第十二章 Spring4 支持参数命名的JdbcTemplate

NamedParameterJdbcTemplate 的使用；支持命名参数变量； org.springframework.jdbc.core.namedparam.NamedParameterJdbcTemplate


一、xml配置：

<?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">
     
    <!-- 配置数据源 -->
	<bean id="dataSource" class="org.apache.commons.dbcp.BasicDataSource" destroy-method="close">
        <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>
    
    <!-- 参数读取文件 -->
	<context:property-placeholder location="jdbc.properties"/>
    
    <!-- 支持命名参数变量的JdbcTemplate，StudentDaoImpl中的参数使用变量名，相比原来的问好更加清晰 -->
    <bean id="namedParameterJdbcTemplate" class="org.springframework.jdbc.core.namedparam.NamedParameterJdbcTemplate">
    	<constructor-arg ref="dataSource"></constructor-arg>
    </bean>
	
	<!-- 数据库操作类 -->
	<bean id="studentDao" class="com.fx.dao.impl.StudentDaoImpl">
		<property name="namedParameterJdbcTemplate" ref="namedParameterJdbcTemplate"></property>
	</bean> 
	
	<!-- 业务操作类 -->
	<bean id="studentService" class="com.fx.service.impl.StudentServiceImpl">
		<property name="studentDao" ref="studentDao"></property>
	</bean> 
	
</beans>

二、java代码：

package com.fx.dao.impl;

import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.List;

import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.jdbc.core.RowCallbackHandler;
import org.springframework.jdbc.core.namedparam.MapSqlParameterSource;
import org.springframework.jdbc.core.namedparam.NamedParameterJdbcTemplate;

import com.fx.dao.StudentDao;
import com.fx.model.Student;

public class StudentDaoImpl implements StudentDao{

	private NamedParameterJdbcTemplate namedParameterJdbcTemplate;
	
	public void setNamedParameterJdbcTemplate(
			NamedParameterJdbcTemplate namedParameterJdbcTemplate) {
		this.namedParameterJdbcTemplate = namedParameterJdbcTemplate;
	}

	@Override
	public int addStudent(Student student) {
		// 命名参数变量
		String sql="insert into t_student values(null,:name,:age)";
		MapSqlParameterSource sps=new MapSqlParameterSource();
		sps.addValue("name", student.getName());
		sps.addValue("age", student.getAge());
		return namedParameterJdbcTemplate.update(sql,sps);
	}

	@Override
	public int updateStudent(Student student) {
		// 命名参数变量
		String sql="update t_student set name=:name,age=:age where id=:id";
		MapSqlParameterSource sps=new MapSqlParameterSource();
		sps.addValue("name", student.getName());
		sps.addValue("age", student.getAge());
		sps.addValue("id", student.getId());
		return namedParameterJdbcTemplate.update(sql,sps);
	}

	@Override
	public int deleteStudent(int id) {
		// 命名参数变量
		String sql="delete from t_student where id=:id";
		MapSqlParameterSource sps=new MapSqlParameterSource();
		sps.addValue("id", id);
		return namedParameterJdbcTemplate.update(sql,sps);
	}

	@Override
	public List<Student> findStudents() {
		String sql="select * from t_student";
		final List<Student> studentList=new ArrayList<Student>();
		namedParameterJdbcTemplate.query(sql, new RowCallbackHandler(){

			@Override
			public void processRow(ResultSet rs) throws SQLException {
				Student student=new Student();
				student.setId(rs.getInt("id"));
				student.setName(rs.getString("name"));
				student.setAge(rs.getInt("age"));
				studentList.add(student);
			}
			
		});
		return studentList;
	}

}