代码：
DButil.java(连接关闭数据库的类)
import java.sql.DriverManager;import java.sql.SQLException;import java.util.Properties;import com.mysql.jdbc.Connection;public class DButil {/** 打开数据库*/private static String driver;//连接数据库的驱动private static String url;private static String username;private static String password;static {driver="com.mysql.jdbc.Driver";//需要的数据库驱动url="jdbc:mysql://localhost:3306/test";//数据库名路径username="root";password="root";}public static Connection open(){try {Class.forName(driver);return (Connection) DriverManager.getConnection(url,username, password);} catch (Exception e) {System.out.println("数据库连接失败！");// TODO Auto-generated catch blocke.printStackTrace();}//加载驱动return null;}/** 关闭数据库*/public static void close(Connection conn){if(conn!=null){try {conn.close();} catch (SQLException e) {// TODO Auto-generated catch blocke.printStackTrace();}}}}
test.java(连接数据库成功后实现简单的查询功能)
import java.sql.DriverManager;import java.sql.ResultSet;import java.sql.SQLException;import com.mysql.jdbc.Connection;import com.mysql.jdbc.Statement;public class Test{public static void main(String[] args) {Connection conn=DButil.open();//连接数据库// try {//Class.forName("com.mysql.jdbc.Driver");//} catch (ClassNotFoundException e) {//e.printStackTrace();//}/** JDBC查询数据库*/String sql="select * from classa";try {Statement stmt=(Statement) conn.createStatement();ResultSet rs=stmt.executeQuery(sql);//结果集就是带指针的数组while(rs.next()){int num=rs.getInt(1);String name=rs.getString(2);String score=rs.getString(3);System.out.println(num+","+name+","+score);}} catch (SQLException e) {// TODO Auto-generated catch blocke.printStackTrace();}finally {DButil.close(conn);}}}
运行结果：
12301,Haige,8712302,Yangxu,9212303,Huahua,36
总结：整个操作需要导入一个名为“mysql-connector-java-5.1.6-bin”的Java连接MySQL数据库的jar包，才能驱动连接。
