spring-data-jpa 入门资料

• maven环境安装 

     
     
      org.springframework.data
      
     
      spring-data-jpa
      
     
      1.4.3.RELEASE
      
     
     
     
      org.hibernate.javax.persistence
      
     
      hibernate-jpa-2.1-api
      
     
      1.0.0.Draft-16
      
     
     
     
      org.hibernate
      
     
      hibernate-entitymanager
      
     
      4.2.7.SP1
      
    

spring-data-jpa下载jar会自动依赖包，包括spring framework框架包。 1.4.3.RELEASE依赖包是spring framework的版本是3.14 具体如下：   除此之外，需要手动选择jpa支持的厂商，我这里选择是hibernate。hibernate-jpa-2.1-api是指的jpa的2.1规范，hibernate-entitymanager是jpa的具体实现。 加入数据库驱动包及spring test

     
     
      com.h2database
      
     
      h2
      
     
      1.3.174
      
     
     
     
      org.springframework
      
     
      spring-test
      
     
      3.1.4.RELEASE
      
     
      test
      
    

最终，pom文件如下：

     
      
      
       org.springframework.data
       
      
       spring-data-jpa
       
      
       1.4.3.RELEASE
       
      
      
      
       org.hibernate.javax.persistence
       
      
       hibernate-jpa-2.1-api
       
      
       1.0.0.Draft-16
       
      
      
      
       org.hibernate
       
      
       hibernate-entitymanager
       
      
       4.2.7.SP1
       
      
      
      
       com.h2database
       
      
       h2
       
      
       1.3.174
       
      
      
      
       org.springframework
       
      
       spring-test
       
      
       3.1.4.RELEASE
       
      
       test
       
       
    

• 配置 

   在src/main/resources/META-INF目录下，新建persistence.xml，内容如下：

在src/main/resources,新建infrastructure.xml，内容如下：

在src/main/resources,新建log4j.xml，内容如下：

• 开发 

    User类：

package org.springframework.data.jpa.example.domain; import javax.persistence.Column; import javax.persistence.Entity; import javax.persistence.NamedQuery; import org.springframework.data.jpa.domain.AbstractPersistable; /**  * Sample user class.  *   * @author Oliver Gierke  * @author Thomas Darimont  */ @Entity @NamedQuery(name = "User.findByTheUsersName", query = "from User u where u.username = ?1") public class User extends AbstractPersistable
    
      { private static final long serialVersionUID = -2952735933715107252L; @Column(unique = true) private String username; private String firstname; private String lastname; public User() { this(null); } /** * Creates a new user instance. */ public User(Long id) { this.setId(id); } /** * Returns the username. *  * @return */ public String getUsername() { return username; } /** * @param username the username to set */ public void setUsername(String username) { this.username = username; } /** * @return the firstname */ public String getFirstname() { return firstname; } /** * @param firstname the firstname to set */ public void setFirstname(String firstname) { this.firstname = firstname; } /** * @return the lastname */ public String getLastname() { return lastname; } /** * @param lastname the lastname to set */ public void setLastname(String lastname) { this.lastname = lastname; } }
    

SimpleUserRepository类：

package org.springframework.data.jpa.example.repository.simple; import java.util.List; import org.springframework.data.jpa.example.domain.User; import org.springframework.data.jpa.repository.Query; import org.springframework.data.repository.CrudRepository; import org.springframework.data.repository.query.Param; /**  * Simple repository interface for {@link User} instances. The interface is used to declare so called query methods,  * methods to retrieve single entities or collections of them.  *   * @author Oliver Gierke  * @author Thomas Darimont  */ public interface SimpleUserRepository extends CrudRepository
    
      { /** * Find the user with the given username. This method will be translated into a query using the * {@link javax.persistence.NamedQuery} annotation at the {@link User} class. *  * @param lastname * @return */ User findByTheUsersName(String username); /** * Find all users with the given lastname. This method will be translated into a query by constructing it directly * from the method name as there is no other query declared. *  * @param lastname * @return */ List
     
       findByLastname(String lastname); /** * Returns all users with the given firstname. This method will be translated into a query using the one declared in * the {@link Query} annotation declared one. *  * @param firstname * @return */ @Query("select u from User u where u.firstname = ?") List
      
        findByFirstname(String firstname); /** * Returns all users with the given name as first- or lastname. Makes use of the {@link Param} annotation to use named * parameters in queries. This makes the query to method relation much more refactoring safe as the order of the * method parameters is completely irrelevant. *  * @param name * @return */ @Query("select u from User u where u.firstname = :name or u.lastname = :name") List
       
         findByFirstnameOrLastname(@Param("name") String name); }
       
      
     
    

加入spring配置：

• 测试 

AbstractSimpleUserRepositoryTests类：

package org.springframework.data.jpa.example.repository.simple; import static org.junit.Assert.*; import java.util.List; import org.junit.Before; import org.junit.Test; import org.junit.runner.RunWith; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.data.jpa.example.domain.User; import org.springframework.test.context.junit4.SpringJUnit4ClassRunner; import org.springframework.transaction.annotation.Transactional; /**  * Intergration test showing the basic usage of {@link SimpleUserRepository}.  *   * @author Oliver Gierke  * @author Thomas Darimont  */ @RunWith(SpringJUnit4ClassRunner.class) //@Transactional public abstract class AbstractSimpleUserRepositoryTests { @Autowired SimpleUserRepository repository; User user; @Before public void setUp() { user = new User(); user.setUsername("foobar"); user.setFirstname("firstname"); user.setLastname("lastname"); } @Test public void findSavedUserById() {     user = repository.save(user); user = repository.findByTheUsersName("foobar"); // assertEquals(user, repository.findOne(user.getId())); } @Test public void findSavedUserByLastname() throws Exception { // user = repository.save(user); List
    
      users = repository.findByLastname("lastname"); // assertNotNull(users); // assertTrue(users.contains(user)); } @Test public void findByFirstnameOrLastname() throws Exception { // user = repository.save(user); List
     
       users = repository.findByFirstnameOrLastname("lastname"); // assertTrue(users.contains(user)); } }
     
    

XmlConfigSimpleUserRepositoryTests类：

package org.springframework.data.jpa.example.repository.simple; import org.springframework.test.context.ContextConfiguration; /**  * @author Thomas Darimont  */ @ContextConfiguration(locations = "/simple-repository-context.xml") public class XmlConfigSimpleUserRepositoryTests extends AbstractSimpleUserRepositoryTests {}

• 结果