Spring学习笔记----JdbcTemplet和NamedParameterJdbcTemplate的使用

JdbcTemplet是Spring下一个很好用的jdbc小工具，而且使用起来也是很简单

需求：实现基本的数据库操作

贴上代码：

dataSource.properties

jdbc.user = rootjdbc.password =123456jdbc.driverClass = com.mysql.jdbc.Driverjdbc.jdbcUrl = jdbc:mysql:///spring1jdbc.initPoolSize=5jdbc.maxPoolSize=10

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"       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">    <!--导入资源文件-->    <context:property-placeholder location="classpath:dataSource.properties"></context:property-placeholder>    <!--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JdbcTemplate-->    <bean id="jdbcTemplate" class="org.springframework.jdbc.core.JdbcTemplate">        <property name="dataSource" ref="dataSource"></property>    </bean></beans>

Student.java

package cn.limbo.spring.jdbc;/** * Created by Limbo on 16/7/14. */public class Student {    private int id;    private String studentName;    private String email;    private int deptId;    public int getId() {        return id;    }    public void setId(int id) {        this.id = id;    }    public String getStudentName() {        return studentName;    }    public void setStudentName(String studentName) {        this.studentName = studentName;    }    public String getEmail() {        return email;    }    public void setEmail(String email) {        this.email = email;    }    public int getDeptId() {        return deptId;    }    public void setDeptId(int deptId) {        this.deptId = deptId;    }    @Override    public String toString() {        return "Student{" +                "id=" + id +                ", studentName='" + studentName + '\'' +                ", email='" + email + '\'' +                ", deptId=" + deptId +                '}';    }}

Department.java

package cn.limbo.spring.jdbc;/** * Created by Limbo on 16/7/14. */public class Department {    private int id;    private String name;    public int getId() {        return id;    }    public void setId(int 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 + '\'' +                '}';    }}

JDBCTest.java

package cn.limbo.spring.jdbc;import org.springframework.context.ApplicationContext;import org.springframework.context.support.ClassPathXmlApplicationContext;import org.springframework.jdbc.core.BeanPropertyRowMapper;import org.springframework.jdbc.core.JdbcTemplate;import org.springframework.jdbc.core.RowMapper;import org.springframework.jdbc.core.namedparam.BeanPropertySqlParameterSource;import org.springframework.jdbc.core.namedparam.NamedParameterJdbcTemplate;import org.springframework.jdbc.core.namedparam.SqlParameterSource;import javax.sql.DataSource;import java.sql.SQLException;import java.util.ArrayList;import java.util.HashMap;import java.util.List;import java.util.Map;/** * Created by Limbo on 16/7/14. */public class JDBCTest {    private static ApplicationContext ctx = new ClassPathXmlApplicationContext("applicationContext.xml");    private static JdbcTemplate jdbcTemplate = (JdbcTemplate) ctx.getBean("jdbcTemplate");    private static NamedParameterJdbcTemplate namedParameterJdbcTemplate = ctx.getBean(NamedParameterJdbcTemplate.class);    public void testDataSource() throws SQLException {        DataSource dataSource = ctx.getBean(DataSource.class);        System.out.println(dataSource.getConnection());    }    /**     * 执行UPDATE,INSERT,DELETE     */    public static void testUpdate()    {        String sql = "UPDATE student SET student_name = ? WHERE id = ?";        jdbcTemplate.update(sql,"Kylin",2);    }    /**     * 批量INSERT,UPDATE,DELETE     * 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,那么多条就需要多个     */    public static void BatchUpdate()    {        String sql = "INSERT INTO student(id,student_name,email,Dept_No)VALUES(?,?,?,?)";        List<Object[]> batchArgs = new ArrayList<>();        batchArgs.add(new Object[]{4,"AA","[e-mail]",1});        batchArgs.add(new Object[]{5,"BB","[e-mail]",2});        batchArgs.add(new Object[]{6,"CC","[e-mail]",1});        batchArgs.add(new Object[]{7,"DD","[e-mail]",2});        batchArgs.add(new Object[]{8,"EE","[e-mail]",1});        jdbcTemplate.batchUpdate(sql,batchArgs);    }    /**     * 从数据库中获取一条记录,实际得到一个对象     * 注意不是调用这个方法queryForObject(java.lang.String sql,java.lang.Class<T> requiredType,java.lang.Object... args)     * 需要调用中这个方法: queryForObject(java.lang.String sql,@NotNull org.springframework.jdbc.core.RowMapper<T> rowMapper,java.lang.Object... args)     * 1.其中的RowMapper指定如何去映射结果集的行,常用的实现类为BeanPropertyRowMapper<>(Student.class);     * 2.使用SQL中的列的别名完成列名和类的属性名的映射     * 3.不支持级联属性     */    public static void testQueryForObject()    {        String sql = "SELECT id,student_name,email,Dept_No FROM student WHERE id = ?";        RowMapper<Student> rowMapper = new BeanPropertyRowMapper<>(Student.class);        Student student = jdbcTemplate.queryForObject(sql,rowMapper,1);        System.out.println(student);    }    /**     * 查到实体类的集合     * 注意不是调用queryForList     */    public static void testQueryForList()    {        String sql = "SELECT id, student_name,email,Dept_No FROM student WHERE id > ?";        RowMapper<Student> rowMapper = new BeanPropertyRowMapper<>(Student.class);        List<Student> list = jdbcTemplate.query(sql,rowMapper,1);        System.out.println(list);    }    /**     * 获取单个列的值,或者做统计查询     */    public static void testQueryForObject2()    {        String sql = "SELECT count(id) FROM student";        int count = jdbcTemplate.queryForObject(sql,Integer.class);        System.out.println(count);    }    /**     * 可以为参数取名字,参数多了更加便于维护     * 1.好处:若有多个参数,则不用再去对应位置,直接对应参数名,便于维护     * 2.缺点:较为麻烦     */    public static void testNamedParameterJdbcTemplate()    {        String sql = "INSERT INTO student(id,student_name,email,Dept_No) VALUES(:id,:name,:email,:deptid)";        Map<String , Object> paramMap = new HashMap<>();        paramMap.put("id",9);        paramMap.put("name","Limbo");        paramMap.put("email","[e-mail]");        paramMap.put("deptid",1);        namedParameterJdbcTemplate.update(sql,paramMap);    }    /**     * 使用具名参数的时候,可以用update(java.lang.String sql,org.springframework.jdbc.core.namedparam.SqlParameterSource paramSource)进行更新操作     * 直接将一个对象作为参数     * 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     */    public static void testNamedParameterJdbcTemplate2()    {        String sql = "INSERT INTO student(id,student_name,email,Dept_No) VALUES(:id,:studentName,:email,:deptId)";        Student student = new Student();        student.setStudentName("wyh");        student.setId(10);        student.setEmail("[e-mail]");        student.setDeptId(1);        SqlParameterSource paramSource = new BeanPropertySqlParameterSource(student);        namedParameterJdbcTemplate.update(sql,paramSource);    }    public static void main(String[] args) {        testNamedParameterJdbcTemplate2();    }}

以上就是用JdbcTemplet和NamedParameterJdbcTemplate实现的增删改查，当然需要取出一个实体的时候可以这样写

StudentDao.java

package cn.limbo.spring.jdbc;import org.springframework.beans.factory.annotation.Autowired;import org.springframework.jdbc.core.BeanPropertyRowMapper;import org.springframework.jdbc.core.JdbcTemplate;import org.springframework.jdbc.core.RowMapper;import org.springframework.stereotype.Repository;/** * Created by Limbo on 16/7/15. */@Repositorypublic class StudentDao{    @Autowired    private JdbcTemplate jdbcTemplate;    public Student get(int id)    {        String sql = "SELECT * FROM student WHERE id = ?";        RowMapper<Student> rowMapper = new BeanPropertyRowMapper<>(Student.class);        Student student = jdbcTemplate.queryForObject(sql,rowMapper,1);        return student;    }}