• JavaWeb学习:Spring的JDBC的模板


    一、JDBC模板使用入门

      ①、创建项目,引入jar包

      • 引入基本开发包
        • spring-beans-5.2.9.RELEASE.jar
        • spring-context-5.2.9.RELEASE.jar
        • spring-core-5.2.9.RELEASE.jar
        • spring-expression-5.2.9.RELEASE.jar
        • com.springsource.org.apache.commons.logging-1.1.1.jar
      • 数据库驱动
        • sqljdbc42.jar
      • Spring的JDBC模板的jar包
        • spring-jdbc-5.2.9.RELEASE.jar
        • spring-tx-5.2.9.RELEASE.jar

        

      ②、创建数据库和表

    create database [HibernateDB]
    USE [HibernateDB]
    CREATE TABLE [dbo].[account](
        [id] [int] IDENTITY(1,1) NOT NULL,
        [name] [varchar](50) NULL,
        [money] [decimal](18, 2) NULL,
     CONSTRAINT [PK_account] PRIMARY KEY CLUSTERED 
    (
        [id] ASC
    )WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, 
    ALLOW_PAGE_LOCKS = ON) ON [PRIMARY] ) ON [PRIMARY] GO

      ③、使用JDBC的模板:保存数据

    public class JdbcDemo {
        @Test
        public void demo1() {
        //创建连接池
        DriverManagerDataSource dataSource=new DriverManagerDataSource();
        dataSource.setDriverClassName("com.microsoft.sqlserver.jdbc.SQLServerDriver");
        dataSource.setUrl("jdbc:sqlserver://localhost:1433;databaseName=HibernateDB;");
        dataSource.setUsername("sa");
        dataSource.setPassword("AAA@111");
        
        //创建jdbc模板
        JdbcTemplate jdbcTemplate=new JdbcTemplate(dataSource);
        jdbcTemplate.update("insert into account values(?,?)","zhangsan",1000000.00);
        }
    }

      ④、将连接池和JDBC模板交给Spring管理

        Ⅰ、引入spring-aop-5.x.jar

        Ⅱ、新建Spring的配置文件

    <beans xmlns="http://www.springframework.org/schema/beans"
        xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
        xsi:schemaLocation="
            http://www.springframework.org/schema/beans 
         https://www.springframework.org/schema/beans/spring-beans.xsd"
    > <bean id="dataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource"> <property name="driverClassName" value="com.microsoft.sqlserver.jdbc.SQLServerDriver"/> <property name="url" value="jdbc:sqlserver://localhost:1433;databaseName=HibernateDB;"/> <property name="username" value="sa"/> <property name="password" value="AAA@111"/> </bean> <bean id="jdbcTemplate" class="org.springframework.jdbc.core.JdbcTemplate"> <!-- 属性注入 jdbcTemplate实例化时,需要dataSource--> <property name="dataSource" ref="dataSource"></property> </bean> </beans>

        Ⅲ、测试方法

    //使用@SpringJUnitConfig此注解需要引入spring-test...jar包
    @SpringJUnitConfig(locations = "classpath:applicationContext.xml")
    public class JdbcDemo {
        @Autowired
        private JdbcTemplate jdbcTemplate;
        @Test
        public void demo1() {
        
        jdbcTemplate.update("insert into account values(?,?)","zhangsan",1000000.00);
        }
    }

    二、使用开源的数据库连接池

      ①、DBCP的使用

        Ⅰ、引入jar包

          com.springsource.org.apache.commons.dbcp-1.2.2.osgi.jar

          com.springsource.org.apache.commons.logging-1.1.1.jar

        Ⅱ、配置DBCP连接池

        <bean id="dataSource" class="org.apache.commons.dbcp.BasicDataSource">
            <property name="driverClassName" value="com.microsoft.sqlserver.jdbc.SQLServerDriver"/>
            <property name="url" value="jdbc:sqlserver://localhost:1433;databaseName=HibernateDB;"/>
            <property name="username" value="sa"/>
            <property name="password" value="AAA@111"/>
        </bean>
        
        <bean id="jdbcTemplate" class="org.springframework.jdbc.core.JdbcTemplate">
            <!-- 属性注入  jdbcTemplate实例化时,需要dataSource-->
            <property name="dataSource" ref="dataSource"></property>
        </bean>

      ②、C3P0的使用

        Ⅰ、引入c3p0连接池jar包

          com.springsource.com.mchange.v2.c3p0-0.9.1.2.jar

        Ⅱ、配置c3p0连接池

        <bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource">
            <property name="driverClass" value="com.microsoft.sqlserver.jdbc.SQLServerDriver"/>
            <property name="jdbcUrl" value="jdbc:sqlserver://localhost:1433;databaseName=HibernateDB;"/>
            <property name="user" value="sa"/>
            <property name="password" value="AAA@111"/>
        </bean>
        
        <bean id="jdbcTemplate" class="org.springframework.jdbc.core.JdbcTemplate">
            <!-- 属性注入  jdbcTemplate实例化时,需要dataSource-->
            <property name="dataSource" ref="dataSource"></property>
        </bean>

    三、抽取配置到属性文件(.properties)

      ①、定义一个属性文件(jdbc.properties)

    jdbc.driverClass=com.microsoft.sqlserver.jdbc.SQLServerDriver
    jdbc.url=jdbc:sqlserver://localhost:1433;databaseName=HibernateDB;
    jdbc.username=sa
    jdbc.password=AAA@111

      ②、在Spring的配置文件中引入属性文件

        Ⅰ、通过一个bean标签引入(很少)

        <bean class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer">
            <property name="location" value="classpath:jdbc.properties"/>
        </bean>

        Ⅱ、通过context标签引入

    <context:property-placeholder location="classpath:jdbc.properties"/>

      ③、引入属性文件的值

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

    四、使用JDBC的模板完成CRUD的操作

      ①、插入

    @SpringJUnitConfig(locations = "classpath:applicationContext.xml")
    public class JdbcDemo {
    
        @Autowired
        private JdbcTemplate jdbcTemplate;
    
        @Test
        public void demo1() {
        jdbcTemplate.update("insert into account values(?,?)", "zhangsan", 1000000.00);
        }
    }

      ②、更新

        @Test
        public void demo2() {
        jdbcTemplate.update("update account set name=?,money=? where id =?", "lisi", 2000000.00, 2);
        }

      ③、删除

        @Test
        public void demo3() {
        jdbcTemplate.update("delete from account where id=?", 3);
        }

    以上[.update()]方法就可以了

      ④、查询

        Ⅰ、查询某个属性(单个值)

        @Test
        public void demo4() {
        String name = jdbcTemplate.queryForObject("select name from account where id=?", String.class, 4);
        System.out.println(name);
        }
    
        @Test
        public void demo5() {
        Long count = jdbcTemplate.queryForObject("select count(*) from account ", Long.class);
        System.out.println(count);
        }

        Ⅱ、查询某个属性集合

        @Test
        public void demo8() {
        List<Integer> list = jdbcTemplate.queryForList("select id from account ",Integer.class);
        for (Integer id : list) {
            System.out.println(id);
        }
        }

    注意queryForList(sql,elementType)中的elementType:不支持自定义bean,这个class也只是支持Integer,String这些基本类型

        Ⅲ、查询返回对象或集合

        @Test
        public void demo6() {
        Account account = jdbcTemplate.queryForObject("select * from account where id=?", new MyRowMapper(), 4);
        System.out.println(account);
        }
    
        @Test
        public void demo7() {
        List<Account> list = jdbcTemplate.query("select * from account ",new MyRowMapper());
        for (Account account : list) {
            System.out.println(account);
        }
        }
    
        class MyRowMapper implements RowMapper<Account> {
          @Override
          public Account mapRow(ResultSet rs, int rowNum) throws SQLException {
              Account account = new Account();
              account.setId(rs.getInt("id"));
              account.setName(rs.getString("name"));
              account.setMoney(rs.getBigDecimal("money"));
              return account;
          }
        }
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  • 原文地址:https://www.cnblogs.com/WarBlog/p/14133044.html
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