正在开发“模拟”聊天室项目，有意提高者进来参与吧！（无论高中低手都有帮助的）

Question

各位好象误会我的意思了，这个聊天室所有的功能都是用System.out.println("功能")来代替具体的细节，没有从真正意义上实现的！只是探讨基础知识！

Answer 1

代码如下：
import java.io.*;
import java.util.*;//commonmember.class
class CommonMember{
            String UserMessage;
            CommonMember(String UserMessage){
            this.UserMessage=UserMessage;
                                             }
public void ShowMessage(){
            System.out.println("you are "+UserMessage+"and you can:");
                           }
public void PublicChat(){
            System.out.println("publicchat()");
                         }
public void SendMessage(){
            System.out.println("sendmessage()");
                          }  
                    }
//firstmember.class
class FirstMember extends CommonMember{
           String UserMessage;
           FirstMember(String UserMessage){
           super(UserMessage);
           this.UserMessage=UserMessage;
                                           }
public void PrivateChat(){
           System.out.println("privatechat()"); 
                          }   
                   }
//secondmember.class
class SecondMember extends FirstMember{
          String UserMessage;
          SecondMember(String UserMessage){
          super(UserMessage);
          this.UserMessage=UserMessage;
                                           }
public void DeleteMessage(){
          System.out.println("deletemessage()");
                            }
                    }
//thirdmember.class                    
class ThirdMember extends SecondMember{
          String UserMessage;
          ThirdMember(String UserMessage){
          super(UserMessage);
          this.UserMessage=UserMessage;
                                           }  
public void IncreaseGrade(){
          System.out.println("increasegrade()");
                             }   
                 } 
//checkmember.class                   
class CheckMember{
          String UserName;
          String UserPassword;
          CheckMember(String UserName,String UserPassword){
          this.UserName=UserName;
          this.UserPassword=UserPassword;
                                                      }
public boolean CheckName(){
  
      return true;
                      }
public boolean CheckPassword(){
      
      return true;
                           }
              }
//chatroom.class
class ChatRoom{public static void prt(String s){
      System.out.println(s);
                            }
public static void main(String[] args) throws IOException{
      InputStreamReader reader=new InputStreamReader(System.in);
      BufferedReader input=new BufferedReader(reader);
      prt("Enter your name:");
      String name=input.readLine();
      prt("Enter your password:");
      String password=input.readLine();
     
      if(name=="Tom"&&password=="123"){这里有些错误，因为我还没学到io,所以请各位指教
      ThirdMember tm=new ThirdMember("thirdmember");
      tm.ShowMessage();
      tm.PublicChat();
      tm.SendMessage();
      tm.PrivateChat();
      tm.DeleteMessage();
      tm.IncreaseGrade();
                                           }
      else 
      prt("you muse be registered before you enter the chatroom");
                                     }
      }   

Answer 2

if(name=="Tom"&&password=="123"){这里有些错误，因为我还没学到io,所以请各位指教
      应改为if(name.equals("tom")&&password.equals("123"))