1.JDBC模板

• Spring是EE開發的一站式的框架，有EE開發的每層的解決方案。
• Spring對持久層也提供瞭解決方案：ORM模組和JDBC的模板。
• Spring提供了很多的模板用於簡化開發,如JDBC、Springmvc

2.JDBC模板入門

• 建立資料庫和表

create table account(
	id int primary key auto_increment,
	name varchar(20),
	money double
);

• 使用JDBC的模板

public class SpringJdbcTest
 
 {
    @Test
    public void test(){
        //1.建立資料庫連線池
        DriverManagerDataSource source = new DriverManagerDataSource();
        source.setDriverClassName("com.mysql.jdbc.Driver");
        source.setUrl("jdbc:mysql:///spring");
        source.setUsername("root");
        source.setPassword("123"
 
);
        //2.建立JDBC模板
        JdbcTemplate jdbcTemplate = new JdbcTemplate(source);
        jdbcTemplate.update("insert into account value(null,?,?)","zs",1000d);
    }
}

• 資料插入成功，顯示多了一條記錄！

3.Spring管理JDBC

• 配置檔案：

<?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:aop="http://www.springframework.org/schema/aop"
       xsi:schemaLocation="http://www.springframework.org/schema/beans
        http://www.springframework.org/schema/beans/spring-beans.xsd
        http://www.springframework.org/schema/aop
        http://www.springframework.org/schema/aop/spring-aop.xsd">
    <!--資料庫連線池配置-->
    <bean id="source" class="org.springframework.jdbc.datasource.DriverManagerDataSource">
        <property name="driverClassName" value="com.mysql.jdbc.Driver"/>
        <property name="url" value="jdbc:mysql:///spring"/>
        <property name="username" value="root"/>
        <property name="password" value="123"/>
    </bean>
    <bean id="jdbcTemplate" class="org.springframework.jdbc.core.JdbcTemplate">
    	<!--name是setDataSource的注入,是new JdbcTemplate(source)的注入的變形,類似setUrl-->
        <property name="dataSource" ref="source"/>
    </bean>
</beans>

• 測試類：

@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration("classpath:applicationContext.xml")
public class SpringJdbcTest2 {
    @Resource(name = "jdbcTemplate")
    private JdbcTemplate jdbcTemplate;

    @Test
    public void test() {
        jdbcTemplate.update("insert into account value(null,?,?)", "ls", 10000d);
    }
}

4.使用第三方連線池（只需要更改配置檔案就行）

• DBCP連線池

<?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:aop="http://www.springframework.org/schema/aop"
       xsi:schemaLocation="http://www.springframework.org/schema/beans
        http://www.springframework.org/schema/beans/spring-beans.xsd
        http://www.springframework.org/schema/aop
        http://www.springframework.org/schema/aop/spring-aop.xsd">    
    <!--配置dbcp連線池-->
    <bean id="dbcp" class="org.apache.commons.dbcp.BasicDataSource">
        <property name="driverClassName" value="com.mysql.jdbc.Driver"/>
        <property name="url" value="jdbc:mysql:///spring"/>
        <property name="username" value="root"/>
        <property name="password" value="123"/>
    </bean>
    <bean id="jdbcTemplate" class="org.springframework.jdbc.core.JdbcTemplate">
        <property name="dataSource" ref="dbcp"/>
    </bean>
</beans>

• C3P0

<?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:aop="http://www.springframework.org/schema/aop"
       xsi:schemaLocation="http://www.springframework.org/schema/beans
        http://www.springframework.org/schema/beans/spring-beans.xsd
        http://www.springframework.org/schema/aop
        http://www.springframework.org/schema/aop/spring-aop.xsd">   
    <!--配置c3p0連線池-->
    <bean id="c3p0" class="com.mchange.v2.c3p0.ComboPooledDataSource">
        <property name="driverClass" value="com.mysql.jdbc.Driver"/>
        <property name="jdbcUrl" value="jdbc:mysql:///spring"/>
        <property name="user" value="root"/>
        <property name="password" value="123"/>
    </bean>
    <bean id="jdbcTemplate" class="org.springframework.jdbc.core.JdbcTemplate">
        <property name="dataSource" ref="c3p0"/>
    </bean>

</beans>

• Druid

<?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:aop="http://www.springframework.org/schema/aop"
       xsi:schemaLocation="http://www.springframework.org/schema/beans
        http://www.springframework.org/schema/beans/spring-beans.xsd
        http://www.springframework.org/schema/aop
        http://www.springframework.org/schema/aop/spring-aop.xsd"> 
    <!--配置druid連線池-->
    <bean id="druid" class="com.alibaba.druid.pool.DruidDataSource">
        <property name="driverClassName" value="com.mysql.jdbc.Driver"/>
        <property name="url" value="jdbc:mysql:///spring"/>
        <property name="username" value="root"/>
        <property name="password" value="123"/>
    </bean>
    <bean id="jdbcTemplate" class="org.springframework.jdbc.core.JdbcTemplate">
        <property name="dataSource" ref="c3p0"/>
    </bean>
</beans>

5.載入屬性檔案（bean方式）

• src/下新建jdbc.propertied

driverClassName=com.mysql.jdbc.Driver
url=jdbc:mysql:///spring
username=root
password=123

• 配置檔案：

<?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:aop="http://www.springframework.org/schema/aop"
       xsi:schemaLocation="http://www.springframework.org/schema/beans
        http://www.springframework.org/schema/beans/spring-beans.xsd
        http://www.springframework.org/schema/aop
        http://www.springframework.org/schema/aop/spring-aop.xsd">
    <!--bean方式：載入屬性檔案-->
    <bean class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer">
        <property name="location" value="jdbc.properties"/>
    </bean>
    <!--配置druid連線池-->
    <bean id="druid" class="com.alibaba.druid.pool.DruidDataSource">
        <property name="driverClassName" value="${driverClassName}"/>
        <property name="url" value="${url}"/>
        <property name="username" value="${username}"/>
        <property name="password" value="${password}"/>
    </bean>
    <bean id="jdbcTemplate" class="org.springframework.jdbc.core.JdbcTemplate">
        <property name="dataSource" ref="druid"/>
    </bean>
</beans>

• 執行測試類即可！

6.載入屬性檔案（context方式）

• src/下新建jdbc.propertied

driverClassName=com.mysql.jdbc.Driver
url=jdbc:mysql:///spring
username=root
password=123

• 配置檔案：

<?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:aop="http://www.springframework.org/schema/aop"
       xmlns:context="http://www.springframework.org/schema/context"
       xsi:schemaLocation="http://www.springframework.org/schema/beans
        http://www.springframework.org/schema/beans/spring-beans.xsd
        http://www.springframework.org/schema/aop
        http://www.springframework.org/schema/aop/spring-aop.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd">
    <!--context方式：載入屬性檔案-->
    <context:property-placeholder location="classpath:jdbc.properties"/>
    <!--配置druid連線池-->
    <bean id="druid" class="com.alibaba.druid.pool.DruidDataSource">
        <!--key值不能和name一樣,加字首jdbc-->
        <property name="driverClassName" value="${jdbc.driverClassName}"/>
        <property name="url" value="${jdbc.url}"/>
        <property name="username" value="${jdbc.username}"/>
        <property name="password" value="${jdbc.password}"/>
    </bean>
    <bean id="jdbcTemplate" class="org.springframework.jdbc.core.JdbcTemplate">
        <property name="dataSource" ref="druid"/>
    </bean>
</beans>

7.JDBC模板的CRUD操作

• 插入操作

• 刪除操作

• 更新操作

• 查詢單個欄位值（以下忽略連線資料庫細節）

@Test
public void test() {
    /*查詢單個欄位name*/
    String name = jdbcTemplate.queryForObject("select name from account where id=?", String.class, 1);
    System.out.println(name);
}

• 查詢一條記錄

1. 新建domain類

import lombok.Getter;
import lombok.Setter;

@Getter@Setter
public class Account {
    private Integer id;
    private String name;
    private Double money;
    
    @Override
    public String toString() {
        return "Account{" +
                "id=" + id +
                ", name='" + name + '\'' +
                ", money=" + money +
                '}';
    }
}

2. 新建結果集處理器類

public class MyRowMap implements RowMapper<Account> {
    @Override
    public Account mapRow(ResultSet resultSet, int i) throws SQLException {
        Account account = new Account();
        account.setId(resultSet.getInt("id"));
        account.setName(resultSet.getString("name"));
        account.setMoney(resultSet.getDouble("money"));
        return account;
    }
}

3. 執行測試類

@Test
public void test() {
    Account account = jdbcTemplate.queryForObject("select * from account where id=?", new MyRowMap(), 1);
    System.out.println(account); //Account{id=1, name='zs', money=1000.0}
}

• 查詢所有記錄

4. domain類、結果集處理類不變
5. 測試類

@Test
public void test() {
    List<Account> query = jdbcTemplate.query("select * from account", new MyRowMap());
    for(Account account:query){
        System.out.println(account);
    }
}
//將迭代輸出每一個數據記錄的資訊