使用Spring JDBC框架连接并操作数据库

在前一篇博文JAVA通过JDBC连接并操作MySQL数据库中，我们知道如何通过JDBC连接并操作数据库，但是请看程序，整个程序连接数据库和关闭数据库占了很大一部分代码量，而且每次我们执行一下数据库操作都得来这么一大段重复代码，这是很烦人的。而在Spring框架中同样提供了JDBC框架，以供我们操作数据库。spring中的JDBC框架则可以为我们省去连接和关闭数据库的代码，我们只要关注我们想对数据库进行的操作即可，下面开始介绍吧。

同样的，我们需要在MySQL中创建一个table，以供我们测试使用。

CREATE TABLE student(
	ID VARCHAR(5),
	name VARCHAR(20),
	age int(3),
	FM VARCHAR(1),
	PRIMARY KEY(ID)
)

表格效果如下图：

有了数据库之后，建好maven工程，然后需要配置数据源。在Spring的JDBC框架中，数据源配置在Beans.xml中，当然这个文件名可以随便取的。

整个Beans.xml配置文件如下所示：

在这里有一点要注意characterEncoding前面的 & 需要更换成 & ，否则会报错。

接下来我们为数据库student创建一个类student.java

package SNOW.SpringJDBCtest;

public class Student{
	private String ID;
	private String name;
	private int age;
	private String FM;
	
	public Student(){		
	}
	
	public Student(String ID,String name,int age, String FM){
		this.ID = ID;
		this.name = name;
		this.age = age;
		this.FM = FM;
	}
	
	public void setID(String ID){
		this.ID = ID;
	}
	
	public String getID(){
		return this.ID;
	}

	public void setname(String name){
		this.name = name;
	}
	
	public String getname(){
		return this.name;
	}

	public void setage(int age){
		this.age = age;
	}
	
	public int getage(){
		return age;
	}
	
	public void setFM(String FM){
		this.FM = FM;
	}
	
	public String getFM(){
		return this.FM;
	}	
	
	public void display(){
		System.out.println(ID + " " + name + " " + age + " " + FM);
	}
	
	
}

有了Student类之后，还需要一个将SQL数据与student对象映射的类StudentMapper.java

package SNOW.SpringJDBCtest;

import java.sql.ResultSet;
import java.sql.SQLException;
import org.springframework.jdbc.core.RowMapper;

public class StudentMapper implements RowMapper {

	public Student mapRow(ResultSet rs, int rownum) throws SQLException {
		Student student = new Student();
		student.setID(rs.getString("ID"));
		student.setname(rs.getString("name"));
		student.setage(rs.getInt("age"));
		student.setFM(rs.getString("FM"));
		
		return student;		
	}
	
}

Spring JDBC框架是通过DAO（Data Access Object）来实现对数据库的读写数据操作的，并且在实现过程中应该由应用程序implements interface 来完成数据库的读写操作。

我们的接口定义如下：

package SNOW.SpringJDBCtest;

import java.util.List;
import javax.sql.DataSource;


public interface StudentDao{

	/** 
	 * This is the method to be used to initialize
	 * database resources ie. connection.
	 */	
	public void setdatasource(DataSource ds);	
	
	public void addstudent(Student student);
	
	public void delstudentbyID(String ID);
	
	public void delstudentbyname(String name);
	
	public void delallstudent();
	
	public void updstudent(Student student);
	
	public List allstudent();
	
	public List querystudentbyID(String ID);
	
	public List querystudentbyname(String name);
	
	public List querystudentbyage(int age);
	
	
}

接口实现定义如下：

package SNOW.SpringJDBCtest;

import java.util.List;

import javax.sql.DataSource;

import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.jdbc.core.RowCallbackHandler;


public class StudentDaoImp implements StudentDao{

	private DataSource datasource;
	private JdbcTemplate jdbcTemplateObject;
	
	
	public void setdatasource(DataSource ds) {
		this.datasource = ds;
		this.jdbcTemplateObject = new JdbcTemplate(datasource);		
	}

	public void addstudent(Student student) {
		String sql = "INSERT INTO class.student(ID,name,age,FM)VALUES(?,?,?,?)";
		
		jdbcTemplateObject.update(sql, student.getID(),
				student.getname(),student.getage(),student.getFM());
		return ;
	}

	public void delstudentbyID(String ID) {
		String sql = "DELETE FROM class.student WHERE ID=?";
		jdbcTemplateObject.update(sql,ID);
		return ;
	}

	public void delstudentbyname(String name) {
		String sql = "DELETE FROM class.student WHERE name=?";
		jdbcTemplateObject.update(sql,name);
		return ;		
	}

	public void delallstudent() {
		String sql = "DELETE FROM class.student";
		jdbcTemplateObject.update(sql);
		return ;	
	}

	public void updstudent(Student student) {
		String sql = "UPDATE class.student set name=?,age=?,FM=? WHERE ID=?";
		jdbcTemplateObject.update(sql,student.getname(),
				student.getage(),student.getFM(),student.getID());
		return ;
	}

	public List allstudent() {
		List students = null;
		String sql = "SELECT * FROM class.student";
		students = jdbcTemplateObject.query(sql, new StudentMapper());
		return students;
	}

	public List querystudentbyID(String ID) {
		List students = null;
		String sql = "SELECT * FROM class.student WHERE ID=?";
		students = jdbcTemplateObject.query(sql, new Object[]{ID}, new StudentMapper());
		return students;
	}

	public List querystudentbyname(String name) {
		List students = null;
		String sql = "SELECT * FROM class.student WHERE name=?";
		students = jdbcTemplateObject.query(sql, new Object[]{name}, new StudentMapper());
		return students;
	}

	public List querystudentbyage(int age) {
		List students = null;
		String sql = "SELECT * FROM class.student WHERE age=?";
		students = jdbcTemplateObject.query(sql, new Object[]{age}, new StudentMapper());
		return students;
	}
	
	public void displayall(){
		List students = allstudent();
		for(Student s : students){
			s.display();
		}
	}
	
	
}

实现了StudentDaoImp类之后需要装备到Beans.xml中，具体见最上面的Beans.xml代码。

写完以上代码就写完了主要的功能操作了，接下来我们写个测试程序Maintest.java

package SNOW.SpringJDBCtest;

import java.util.List;

import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

public class Maintest{
	public static void main(String [] args){
		ApplicationContext context = 
				new ClassPathXmlApplicationContext("SNOW/SpringJDBCtest/Beans.xml");
		StudentDaoImp studentDaoImp = (StudentDaoImp)context.getBean("studentDaoImp");
		
		
		String[] ID = { "2008", "2009", "2010", "1990", "2015","2018" };
		String[] name = { "Wang", "Hui", "Yu", "Yuan", "Yuan", "Yang"};
		int[] age = { 16, 18, 20, 20, 22, 21 };
		String[] FM = {"F", "F", "M", "M", "M", "F"};		
		Student student = null;
		List students = null;
		
		System.out.println("---------addstudent-------------");
		for(int i=0; i

因为创建的Maven项目，其中pom.xml如下：

  4.0.0

  SNOW
  SpringJDBCtest
  0.0.1-SNAPSHOT
  jar

  SpringJDBCtest
  http://maven.apache.org

    	
    UTF-8
  

    	
    
      	junit
      	junit
      	3.8.1
      	test
    
    
 	
		mysql
		mysql-connector-java
		5.1.35
	

    
        org.springframework
        spring-context
        4.1.6.RELEASE
    

	
		org.springframework
		spring-jdbc
		4.1.6.RELEASE
	
	
	
		org.springframework
		spring-tx  
		4.1.6.RELEASE
	    
	
  

最终运行结果如下：

五月 29, 2015 8:51:29 下午 org.springframework.context.support.ClassPathXmlApplicationContext prepareRefresh
信息: Refreshing org.springframework.context.support.ClassPathXmlApplicationContext@384e57ba: startup date [Fri May 29 20:51:29 CST 2015]; root of context hierarchy
五月 29, 2015 8:51:30 下午 org.springframework.beans.factory.xml.XmlBeanDefinitionReader loadBeanDefinitions
信息: Loading XML bean definitions from class path resource [SNOW/SpringJDBCtest/Beans.xml]
五月 29, 2015 8:51:31 下午 org.springframework.jdbc.datasource.DriverManagerDataSource setDriverClassName
信息: Loaded JDBC driver: com.mysql.jdbc.Driver
---------addstudent-------------
1990 Yuan 20 M
2008 Wang 16 F
2009 Hui 18 F
2010 Yu 20 M
2015 Yuan 22 M
2018 Yang 21 F
---------updatestudent-------------
1990 Yuan 18 M
2008 Wang 16 F
2009 Hui 18 F
2010 Yu 20 M
2015 Yuan 22 M
2018 Yang 21 F
---------querystudentbyID-------------
1990 Yuan 18 M
---------querystudentbyname-------------
1990 Yuan 18 M
2015 Yuan 22 M
---------querystudentbyage-------------
2010 Yu 20 M
---------delstudentbyage-------------
1990 Yuan 18 M
2008 Wang 16 F
2009 Hui 18 F
2010 Yu 20 M
2015 Yuan 22 M
---------delstudentbyname-------------
1990 Yuan 18 M
2008 Wang 16 F
2010 Yu 20 M
2015 Yuan 22 M
---------delallstudent-------------

本文参考文献：    

http://www.tutorialspoint.com/spring/spring_jdbc_framework.htm

http://www.tutorialspoint.com/spring/spring_jdbc_example.htm