一、SpringData簡介

Spring Data: Spring 的一個子項(xiàng)目捂掰。用于簡化數(shù)據(jù)庫訪問碘梢，支持NoSQL和關(guān)系數(shù)據(jù)庫存儲。其主要目標(biāo)是使數(shù)據(jù)庫的訪問變得方便快捷儡陨。
官網(wǎng)：https://spring.io/projects/spring-data#learn

Spring Data 項(xiàng)目所支持NoSQL存儲：
- - MongoDB（文檔數(shù)據(jù)庫）
- - Neo4j （圖形數(shù)據(jù)庫）
- - Redis（鍵/值存儲）
- - Hbase（列族數(shù)據(jù)庫）
Spring Data 項(xiàng)目所支持的關(guān)系數(shù)據(jù)存儲技術(shù)：
- - JDBC
- - JPA
JPA Spring Data: 致力于減少數(shù)據(jù)訪問層（DAO）的開發(fā)量。開發(fā)者唯一要做的量淌，就只是聲明持久層的接口骗村，其他都交給Spring Data JPA 來幫你完成！

二呀枢、Maven依賴

<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>
    <spring.version>5.1.8.RELEASE</spring.version>
    <hibernate.version>5.4.3.Final</hibernate.version>
</properties>

<dependencies>
    <!--sping依賴-->
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-core</artifactId>
        <version>${spring.version}</version>
    </dependency>
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-context</artifactId>
        <version>${spring.version}</version>
    </dependency>
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-context-support</artifactId>
        <version>${spring.version}</version>
    </dependency>
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-orm</artifactId>
        <version>${spring.version}</version>
    </dependency>
    <!--SpringData-JPA-->
    <dependency>
        <groupId>org.springframework.data</groupId>
        <artifactId>spring-data-jpa</artifactId>
        <version>2.1.9.RELEASE</version>
    </dependency>
    <!--hibernate-->
    <dependency>
        <groupId>org.hibernate</groupId>
        <artifactId>hibernate-core</artifactId>
        <version>${hibernate.version}</version>
    </dependency>
    <dependency>
        <groupId>org.hibernate</groupId>
        <artifactId>hibernate-entitymanager</artifactId>
        <version>${hibernate.version}</version>
    </dependency>
    <!--lombok-->
    <dependency>
        <groupId>org.projectlombok</groupId>
        <artifactId>lombok</artifactId>
        <version>1.18.8</version>
        <scope>provided</scope>
    </dependency>
    <!--log4j-->
    <dependency>
        <groupId>log4j</groupId>
        <artifactId>log4j</artifactId>
        <version>1.2.17</version>
    </dependency>
    <dependency>
        <groupId>org.slf4j</groupId>
        <artifactId>slf4j-log4j12</artifactId>
        <version>1.7.26</version>
        <scope>test</scope>
    </dependency>
    <!--數(shù)據(jù)庫連接池-->
    <dependency>
        <groupId>com.alibaba</groupId>
        <artifactId>druid</artifactId>
        <version>1.1.19</version>
    </dependency>
    <!-- mysql配置 -->
    <dependency>
        <groupId>mysql</groupId>
        <artifactId>mysql-connector-java</artifactId>
        <version>5.1.44</version>
    </dependency>
    <!--spring測試-->
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-test</artifactId>
        <version>${spring.version}</version>
        <scope>test</scope>
    </dependency>
    <!--單元測試-->
    <dependency>
        <groupId>junit</groupId>
        <artifactId>junit</artifactId>
        <version>4.12</version>
        <scope>test</scope>
    </dependency>
</dependencies>

三胚股、Spring配置

在Spring的配置文件里添加即可。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: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 https://www.springframework.org/schema/context/spring-context.xsd http://www.springframework.org/schema/data/jpa http://www.springframework.org/schema/data/jpa/spring-jpa.xsd">

    <!-- 打開Spring的Annotation支持 -->
    <context:annotation-config />
    <!--數(shù)據(jù)源配置-->
    <bean id="dataSource" class="com.alibaba.druid.pool.DruidDataSource" init-method="init" destroy-method="close">
        <property name="driverClassName">
            <value>com.mysql.jdbc.Driver</value>
        </property>
        <property name="url">
            <value>jdbc:mysql://127.0.0.1:3306/spring_data?useUnicode=true&amp;characterEncoding=UTF-8&amp;useSSL=false&amp;autoReconnect=true&amp;failOverReadOnly=false&amp;serverTimezone=GMT%2b8</value>
        </property>
        <property name="username">
            <value>root</value>
        </property>
        <property name="password">
            <value>1234</value>
        </property>
        <!-- 配置初始化大小硫狞、最小、最大 -->
        <property name="initialSize" value="1"/>
        <property name="minIdle" value="1"/>
        <property name="maxActive" value="10"/>
        <!-- 配置獲取連接等待超時的時間 -->
        <property name="maxWait" value="10000"/>
        <!-- 配置間隔多久才進(jìn)行一次檢測晃痴，檢測需要關(guān)閉的空閑連接残吩，單位是毫秒 -->
        <property name="timeBetweenEvictionRunsMillis" value="60000"/>
        <!-- 配置一個連接在池中最小生存的時間，單位是毫秒 -->
        <property name="minEvictableIdleTimeMillis" value="300000"/>
        <property name="testWhileIdle" value="true"/>
        <!-- 這里建議配置為TRUE倘核，防止取到的連接不可用 -->
        <property name="testOnBorrow" value="true"/>
        <property name="testOnReturn" value="false"/>
        <!-- 打開PSCache泣侮，并且指定每個連接上PSCache的大小 -->
        <property name="poolPreparedStatements" value="true"/>
        <property name="maxPoolPreparedStatementPerConnectionSize" value="20"/>
        <!-- 這里配置提交方式，默認(rèn)就是TRUE紧唱，可以不用配置 -->
        <property name="defaultAutoCommit" value="true"/>
        <!-- 驗(yàn)證連接有效與否的SQL活尊，不同的數(shù)據(jù)配置不同 -->
        <property name="validationQuery" value="select 1 "/>
        <property name="filters" value="stat"/>
    </bean>
    <!--實(shí)體管理工廠-->
    <bean id="entityManagerFactory" class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean">
        <!--數(shù)據(jù)源-->
        <property name="dataSource" ref="dataSource" />
        <property name="packagesToScan" value="com.neuedu.entity" />
        <property name="jpaVendorAdapter">
            <bean class="org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter">
                <!--般情況下，會在項(xiàng)目啟動的過程中漏益，自動檢查注解的實(shí)體和數(shù)據(jù)表蛹锰，
                如果數(shù)據(jù)庫不存在的表或者字段，會根據(jù)實(shí)體自動生成绰疤。-->
                <property name="generateDdl" value="true" />
                <property name="database" value="MYSQL" />
                <property name="databasePlatform" value="org.hibernate.dialect.MySQL5Dialect" />
                <property name="showSql" value="true" />
            </bean>
        </property>
        <property name="jpaDialect">
            <bean class="org.springframework.orm.jpa.vendor.HibernateJpaDialect" />
        </property>
        <property name="jpaPropertyMap">
            <map>
                <entry key="hibernate.query.substitutions" value="true 1, false 0" />
                <entry key="hibernate.default_batch_fetch_size" value="16" />
                <entry key="hibernate.max_fetch_depth" value="2" />
                <entry key="hibernate.generate_statistics" value="true" />
                <entry key="hibernate.bytecode.use_reflection_optimizer" value="true" />
                <entry key="hibernate.cache.use_second_level_cache" value="false" />
                <entry key="hibernate.cache.use_query_cache" value="false" />
            </map>
        </property>
    </bean>
    <!--事務(wù)管理器配置 -->
    <bean id="transactionManager" class="org.springframework.orm.jpa.JpaTransactionManager">
        <property name="entityManagerFactory" ref="entityManagerFactory" />
    </bean>
    <!-- JPA -->
    <jpa:repositories base-package="com.neuedu.repository"
                      entity-manager-factory-ref="entityManagerFactory"
                      transaction-manager-ref="transactionManager"/>

</beans>

LocalContainerEntityManagerFactoryBean：適用于所有環(huán)境的FactoryBean铜犬，能全面控制EntityManagerFactory配置,如指定Spring定義的DataSource等等。
dataSource：用于指定Spring定義的數(shù)據(jù)源轻庆；
jpaDialect：用于指定一些高級特性癣猾，如事務(wù)管理，獲取具有事務(wù)功能的連接對象等余爆，目前Spring提供HibernateJpaDialect纷宇、OpenJpaDialect 、EclipseLinkJpaDialect蛾方、TopLinkJpaDialect像捶、和DefaultJpaDialect實(shí)現(xiàn)上陕，注意DefaultJpaDialect不提供任何功能，因此在使用特定實(shí)現(xiàn)廠商JPA實(shí)現(xiàn)時需要指定JpaDialect實(shí)現(xiàn)作岖，如使用Hibernate就使用HibernateJpaDialect唆垃。當(dāng)指定jpaVendorAdapter屬性時可以不指定jpaDialect，會自動設(shè)置相應(yīng)的JpaDialect實(shí)現(xiàn)痘儡；
jpaPropertyMap：指定JPA屬性辕万；如Hibernate中指定是否顯示SQL的“hibernate.show_sql”屬性；

四沉删、Log4j配置 log4j.properties

log4j.rootLogger=all, stdout, file

log4j.appender.stdout=org.apache.log4j.ConsoleAppender
log4j.appender.stdout.Target=System.out
log4j.appender.stdout.layout=org.apache.log4j.PatternLayout
log4j.appender.stdout.layout.ConversionPattern=%d{yyyy-MM-dd HH:mm:ss} %-5p %c{1}:%L - %m%n

log4j.appender.file=org.apache.log4j.RollingFileAppender
log4j.appender.file.File=D:/logs/spring-data.log
log4j.appender.file.MaxFileSize=5KB
log4j.appender.file.MaxBackupIndex=10
log4j.appender.file.layout=org.apache.log4j.PatternLayout
log4j.appender.file.layout.ConversionPattern=%d{yyyy-MM-dd HH:mm:ss.S} %-5p %c{1}:%L - %m%n

五渐尿、實(shí)體類

@Entity
@Table(name = "admin")
@Data
public class Admin {
    @Id
    @GeneratedValue
    private Integer id;
    private String name;
}

六、JPA

@Repository
public interface  AdminRepository extends JpaRepository<Admin, Long> {
}

七矾瑰、單元測試

// 使用junit4進(jìn)行測試
@RunWith(SpringJUnit4ClassRunner.class)
// 加載配置文件
@ContextConfiguration({"classpath:applicationContext.xml" })
public class AdminRepositoryTest {
    @Autowired
    private AdminRepository adminRepository;
    @Test
    public void test(){
        Admin admin=new Admin();
        admin.setId(1);
        admin.setName("SpringData");
        adminRepository.save(admin);
    }
}

測試結(jié)果：

測試結(jié)果

執(zhí)行結(jié)果

八砖茸、常見問題