考试前的练题--图书管理系统

bean层

public class anfo {//admin
    
    private String account;
    private String using;
    private String cold;
    
    public String getAccount() {
        return account;
    }
    public void setAccount(String account) {
        this.account = account;
    }
    public String getUsing() {
        return using;
    }
    public void setUsing(String using) {
        this.using = using;
    }
    public String getCold() {
        return cold;
    }
    public void setCold(String cold) {
        this.cold = cold;
    }
    
    
}

public class bookform {//book
private String code;
private String name;
private String master;
private String output;
private int maxamount;
private int amount;

public String getCode() {
return code;
}
public void setCode(String code) {
this.code = code;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getMaster() {
return master;
}
public void setMaster(String master) {
this.master = master;
}
public String getOutput() {
return output;
}
public void setOutput(String output) {
this.output = output;
}
public int getAmount() {
return amount;
}
public void setAmount(int amount) {
this.amount = amount;
}
public int getMaxamount() {
return maxamount;
}
public void setMaxamount(int maxamount) {
this.maxamount = maxamount;
}


}

package bean;

public class readerform {//reader
private String code;
private String name;
private String sex;
private String acd;

public String getCode() {
return code;
}
public void setCode(String code) {
this.code = code;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getSex() {
return sex;
}
public void setSex(String sex) {
this.sex = sex;
}
public String getAcd() {
return acd;
}
public void setAcd(String acd) {
this.acd = acd;
}


}

链接数据库

import java.beans.Statement;
import java.sql.*;

public class bd {
    private String going="com.mysql.cj.jdbc.Driver";
    private Connection connect;
    private Statement state;
    private String link="jdbc:mysql://localhost:3306/place?serverTimezone=UTC";
    private ResultSet rs;
    

    public String getGoing() {
        return going;
    }

    public void setGoing(String going) {
        this.going = going;
    }

    public Connection getConnect() {
        return connect;
    }

    public void setConnect(Connection connect) {
        this.connect = connect;
    }

    public Statement getState() {
        return state;
    }

    public void setState(Statement state) {
        this.state = state;
    }

    public String getLink() {
        return link;
    }

    public void setLink(String link) {
        this.link = link;
    }

    public ResultSet getRs() {
        return rs;
    }

    public void setRs(ResultSet rs) {
        this.rs = rs;
    }
    
    public Connection getlink() {
        try {
            Class.forName(going);
        } catch (ClassNotFoundException e) {System.out.print("link error,step 1
");}
        try {
            connect=DriverManager.getConnection(link,"root","123456");
        } catch (SQLException e) {System.out.print("link error,step 2,check password
");connect=null;}
        return connect;
    }

    public static void close(Statement sta,Connection connection) {
        if(sta!=null) {
            try {
                ((Connection) sta).close();
            }catch(SQLException e) {
                e.printStackTrace();
            }
        }
        if(connection!=null) {
            try {
                connection.close();
            }catch(SQLException e) {
                e.printStackTrace();
            }
        }
    }