java连接mysql数据库增删改查操作记录

//注意，这是连接mysql的方法

import java.sql.Connection;//java包
public class DBConnection
	{
	private String dbDriver="com.mysql.jdbc.Driver"; 
	private String dbUrl="jdbc:mysql://[ip地址]:[端口号]/[数据库名]";//根据实际情况变化
	private String dbUser="root";
	private String dbPass="root";
	public Connection getConn()
	{
	Connection conn=null;
	try
	{
	Class.forName(dbDriver);
	}
	catch (ClassNotFoundException e)
	{
	e.printStackTrace();
	}
	try
	{
	conn = DriverManager.getConnection(dbUrl,dbUser,dbPass);//注意是三个参数
	}
	catch (SQLException e)
	{
	e.printStackTrace();
	}
	return conn;
	}
	}

	public int insert()
	{
	int i=0;
	String sql="insert into (表名)(列名1,列明2) values(?,?)";
	Connection cnn=getConn();

	try{
	PreparedStatement preStmt =cnn.prepareStement(sql);
	preStmt.setString(1,值);
	preStmt.setString(2,值);//或者：preStmt.setInt(1,值);
	i=preStmt.executeUpdate();
	}
	catch (SQLException e)
	{
	e.printStackTrace();
	}
	return i;//返回影响的行数，1为执行成功
	}

	public int update
	{
	int i=0;
	String sql="update (表名) set (列名1)=?,列明2=? where (列名)=？";//注意要有where条件
	Connection cnn=getConn();


	try{
	PreparedStatement preStmt =cnn.prepareStatement(sql);
	preStmt.setString(1,(值));
	preStmt.setString(2,(值));//或者：preStmt.setInt(1,值);
	preStmt.setInt(3,(值));
	i=preStmt.executeUpdate();
	}
	catch (SQLException e)
	{
	e.printStackTrace();
	}
	return i;//返回影响的行数，1为执行成功
	}

public String select
	{
	String sql = "select * from (表名) where (列名)=(值)";
	Connection cnn = getConn();//此处为通过自己写的方法getConn()获得连接
	try
	{
	Statement stmt = conn.createStatement();
	ResultSet rs = stmt.executeQuery(sql);

	if(rs.next())
	{
	int m1 = rs.getInt(1);//或者为rs.getString(1)，根据数据库中列的值类型确定，参数为第一列
	String m2 = rs.getString(2);
	}
	//可以将查找到的值写入类，然后返回相应的对象
	}
	catch (SQLException e)
	{
	e.printStackTrace();
	}
	return (相应的值的变量);
	}

	public int delete()
	{
	String sql = "delete from (表名) where (列名)=(值)";
	int i=0;
	Connection conn = getConn();//此处为通过自己写的方法getConn()获得连接
	try
	{
	Statement stmt = conn.createStatement();
	i = stmt.executeUpdate(sql);
	}
	catch (SQLException e)
	{
	e.printStackTrace();
	}
	return i;//如果返回的是1，则执行成功;
	}