UserLogOn.java 文件代码如下:
package com.jb.logon;
import java.sql.*;
public class UserLogOn {
private String username;
private String userpassword;
private ResultSet rs;
private DB db=new DB();
public UserLogOn(){}
public void setUsername(String username){
this.username=username;
}
public String getUsername(){
return this.username;
}
public void setUserpassword(String userpassword){
this.userpassword=userpassword;
}
public String getUserpassword(){
return this.userpassword;
}
public String checkuser(){
String backstr="";
boolean =true;
if(this.username==null||this.username.equals("")){
backstr+="<li>请输入<b>用户名!</b></li><br>";
=false;
}
if(this.userpassword==null||this.userpassword.equals("")){
backstr+="<li>请输入<b>密 码!</b></li><br>";
=false;
}
if(){
String sql="select * from tb_logon where user_name='"+this.username+"' and user_password='"+this.userpassword+"'";
try{
rs=db.getRs(sql);
if(!rs.next())
backstr="登录失败!<br>输入的<b>用户名</b>或<b>密码</b>不存在!";
else
backstr="登录成功!<br><table><tr><td>用户名:</td><td>"+this.username+"</td></tr><tr><td>密 码:</td><td>"+this.userpassword+"</td></tr></table>";
}catch(Exception e){e.printStackTrace();}
}
db.closed();
return backstr;
}
}--------------------
编译的时候出现这样的出错提示:
UserLogOn.java:8:cannot resolve symbol
symbol:class DB
location:class com.jb.logon.UserLogOn
private DB db=new DB();我是不是没有引用 DB这个类呢?
望各位替小的指点下!
package com.jb.logon;
import java.sql.*;
public class UserLogOn {
private String username;
private String userpassword;
private ResultSet rs;
private DB db=new DB();
public UserLogOn(){}
public void setUsername(String username){
this.username=username;
}
public String getUsername(){
return this.username;
}
public void setUserpassword(String userpassword){
this.userpassword=userpassword;
}
public String getUserpassword(){
return this.userpassword;
}
public String checkuser(){
String backstr="";
boolean =true;
if(this.username==null||this.username.equals("")){
backstr+="<li>请输入<b>用户名!</b></li><br>";
=false;
}
if(this.userpassword==null||this.userpassword.equals("")){
backstr+="<li>请输入<b>密 码!</b></li><br>";
=false;
}
if(){
String sql="select * from tb_logon where user_name='"+this.username+"' and user_password='"+this.userpassword+"'";
try{
rs=db.getRs(sql);
if(!rs.next())
backstr="登录失败!<br>输入的<b>用户名</b>或<b>密码</b>不存在!";
else
backstr="登录成功!<br><table><tr><td>用户名:</td><td>"+this.username+"</td></tr><tr><td>密 码:</td><td>"+this.userpassword+"</td></tr></table>";
}catch(Exception e){e.printStackTrace();}
}
db.closed();
return backstr;
}
}--------------------
编译的时候出现这样的出错提示:
UserLogOn.java:8:cannot resolve symbol
symbol:class DB
location:class com.jb.logon.UserLogOn
private DB db=new DB();我是不是没有引用 DB这个类呢?
望各位替小的指点下!
解决方案 »
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