.manager.createQuery(select);
typedQuery.setFirstResult((page - 1) * ConstantInit.PAGE_SIZE);
typedQuery.setMaxResults(ConstantInit.PAGE_SIZE);
return typedQuery.getResultList();
}
/**
* search all the data.
* @param page
* @param condition
* @param order
* @param isDesc
* @return
*/
@Override
public PagePojo<E> search(int page, List<PredicatePojo> condition, String order, boolean isDesc){
CriteriaBuilder builder = this.manager.getCriteriaBuilder();
CriteriaQuery<Long> query = builder.createQuery(Long.class);
Root<E> root = query.from(this.entityClass);
CriteriaQuery<Long> select = query.select(builder.count(root));
select.where(getListPredicate(condition,builder,root));
long total = this.manager.createQuery(select).getSingleResult();
PagePojo<E> pages = new PagePojo<E>((long) page,total);
pages.setList(this.getAll(page,condition,order,isDesc));
return pages;
}
@Override
public E getRowById(int id) {
return this.manager.find(this.entityClass,id);
}
@Override
public void add(E o) {
this.manager.persist(o);
}
@Override
public void update(E o) {
this.manager.merge(o);
}
@Override
public void remove(E o) {
this.manager.remove(o);
}
@Override
public int removeById(int id) {
CriteriaBuilder builder = this.manager.getCriteriaBuilder();
CriteriaDelete<E> q = builder.createCriteriaDelete(this.entityClass);
return this.manager
.createQuery(q.where(builder.equal(q.from(this.entityClass).get("id"),id)))
.executeUpdate();
}
/**
*
* List<PredicatePojo> where = new ArrayList<>();
* where.add(new PredicatePojo("id","81", Criteria.lt));
* where.add(new PredicatePojo("age","10", Criteria.gt));
*
* List<PredicatePojo> where = new ArrayList<>();
* if (userName != null){
* userName = "%" + userName + "%";
* List<PredicatePojo> like = new ArrayList<>();
* like.add(new PredicatePojo("username",userName, Criteria.like));
* like.add(new PredicatePojo("mobile",userName, Criteria.like));
* like.add(new PredicatePojo("email",userName, Criteria.like));
*
* PredicatePojo pojo = new PredicatePojo();
* pojo.setLikeObj(like);
* pojo.setCriteria(Criteria.like);
* where.add(pojo);
* }
*
*
*
* parser predicate.
* @param where
* @param builder
* @param root
* @return
*/
protected Predicate[] getListPredicate(List<PredicatePojo> where,CriteriaBuilder builder,Root<E> root){
Predicate[] predicates = new Predicate[where.size()];
Predicate[] like;
if (where != null && where.size() > 0){
Predicate p = null;
for (int i = 0; i < where.size();i++){
Criteria ca = where.get(i).getCriteria();
switch (ca){
case equal:
p = builder.equal(root.get(where.get(i).getKey()),where.get(i).getValue());
break;
case notEqual:
p = builder.notEqual(root.get(where.get(i).getKey()),where.get(i).getValue());
break;
case isNull:
p = builder.isNull(root.get(where.get(i).getKey()));
break;
case isNotNull:
p = builder.isNotNull(root.get(where.get(i).getKey()));
break;
case gt:
p = builder.gt(root.get(where.get(i).getKey()),Double.valueOf(where.get(i).getValue()));
break;
case lt:
p = builder.lt(root.get(where.get(i).getKey()),Double.valueOf(where.get(i).getValue()));
break;
case ge:
p = builder.ge(root.get(where.get(i).getKey()),Double.valueOf(where.get(i).getValue()));
break;
case le:
p = builder.le(root.get(where.get(i).getKey()),Double.valueOf(where.get(i).getValue()));
break;
case isFalse:
p = builder.isFalse(root.get(where.get(i).getKey()));
break;
case isTrue:
p = builder.isTrue(root.get(where.get(i).getKey()));
break;
case not:
p = builder.not(root.get(where.get(i).getKey()));
break;
case like:
like = new Predicate[where.get(i).getLikeObj().size()];
for (int j = 0; j < where.get(i).getLikeObj().size();j++){
like[j] = builder.like(root.get(where.get(i).getLikeObj().get(j).getKey())
,where.get(i).getLikeObj().get(j).getValue());
}
p = builder.or(like);
break;
case notLike:
like = new Predicate[where.get(i).getLikeObj().size()];
for (int j = 0; j < where.get(i).getLikeObj().size();j++){
like[j] = builder.notLike(root.get(where.get(i).getLikeObj().get(j).getKey())
,where.get(i).getLikeObj().get(j).getValue());
}
p = builder.and(like);
break;
}
predicates[i] = p;
}
}
return predicates;
}
}
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