JdbcTemplate是最基本的Spring JDBC模板,这个模板支持简单的JDBC数据库访问功能以及基于索引参数的查询。
为了使 JDBC 更加易于使用,Spring 在 JDBCAPI 上定义了一个抽象层, 以此建立一个JDBC存取框架,Spring Boot Spring Data-JPA。
作为 SpringJDBC 框架的核心, JDBC 模板的设计目的是为不同类型的JDBC操作提供模板方法. 每个模板方法都能控制整个过程,并允许覆盖过程中的特定任务。
通过这种方式,可以在尽可能保留灵活性的情况下,将数据库存取的工作量降到最低。
Spring JDBC由4个部分组成,即core、datasource、object、support。
(1)core包:提供JDBC模板类,其中JdbcTemplate是core包的核心类。
(2)datesource包:提供简化访问JDBC数据源工具类,并提供一些DataSource简单实现类,从而使这些DataSource获取的连接能自动得到Spring事务管理的支持。
(3)object包:提供关系数据的对象表示形式,如MappingSqlQuery、SqlUpdate、SqlCall、SqlFunction等。
(4)support包:提供将JDBC异常转换为DAO非检查异常的转化类和一些工具类。
JdbcTemplate主要提供以下五类方法:
execute方法:可以用于执行任何SQL语句,一般用于执行DDL语句;
update方法及batchUpdate方法:update方法用于执行新增、修改、删除等语句;batchUpdate方法用于执行批处理相关语句;
query方法及queryForXXX方法:用于执行查询相关语句;
call方法:用于执行存储过程、函数相关语句。
JdbcTemplate实例(配置)
实体类:
package com.te.entity; public class Accounts { private int accountid; private String accountname; private double balance; public int getAccountid() { return accountid; } public void setAccountid(int accountid) { this.accountid = accountid; } public String getAccountname() { return accountname; } public void setAccountname(String accountname) { this.accountname = accountname; } public double getBalance() { return balance; } public void setBalance(double balance) { this.balance = balance; } }
Dao接口层:
public interface AccountDao { //查询全部 List<Accounts> getAll(); }
Dao接口实现层:
public class AccountDaoImpl extends JdbcDaoSupport implements AccountDao { @Override public List<Accounts> getAll() { //RowMapper接口或抽象类 /* List<Accounts> query = this.getJdbcTemplate().query("select * from accounts", new RowMapper<Accounts>() { public Accounts mapRow(ResultSet var1, int var2) throws SQLException { Accounts accounts=new Accounts(); accounts.setAccountname(var1.getString("accountname")); accounts.setAccountid(var1.getInt("accountid")); accounts.setBalance(var1.getDouble("balance")); return accounts; } });*/ List<Accounts> query = this.getJdbcTemplate().query("select * from accounts", new BeanPropertyRowMapper<>(Accounts.class)); return query; } }
Service业务接口层:
public interface AccountService { //查询全部 List<Accounts> getAll(); }
ServiceImpl业务实现层:
public class AccountServiceImpl implements AccountService { private AccountDao accountDao; public void setAccountDao(AccountDao accountDao) { this.accountDao = accountDao; } @Override public List<Accounts> getAll() { return accountDao.getAll(); } }
jdbc.properties
driver=com.mysql.jdbc.Driver url=jdbc:mysql:///account user=root password=123
applicationContext.xml文件
<?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:tx="http://www.springframework.org/schema/tx" 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/tx http://www.springframework.org/schema/tx/spring-tx.xsd http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop.xsd"> <!--添加jdbc--> <bean class="org.springframework.context.support.PropertySourcesPlaceholderConfigurer"> <property name="location" value="classpath:jdbc.properties"></property> </bean> <!--配置数据源--> <bean id="dataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource"> <property name="url" value="${url}"></property> <property name="driverClassName" value="${driver}"></property> <property name="username" value="${user}"></property> <property name="password" value="${password}"></property> </bean> <!--配置jdbcTemplate核心对象--> <bean id="jdbcTemplate" class="org.springframework.jdbc.core.JdbcTemplate"> <property name="dataSource" ref="dataSource"></property> </bean> <!--Dao接口的实现类对象--> <bean id="accountDao" class="com.te.daoimpl.AccountDaoImpl"> <property name="jdbcTemplate" ref="jdbcTemplate"></property> </bean> <!--service接口的实现类对象--> <bean id="accountService" class="com.te.serviceImpl.AccountServiceImpl"> <property name="accountDao" ref="accountDao"></property> </bean> <!--配置事务管理器--> <bean id="transactionManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager"> <property name="dataSource" ref="dataSource"></property> </bean> <!--配置事务--> <tx:advice id="txAdvice" transaction-manager="transactionManager"> <tx:attributes> <tx:method name="getAll" propagation="REQUIRED" isolation="READ_COMMITTED" /> </tx:attributes> </tx:advice> <!--定义切面--> <aop:config> <aop:advisor advice-ref="txAdvice" pointcut="execution(* com.te.service.*.*(..))"></aop:advisor> </aop:config> </beans>
测试:
public class AccountTest { /*jdbcTemplate+Spring的整合*/ @Test public void test01(){ ApplicationContext ctx=new ClassPathXmlApplicationContext("applicationContext.xml"); AccountService accountService = ctx.getBean("accountService",AccountService.class); for (Accounts accounts:accountService.getAll()){ System.out.println("用户:"+accounts.getAccountname()+"====="+accounts.getBalance()); } }
}
结果:
JdbcTemplate实例(注解)
entity实体类:
package com.te.entity; public class Accounts { private int accountid; private String accountname; private double balance; public int getAccountid() { return accountid; } public void setAccountid(int accountid) { this.accountid = accountid; } public String getAccountname() { return accountname; } public void setAccountname(String accountname) { this.accountname = accountname; } public double getBalance() { return balance; } public void setBalance(double balance) { this.balance = balance; } }
Dao接口层:
public interface AccountDao { //查询全部 List<Accounts> getAll(); }
DaoImpl实现层:
@Repository("accountDao") public class AccountDaoImpl implements AccountDao { @Resource private JdbcTemplate jdbcTemplate; @Override public List<Accounts> getAll() { //RowMapper接口或抽象类 /* List<Accounts> query = this.getJdbcTemplate().query("select * from accounts", new RowMapper<Accounts>() { public Accounts mapRow(ResultSet var1, int var2) throws SQLException { Accounts accounts=new Accounts(); accounts.setAccountname(var1.getString("accountname")); accounts.setAccountid(var1.getInt("accountid")); accounts.setBalance(var1.getDouble("balance")); return accounts; } });*/ List<Accounts> query = this.jdbcTemplate.query("select * from accounts", new BeanPropertyRowMapper<>(Accounts.class)); return query; } }
Service业务层:
public interface AccountService { //查询全部 List<Accounts> getAll(); }
ServiceImpl业务实现层:
@Service("accountService") public class AccountServiceImpl implements AccountService { @Resource(name = "accountDao") private AccountDao accountDao; @Override public List<Accounts> getAll() { return accountDao.getAll(); } }
applicationContext.xml文件:
<?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"
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">
<!--扫描注解-->
<context:component-scan base-package="com.zhu"></context:component-scan>
<!--添加jdbc-->
<bean class="org.springframework.context.support.PropertySourcesPlaceholderConfigurer">
<property name="location" value="classpath:jdbc.properties"></property>
</bean>
<!--配置数据源-->
<bean id="dataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource">
<property name="url" value="${url}"></property>
<property name="driverClassName" value="${driver}"></property>
<property name="username" value="${user}"></property>
<property name="password" value="${password}"></property>
</bean>
<!--配置jdbcTemplate核心对象-->
<bean id="jdbcTemplate" class="org.springframework.jdbc.core.JdbcTemplate">
<property name="dataSource" ref="dataSource"></property>
</bean>
</beans>
测试:
public class ZhuTeset { @Test public void test01(){ ApplicationContext ctx=new ClassPathXmlApplicationContext("application-zhu.xml"); AccountService accountServiceImpl = (AccountService) ctx.getBean("accountService"); List<Accounts> all = accountServiceImpl.getAll(); for (Accounts accounts:all){ System.out.println(accounts.getAccountname()); } } }
结果: