Spring Data JPA 2. HelloWorld

程序员文章站 2022-04-22 08:17:01

...

Spring Data JPA HelloWorld

使用 Spring Data JPA 进行持久层开发需要的四个步骤：

配置 Spring 整合 JPA
在 Spring 配置文件中配置 Spring Data，让 Spring 为声明的接口创建代理对象。配置了 <jpa:repositories> 后，Spring 初始化容器时将会扫描 base-package 指定的包目录及其子目录，为继承 Repository 或其子接口的接口创建代理对象，并将代理对象注册为 Spring Bean，业务层便可以通过 Spring 自动封装的特性来直接使用该对象。
声明持久层的接口，该接口继承 Repository，Repository 是一个标记型接口，它不包含任何方法，如必要，Spring Data 可实现 Repository 其他子接口，其中定义了一些常用的增删改查，以及分页相关的方法。
在接口中声明需要的方法。Spring Data 将根据给定的策略（具体策略稍后讲解）来为其生成实现代码。

搭建环境

pom.xml

<?xml version="1.0" encoding="UTF-8"?>

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
  <modelVersion>4.0.0</modelVersion>

  <groupId>com.ifox.hgx</groupId>
  <artifactId>springData</artifactId>
  <version>1.0-SNAPSHOT</version>
  <packaging>war</packaging>

  <name>springData Maven Webapp</name>
  <!-- FIXME change it to the project's website -->
  <url>http://www.example.com</url>

  <properties>
    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
    <maven.compiler.source>1.8</maven.compiler.source>
    <maven.compiler.target>1.8</maven.compiler.target>
  </properties>

  <dependencies>

    <!-- https://mvnrepository.com/artifact/org.springframework/spring-context -->
    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-context</artifactId>
      <version>5.0.3.RELEASE</version>
    </dependency>

    <!-- https://mvnrepository.com/artifact/org.springframework/spring-core -->
    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-core</artifactId>
      <version>5.0.3.RELEASE</version>
    </dependency>

    <!-- https://mvnrepository.com/artifact/org.springframework/spring-beans -->
    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-beans</artifactId>
      <version>5.0.3.RELEASE</version>
    </dependency>

    <!-- https://mvnrepository.com/artifact/org.springframework/spring-web -->
    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-web</artifactId>
      <version>5.0.3.RELEASE</version>
    </dependency>

    <!-- https://mvnrepository.com/artifact/org.springframework/spring-webmvc -->
    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-webmvc</artifactId>
      <version>5.0.3.RELEASE</version>
    </dependency>

    <!-- https://mvnrepository.com/artifact/org.springframework/spring-jdbc -->
    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-jdbc</artifactId>
      <version>5.0.3.RELEASE</version>
    </dependency>

    <!-- https://mvnrepository.com/artifact/org.springframework/spring-orm -->
    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-orm</artifactId>
      <version>5.0.3.RELEASE</version>
    </dependency>


    <!-- https://mvnrepository.com/artifact/org.hibernate/hibernate-core -->
    <dependency>
      <groupId>org.hibernate</groupId>
      <artifactId>hibernate-core</artifactId>
      <version>5.2.13.Final</version>
    </dependency>

    <!-- https://mvnrepository.com/artifact/org.hibernate/hibernate-entitymanager -->
    <dependency>
      <groupId>org.hibernate</groupId>
      <artifactId>hibernate-entitymanager</artifactId>
      <version>5.2.13.Final</version>
    </dependency>

    <!-- https://mvnrepository.com/artifact/org.springframework.data/spring-data-jpa -->
    <dependency>
      <groupId>org.springframework.data</groupId>
      <artifactId>spring-data-jpa</artifactId>
      <version>2.0.3.RELEASE</version>
    </dependency>


    <!-- https://mvnrepository.com/artifact/mysql/mysql-connector-java -->
    <dependency>
      <groupId>mysql</groupId>
      <artifactId>mysql-connector-java</artifactId>
      <version>5.1.38</version>
    </dependency>

    <!-- https://mvnrepository.com/artifact/com.mchange/c3p0 -->
    <dependency>
      <groupId>com.mchange</groupId>
      <artifactId>c3p0</artifactId>
      <version>0.9.5.2</version>
    </dependency>

    <!-- https://mvnrepository.com/artifact/org.slf4j/slf4j-log4j12 -->
    <dependency>
      <groupId>org.slf4j</groupId>
      <artifactId>slf4j-log4j12</artifactId>
      <version>1.7.25</version>
      <scope>test</scope>
    </dependency>

    <dependency>
      <groupId>junit</groupId>
      <artifactId>junit</artifactId>
      <version>4.11</version>
      <scope>test</scope>
    </dependency>
  </dependencies>

配置文件: applicationContext.xml

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:context="http://www.springframework.org/schema/context" xmlns:tx="http://www.springframework.org/schema/tx"
       xmlns:jpa="http://www.springframework.org/schema/data/jpa"
       xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd   http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx.xsd http://www.springframework.org/schema/data/jpa http://www.springframework.org/schema/data/jpa/spring-jpa.xsd">


    <!-- 配置自动扫描的包 -->
    <context:component-scan base-package="com.ifox.hgx.springdata"></context:component-scan>

    <!-- 1. 配置数据源 -->
    <context:property-placeholder location="classpath:db.properties"/>

    <bean id="dataSource"
          class="com.mchange.v2.c3p0.ComboPooledDataSource">
        <property name="user" value="${jdbc.user}"></property>
        <property name="password" value="${jdbc.password}"></property>
        <property name="driverClass" value="${jdbc.driverClass}"></property>
        <property name="jdbcUrl" value="${jdbc.url}"></property>

        <!-- 配置其他属性 -->
    </bean>

    <!-- 2. 配置 JPA 的 EntityManagerFactory -->
    <bean id="entityManagerFactory"
          class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean">
        <property name="dataSource" ref="dataSource"></property>
        <property name="jpaVendorAdapter">
            <bean class="org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter"></bean>
        </property>
        <property name="packagesToScan" value="com.ifox.hgx.springdata"></property>
        <property name="jpaProperties">
            <props>
                <!-- 二级缓存相关 -->
                <!--
                <prop key="hibernate.cache.region.factory_class">org.hibernate.cache.ehcache.EhCacheRegionFactory</prop>
                <prop key="net.sf.ehcache.configurationResourceName">ehcache-hibernate.xml</prop>
                -->
                <!-- 生成的数据表的列的映射策略 -->
                <prop key="hibernate.ejb.naming_strategy">org.hibernate.cfg.ImprovedNamingStrategy</prop>
                <!-- hibernate 基本属性 -->
                <prop key="hibernate.dialect">org.hibernate.dialect.MySQL57Dialect</prop>
                <prop key="hibernate.show_sql">true</prop>
                <prop key="hibernate.format_sql">true</prop>
                <prop key="hibernate.hbm2ddl.auto">update</prop>
            </props>
        </property>
    </bean>

    <!-- 3. 配置事务管理器 -->
    <bean id="transactionManager"
          class="org.springframework.orm.jpa.JpaTransactionManager">
        <property name="entityManagerFactory" ref="entityManagerFactory"></property>
    </bean>

    <!-- 4. 配置支持注解的事务 -->
    <tx:annotation-driven transaction-manager="transactionManager"/>

    <!-- 5. 配置 SpringData -->
    <!-- 加入  jpa 的命名空间 -->
    <!-- base-package: 扫描 Repository Bean 所在的 package -->
    <jpa:repositories base-package="com.ifox.hgx.springdata"
                      entity-manager-factory-ref="entityManagerFactory"></jpa:repositories>
</beans>

数据库连接配置:db.properties

jdbc.url = jdbc:mysql://localhost:3306/JPA?useSSL=true
jdbc.user = root
jdbc.password = 123456
jdbc.driverClass = com.mysql.jdbc.Driver

log4j配置文件:log4j.properties

log4j.rootLogger=WARN, stdout, R
log4j.appender.stdout=org.apache.log4j.ConsoleAppender
log4j.appender.stdout.layout=org.apache.log4j.PatternLayout
log4j.appender.stdout.layout.ConversionPattern=%d [%t] %-5p %c - %m%n
log4j.appender.R=org.apache.log4j.RollingFileAppender
log4j.appender.R.File=example.log
log4j.appender.R.MaxFileSize=100KB
log4j.appender.R.MaxBackupIndex=1
log4j.appender.R.layout=org.apache.log4j.PatternLayout
log4j.appender.R.layout.ConversionPattern=%p %t %c - %m%n
log4j.logger.com.foo=WARN

HelloWorld

entity实体类:Person

package com.ifox.hgx.springdata.entities;

import org.springframework.format.annotation.DateTimeFormat;

import javax.persistence.*;
import java.util.Date;

@Table(name = "JPA_PERSONS")
@Entity
public class Person {
    private Integer id ;
    private String lastName ;
    private String email ;
    private Date birth ;

    @GeneratedValue(strategy = GenerationType.IDENTITY)
    @Id
    public Integer getId() {
        return id;
    }

    public void setId(Integer id) {
        this.id = id;
    }

    @Column(name = "LAST_NAME")
    public String getLastName() {
        return lastName;
    }

    public void setLastName(String lastName) {
        this.lastName = lastName;
    }

    public String getEmail() {
        return email;
    }

    public void setEmail(String email) {
        this.email = email;
    }

    @DateTimeFormat
    public Date getBirth() {
        return birth;
    }

    public void setBirth(Date birth) {
        this.birth = birth;
    }

    @Override
    public String toString() {
        return "Person{" +
                "id=" + id +
                ", lastName='" + lastName + '\'' +
                ", email='" + email + '\'' +
                ", birth=" + birth +
                '}';
    }
}

dao层:PersonRepository

package com.ifox.hgx.springdata.dao;

import com.ifox.hgx.springdata.entities.Person;
import org.springframework.data.repository.Repository;


public interface PersonRepository extends Repository<Person,Integer> {

    Person getByLastName(String lastName) ;
}

service层:PersonService

package com.ifox.hgx.springdata.service;

import com.ifox.hgx.springdata.dao.PersonRepository;
import com.ifox.hgx.springdata.entities.Person;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

@Service
public class PersonService {

    @Autowired
    private PersonRepository personRepository;

    public Person getByLastName(String lastName) {
        return personRepository.getByLastName(lastName);
    }

}

测试类:


package com.ifox.hgx.jap.spring;

import com.ifox.hgx.springdata.entities.Person;
import com.ifox.hgx.springdata.service.PersonService;
import org.junit.Test;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

import javax.sql.DataSource;
import java.sql.Connection;

public class SpringDataTest {

    private ApplicationContext applicationContext = null;
    private PersonService personService = null;

    {
        applicationContext = new ClassPathXmlApplicationContext("applicationContext.xml");
        personService = applicationContext.getBean(PersonService.class);
    }

    @Test
    public void testDataSource() throws Exception {
        DataSource dataSource = applicationContext.getBean(DataSource.class);
        Connection connection = dataSource.getConnection();
        System.out.println(connection);

    }

    @Test
    public void testPersonFindByLastName() {
        Person person = personService.getByLastName("sjsja") ;

        System.out.println(person);

    }
}

上一篇：解析URI与URL之间的区别与联系_基础知识

下一篇：略谈对付SSH端口扫描，还有WP的MC支持

Spring Data JPA 2. HelloWorld

Spring Data JPA HelloWorld

使用 Spring Data JPA 进行持久层开发需要的四个步骤：

搭建环境

HelloWorld

序列化表单为json对象,datagrid带额外参提交一次查询后台用Spring data JPA 实现带条件的分页查询多表关联查询

spring data jpa碰到的坑

使用Spring Data JPA进行数据分页与排序

spring-data-jpa实现增删改查以及分页操作方法

详解Spring Data JPA使用@Query注解（Using @Query）

Spring Data JPA使用Sort进行排序（Using Sort）

详解Spring Data JPA系列之投影（Projection）的用法

spring data jpa使用详解(推荐)

javaweb各种框架组合案例(六)：springboot+spring data jpa（hibernate）+restful

Spring-Data-JPA整合MySQL和配置的方法

Spring Data JPA 2. HelloWorld

Spring Data JPA HelloWorld

使用 Spring Data JPA 进行持久层开发需要的四个步骤：

搭建环境

HelloWorld

序列化表单为json对象,datagrid带额外参提交一次查询 后台用Spring data JPA 实现带条件的分页查询 多表关联查询

spring data jpa碰到的坑

使用Spring Data JPA进行数据分页与排序

spring-data-jpa实现增删改查以及分页操作方法

详解Spring Data JPA使用@Query注解（Using @Query）

Spring Data JPA使用Sort进行排序（Using Sort）

详解Spring Data JPA系列之投影（Projection）的用法

spring data jpa使用详解(推荐)

javaweb各种框架组合案例(六)：springboot+spring data jpa（hibernate）+restful

Spring-Data-JPA整合MySQL和配置的方法

序列化表单为json对象,datagrid带额外参提交一次查询后台用Spring data JPA 实现带条件的分页查询多表关联查询