java & mysql 基础(三个类)

package org.zxj.Message;

public class MessageBo implements java.io.Serializable{

private String title, content;

private java.sql.Date date;

public void setTitle(String title){

this.title = title;

}

public void setContent(String content){

this.content = content;

}

public String getTitle(){

return this.title;

}

public String getContent(){

return this.content;

}

public java.sql.Date getDate(){

return this.date;

}

public void setDate(java.sql.Date date){

this.date = date;

}

}

package org.zxj.Message;

import java.sql.*;

import java.util.*;

public class MessageBean{

private Connection con;

MessageBo msg;

public MessageBean(){

String CLASSFORNAME="com.mysql.jdbc.Driver";

String SERVANDDB = "jdbc:mysql://127.0.0.1:3306/demo1";

String  USER = "root";

String PWD = "pf";

try{

Class.forName(CLASSFORNAME);

con = DriverManager.getConnection(SERVANDDB,USER,PWD);

}catch(Exception e){

e.printStackTrace();

}

}

// 该方法用来想MessageBean 传输外部数据

public void setMessage(MessageBo msg){

this.msg = msg;

}

// 该方法被jsp调用，向数据库存储信息

public void addMessage() throws Exception{

try{

PreparedStatement stm = con.prepareStatement("insert into message(title,content,messagetime) values(?,?,?)");

stm.setString(1,msg.getTitle());

stm.setString(2,msg.getContent());

stm.setDate(3,new java.sql.Date(new java.util.Date().getTime()));

try{

stm.executeUpdate();

}catch(Exception e){

}

}catch(Exception e){

}

}

//被jsp页面调用，用于获取数据

public Collection getMessage() throws Exception{

Collection ret = new ArrayList();

try{

Statement stm = con.createStatement();

ResultSet result = stm.executeQuery("select count(*) from message");

int message_count = 0 ;

if (result.next()){

message_count = result.getInt(1);

result.close();

}

if(message_count > 0){

result = stm.executeQuery("select title,content,messageTime from message order by time desc");

while(result.next()){

String title = result.getString("title");

String content = result.getString("content");

java.sql.Date date = result.getDate("messageTime");

MessageBo messagebo = new MessageBo();

messagebo.setTitle(title);

messagebo.setContent(content);

messagebo.setDate(date);

ret.add(messagebo);

}

}

con.close();

}catch(Exception e){

}

return ret;

}

}

package org.zxj.Message;

import org.zxj.Message.MessageBean;

import org.zxj.Message.MessageBo;

public class test{

public static void main(String[] args) throws Exception{

MessageBo messagebo = new MessageBo();

messagebo.setTitle("abc");

messagebo.setContent("aaaaa");

messagebo.setDate(new java.sql.Date(new java.util.Date().getTime()));

MessageBean mb = new MessageBean();

mb.setMessage(messagebo);

mb.addMessage();

System.out.println("Nice");

}

}