使用JdbcTemplate
导入必要的maven依赖
<!-- https://mvnrepository.com/artifact/org.springframework/spring-context -->
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-context</artifactId>
<version>4.1.2.RELEASE</version>
</dependency>
<!-- https://mvnrepository.com/artifact/org.springframework/spring-core -->
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-core</artifactId>
<version>4.1.3.RELEASE</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-beans</artifactId>
<version>4.1.3.RELEASE</version>
</dependency>
<!-- https://mvnrepository.com/artifact/org.springframework/spring-aop -->
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-aop</artifactId>
<version>4.1.3.RELEASE</version>
</dependency>
<!-- https://mvnrepository.com/artifact/org.springframework/spring-aspects -->
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-aspects</artifactId>
<version>4.1.3.RELEASE</version>
</dependency>
<!-- https://mvnrepository.com/artifact/org.springframework/spring-jdbc -->
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-jdbc</artifactId>
<version>4.1.3.RELEASE</version>
</dependency>
<!-- https://mvnrepository.com/artifact/org.aspectj/aspectjweaver -->
<dependency>
<groupId>org.aspectj</groupId>
<artifactId>aspectjweaver</artifactId>
<version>1.6.8</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/mysql/mysql-connector-java -->
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>5.1.21</version>
</dependency>
<!-- https://mvnrepository.com/artifact/junit/junit -->
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>4.12</version>
<scope>test</scope>
</dependency>
简单配置连接mysql的数据库配置文件db.properties
jdbc.user=root
jdbc.password=zwf1233
jdbc.driverClass=com.mysql.jdbc.Driver
jdbc.jdbcUrl=jdbc:mysql://localhost:3306/springstudy3
jdbc.initPoolSize=5
jdbc.maxPoolSize=10
创建applicationContext.xml配置文件，添加包扫描，导入db配置文件并配置c3p0数据源，最后添加Spring的JdbcTemplete。
<?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-4.1.xsd">
<context:component-scan base-package="com.fafa.spring.*"></context:component-scan>
<!-- 导入资源文件 -->
<context:property-placeholder location="classpath:db.properties"/>
<!-- 配置c3p0数据源 -->
<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="jdbcUrl" value="${jdbc.jdbcUrl}"></property>
<property name="driverClass" value="${jdbc.driverClass}"></property>
<property name="initialPoolSize" value="${jdbc.initPoolSize}"></property>
<property name="maxPoolSize" value="${jdbc.maxPoolSize}"></property>
</bean>
<!-- 配置Spring的JdbcTemplete -->
<bean id="jdbcTemplete" class="org.springframework.jdbc.core.JdbcTemplate">
<property name="dataSource" ref="dataSource"></property>
</bean>
</beans>
创建mysql数据库中的相关表及数据：
/*Table structure for table `departments` */
DROP TABLE IF EXISTS `departments`;
CREATE TABLE `departments` (
`ID` tinyint(10) NOT NULL AUTO_INCREMENT,
`DEPT_NAME` varchar(20) DEFAULT NULL,
PRIMARY KEY (`ID`)
) ENGINE=InnoDB AUTO_INCREMENT=4 DEFAULT CHARSET=utf8;
/*Data for the table `departments` */
insert into `departments`(`ID`,`DEPT_NAME`) values (1,'财务部'),(2,'开发部'),(3,'公关部');
/*Table structure for table `employees` */
DROP TABLE IF EXISTS `employees`;
CREATE TABLE `employees` (
`ID` tinyint(10) NOT NULL AUTO_INCREMENT,
`LAST_NAME` varchar(20) DEFAULT NULL,
`EMAIL` varchar(50) DEFAULT NULL,
`DEPT_ID` tinyint(10) DEFAULT NULL,
PRIMARY KEY (`ID`)
) ENGINE=InnoDB AUTO_INCREMENT=6 DEFAULT CHARSET=utf8;
/*Data for the table `employees` */
insert into `employees`(`ID`,`LAST_NAME`,`EMAIL`,`DEPT_ID`) values (1,'Tom','tom@163.com',1),(2,'Jerry','hery@163.com',2),(3,'Mike','mike@sohu.com',3),(4,'Rose','rose@sina.com',3),(5,'fafa','fafa@qq.com',2);
创建JDBCTest类：
public class JDBCTest {
private ApplicationContext ctx = null;
private JdbcTemplate jdbcTemplate;
{
ctx = new ClassPathXmlApplicationContext("classpath:applicationContext.xml");
jdbcTemplate = (JdbcTemplate) ctx.getBean("jdbcTemplete");
}
@Test
public void testDataSource() throws SQLException {
DataSource dataSource = (DataSource) ctx.getBean("dataSource");
System.out.println(dataSource.getConnection());
}
}
测试结果：
com.mchange.v2.c3p0.impl.NewProxyConnection@1113fd74 [wrapping: com.mysql.jdbc.JDBC4Connection@3764d36e]
使用jdbcTemplete更新数据：
/**
* 执行insert,update,delete
*/
@Test
public void testUpdate() {
String sql = "UPDATE employees SET last_name=? where id=?";
jdbcTemplate.update(sql, "Jack", 5);
}
测试结果（前后结果对比）：
执行批量更新
/**
* 执行批量更新:批量insert，update，delete
* 后面最后一个参数是Object[]的list类型：因为修改一条记录需要一个Object数组，多条就需要多个Object数组
*/
@Test
public void testBatchUpdate(){
String sql = "INSERT INTO employees(last_name,email,dept_id) VALUES(?,?,?)";
List<Object[]> batchArgs = new ArrayList<>();
batchArgs.add(new Object[]{"AA","aa@fafa.com",1});
batchArgs.add(new Object[]{"BB","bb@fafa.com",2});
batchArgs.add(new Object[]{"CC","cc@fafa.com",3});
batchArgs.add(new Object[]{"DD","dd@fafa.com",3});
batchArgs.add(new Object[]{"EE","ee@fafa.com",2});
jdbcTemplate.batchUpdate(sql, batchArgs);
}
执行结果：
查询结果为对象：
新建Employee类
public class Employee {
private Integer id;
private String lastName;
private String email;
private Integer deptId;
public Integer getId() {
return id;
}
public void setId(Integer id) {
this.id = id;
}
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;
}
public Integer getDeptId() {
return deptId;
}
public void setDeptId(Integer deptId) {
this.deptId = deptId;
}
@Override
public String toString() {
return "Employee [id=" + id + ", lastName=" + lastName + ", email="
+ email + ", deptId=" + deptId + "]";
}
}
测试方法：
/**
* 从数据库中获取一条记录，实际得到一个对应的对象
*
注意不是调用queryForObject(String sql, Class<Employee> requiredType, Object... args) 这个方法
* 而需要调用queryForObject(String sql, RowMapper<Employee> rowMapper, Object... args)
* 1. 其中rowMapper指定如何去映射结果集的行，常用的实现类为BeanPropertyRowMapper
* 2. 使用SQL中的别名完成列名和属性名的映射，列入last_name lastName
* 3. 不支持级联属性，JdbcTemplete 到底是一个JDBC的小工具而不是ORM框架
*/
@Test
public void testQueryForObject() {
String sql = "SELECT id, last_name, email, dept_id as \"department.id\" FROM employees WHERE id=?";
RowMapper<Employee> rowMapper = new BeanPropertyRowMapper<>(Employee.class);
Employee employee = jdbcTemplate.queryForObject(sql, rowMapper, 5);
System.out.println(employee);
}
查询结果：
Employee [id=5, lastName=Jack, email=fafa@qq.com, deptId=null]
查询实体类集合：
/**
* 查询实体类集合
* 注意调用的不是queryForList方法
*/
@Test
public void testQueryForList(){
String sql = "SELECT id, last_name, email FROM employees WHERE id>?";
RowMapper<Employee> rowMapper = new BeanPropertyRowMapper<>(Employee.class);
List<Employee> employee = jdbcTemplate.query(sql, rowMapper, 5);
System.out.println(employee);
}
测试结果：
Employee [id=6, lastName=AA, email=aa@fafa.com, deptId=null], Employee [id=7, lastName=BB, email=bb@fafa.com, deptId=null], Employee [id=8, lastName=CC, email=cc@fafa.com, deptId=null], Employee [id=9, lastName=DD, email=dd@fafa.com, deptId=null], Employee [id=10, lastName=EE, email=ee@fafa.com, deptId=null]]
获取单列值或作统计：
/**
* 获取单个列的值，或作统计查询
* 使用queryForObject(String sql, Class<Long> requiredType)
*/
@Test
public void testQueryForObject2(){
String sql = "SELECT count(id) FROM employees";
long count = jdbcTemplate.queryForObject(sql, Long.class);
System.out.println(count);
}
测试结果：10
使用Dao获取数据，新建EmployeeDao类：
@Repository
public class EmployeeDao {
@Autowired
private JdbcTemplate jdbcTemplate;
public Employee get(Integer id){
String sql = "SELECT id, last_name, email FROM employees WHERE id=?";
RowMapper<Employee> rowMapper = new BeanPropertyRowMapper<>(Employee.class);
Employee employee = jdbcTemplate.queryForObject(sql, rowMapper, 5);
return employee;
}
}
测试类：
public class JDBCTest {
private ApplicationContext ctx = null;
private EmployeeDao employeeDao;
{
ctx = new ClassPathXmlApplicationContext("classpath:applicationContext.xml");
employeeDao = ctx.getBean(EmployeeDao.class);
}
@Test
public void testEmployeeDao(){
System.out.println(employeeDao.get(1));
}
}
测试结果：
Employee [id=5, lastName=Jack, email=fafa@qq.com, deptId=null]
使用JdbcDaoSupport
新建Department类和DepartmentDao类
不推荐使用JdbcDaoSupport这种方式，而推荐直接使用JdbcTemplate作为DAO类成员变量
public class Department {
private Integer id;
private String name;
public Integer getId() {
return id;
}
public void setId(Integer id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
@Override
public String toString() {
return "Department [id=" + id + ", name=" + name + "]";
}
}
/**
* 不推荐使用JdbcDaoSupport这种方式，而推荐直接使用JdbcTemplate作为DAO类成员变量
* @author Stark
*
*/
@Repository
public class DepartmentDao extends JdbcDaoSupport {
@Autowired
public void setDataSource2(DataSource dataSource){
setDataSource(dataSource);
}
public Department get(Integer id) {
String sql = "SELECT id, dept_name name FROM departments WHERE id = ?";
RowMapper<Department> rowMapper = new BeanPropertyRowMapper<>(Department.class);
Department department = getJdbcTemplate().queryForObject(sql, rowMapper,1);
return department;
}
}
public class JDBCTest {
private ApplicationContext ctx = null;
private DepartmentDao departmentDao;
{
ctx = new ClassPathXmlApplicationContext("classpath:applicationContext.xml");
departmentDao = ctx.getBean(DepartmentDao.class);
}
@Test
public void testDepartmentDao() {
System.out.println(departmentDao.get(1));
}
}
测试结果：
Department [id=1, name=财务部]
使用 NamedParameterJdbcTemplate
在xml配置文件中增加NamedParameterJdbcTemplate：
<!-- 配置NamedParameterJdbcTemplate，该对象可以使用具名参数，其没有无参数的构造器，所以必须为其构造器指定参数 -->
<bean id="namedParameterJdbcTemplate" class="org.springframework.jdbc.core.namedparam.NamedParameterJdbcTemplate">
<constructor-arg ref="dataSource"/>
</bean>
测试类：
public class JDBCTest {
private ApplicationContext ctx = null;
private NamedParameterJdbcTemplate namedParameterJdbcTemplate;
{
ctx = new ClassPathXmlApplicationContext("classpath:applicationContext.xml");
namedParameterJdbcTemplate = ctx.getBean(NamedParameterJdbcTemplate.class);
}
/**
* 可以为参数起名称。
* 1. 好处：若有多个参数，则不用再去对应位置了，而直接对应参数名，增强了可维护性；
* 2. 缺点：较为麻烦。
*/
@Test
public void testNamedParameterJdbcTemplate() {
String sql = "INSERT INTO employees(last_name,email,dept_id)VALUES(:ln,:email,:deptid)";
Map<String, Object> paramMap = new HashMap<String, Object>();
paramMap.put("ln", "FF");
paramMap.put("email", "test@fafa.com");
paramMap.put("deptid", 2);
namedParameterJdbcTemplate.update(sql, paramMap);
}
/**
* 使用具名参数时，可以使用update(String sql, SqlParameterSource paramSource)方法进行更新操作
* 1. SQL语句中的参数名和类的属性一致！
* 2. 使用 SqlParameterSource 的 BeanPropertySqlParameterSource实现类作为参数
*/
@Test
public void testNamedParameterJdbcTemplate2(){
String sql = "INSERT INTO employees(last_name,email,dept_id) VALUES (:lastName,:email,:deptId)";
Employee employee = new Employee();
employee.setLastName("XYZ");
employee.setEmail("xyz@fafa.com");
employee.setDeptId(3);
SqlParameterSource paramSource = new BeanPropertySqlParameterSource(employee);
namedParameterJdbcTemplate.update(sql, paramSource);
}
}
测试结果：
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