JDBC

Connection conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/test", "root", "root");
CallableStatement cs = conn.prepareCall("{call p_save_dept(?,?,?,?)}");
cs.setInt(1,12);
cs.setString(2,"dev");
cs.setString(3,"NJ");
cs.registerOutParameter(4, JDBCType.INTEGER);
cs.execute() ;
int out = cs.getInt(4);
System.out.println(out);
cs.close();
conn.close();

 //构造函数与增删改查方法的组合：
QueryRunner()
      update(Connection conn, String sql, Object... params)
      query(Connection conn, String sql, ResultSetHandler<T> rsh, Object... params)
 
QueryRunner(DataSource ds)     
      update(String sql, Object... params)
      query(String sql, ResultSetHandler<T> rsh, Object... params)

package com.test.dbcp;
import java.sql.Connection;
import java.util.Properties;
import javax.sql.DataSource;
import org.apache.commons.dbcp.BasicDataSourceFactory;
public class DbcpDataSource {
/*
 * 重点：创建一个DataSource
 * 步骤为：1、用Properties类读取配置文件。
 * 2、通过工厂类，读取这个Properties类获取的配置文件，创建出DataSource
 * DataSource作用：
 * 创建DataSource可以返回多个连接。可以实现dbutil简化操作数据库的流程。
 */
//1、创建一个静态的datasource
private static DataSource ds;
//2、在静态代码块中，给ds赋值
static{
	//读取资源文件
	try{
		Properties p = new Properties();
			p.load(DbcpDataSource.class.getClassLoader().getResourceAsStream("dbcp.properties"));
		//在dbcp中有一个工厂类，读取一个资源文件,创建一个datasource
			ds = BasicDataSourceFactory.createDataSource(p);
			System.out.println("创建DataSource为"+ds);
		}catch(Exception e){
		throw new RuntimeException(e);
		}
	}
//提供一个方法用于获取整个datasource对象
public static DataSource getDataSource(){
		return ds;
	}
//提供一个方法，获取connection连接
public static Connection getConnection(){
	Connection con = null;
	try{
			con = ds.getConnection();
			System.out.println("通过DataSource获取connection连接"+con);
		}catch(Exception e){
			e.printStackTrace();
		}
	return con;
	}
}

static {
    //模拟初始化数据
    Properties prop = new Properties();
    prop.setProperty("driverClassName","com.mysql.jdbc.Driver");
    prop.setProperty("url","jdbc:mysql://localhost:3306/customer?useSSL=false&characterEncoding=utf8");
    prop.setProperty("password","root");
    prop.setProperty("username","root");
    try{
        dataSource = DruidDataSourceFactory.createDataSource(prop);
    }catch (Exception e) {
        e.printStackTrace();
    }
    //初始化 连接池
}

package com.test.ts;
import java.sql.SQLException;
import java.util.List;
import javax.persistence.Version;
import org.apache.commons.dbutils.QueryRunner;
import org.apache.commons.dbutils.handlers.ArrayHandler;
import org.apache.commons.dbutils.handlers.ArrayListHandler;
import org.junit.Test;
import com.test.dbcp.DbcpDataSource;
public class DbutilTests {
/*
 * dbutil向数据库新增数据
 */
@Test
public void add() throws SQLException{
	//1、申明QueryRunner对象执行SQL语句
	QueryRunner run1 = new QueryRunner(DbcpDataSource.getDataSource()); //申明对象，获取DataSource链接池
	//2、书写SQL字符串语句
	String sq1 = "INSERT INTO student(id,namee,sex,birth,department,address)"
				+ "VALUES(3,'王思','男',1995,'英文系','山东沧州')";
	//3、执行sql语句
	int result1 = run1.update(sq1);
		System.out.println("新增数据库结果，更新了数据有："+result1+"条");
	}
/*
 * dbutil 修改数据库数据
 *
 */
@Test
public void update() throws SQLException{
	//1、申明QueryRunner对象执行SQL语句
	QueryRunner run2 = new QueryRunner(DbcpDataSource.getDataSource());//申明对象，获取DataSource连接池
	//2、书写SQL字符串语句
	String sq2 = "UPDATE student SET sex=? WHERE id=?";
	//3、执行SQL语句
	int result2 = run2.update(sq2, "男",16);
		System.out.println("更新数据库结果，更新了数据有："+result2+"条");
	}
/*
 * dbutil 删除数据库数据
 */
@Test
public void delete() throws SQLException{
	//1、申明QueryRunner对象执行SQL语句
	QueryRunner run3 = new QueryRunner(DbcpDataSource.getDataSource());//申明对象，获取DataSource连接池
	//2、书写SQL字符串语句（这个sql语句的作用是每次删除ID号最大的数据）
	String sq3 = "DELETE FROM student WHERE id IN "
				+ "(SELECT a.id FROM "
				+ "(SELECT MAX(id) id FROM student a WHERE id IN"
				+ "(SELECT id FROM student b WHERE a.id=b.id ORDER BY id DESC)) a)";
	//3、执行SQL语句
	int result3 = run3.update(sq3);
		System.out.println("更新数据库结果，更新了数据有："+result3+"条");
	}
/*
 * dbutil 查询，将结果封装成Object对象，返回第一行数据
 */
@Test
public void query() throws SQLException{
	//1、申明QueryRunner对象执行SQL语句
	QueryRunner run = new QueryRunner(DbcpDataSource.getDataSource());//申明对象，获取DataSource链接池
	//2、查询
	String sq4 = "Select * from student";
		Object[] var = run.query(sq4, new ArrayHandler());
	if(var !=null){
			System.out.print("输出学生表查询的信息"+"\n");
		for(Object o :var){
				System.out.print(o+"\n");
			}
		}
	}
/*
 * dbutil 查询 ，将结果封装成Object对象，返回所有的数据
 *
 */
@Test
public void query2() throws SQLException{
	//1、申明QueryRunner对象执行SQL语句
	QueryRunner run5 = new QueryRunner(DbcpDataSource.getDataSource());
	//2、书写sql语句
	String sq5 = "select * from student";
	//3、查询sql
		List<Object[]> list = run5.query(sq5, new ArrayListHandler());
	//4、遍历结果
	if(list!=null){
		for(Object[] os:list){
			for(Object o :os){
					System.out.println("ArrayListHandler()显示查询到的所有数据："+o+"\t");
				}
				System.out.println("\n--------------------------------------------");
			}
		}
	}
}