2012-05-15 34 views
-1

我有一個項目與數據庫工作,我有一些主要的類,如學生,模塊,招生和更多的3類來管理它們。這裏的問題是,如何獲得這個方法的價值

在課堂上的學生我有這樣的代碼

私人字符串ID;

@DomainConstraint(optional = false, mutable = true, type = Type.String, length = 50) 
private String name; 

@DomainConstraint(optional = false, mutable = true, type = Type.String, length = 20) 
private String dob; 

@DomainConstraint(optional = false, mutable = true, type = Type.String, length = 50) 
private String address; 

@DomainConstraint(optional = false, mutable = true, type = Type.String, length = 50) 
private String email; 

private static int autoIncrementInt = 0; 

public Student(String name, String dob, String address, String email) { 
    this.name = name; 
    this.dob = dob; 
    this.address = address; 
    this.email = email; 
    idGenerator(); 
} 

但在類EnrolmentManager,我要以學生的名義報名參加他們的課程這樣

public void load() throws SQLException { 
    Connection con; 
    Properties connectionProps = new Properties(); 
    // set up properties, e.g. user name/password 
    con = DriverManager.getConnection("jdbc:derby:courseman;create=false", connectionProps); 
    Statement stmt = con.createStatement(); 
    ResultSet rs = stmt.executeQuery("SELECT Student.name as studentName, Module.name as Modulename, Enrolment.internalMark,Enrolment.examMark FROM Student,Module,Enrolment WHERE Student.id=Enrolment.sid AND Module.code=Enrolment.mcode"); 

    while (rs.next()) { 
     String s = rs.getString("studentName"); 
     String m = rs.getString("Modulename"); 
     double y = rs.getDouble("internalMark"); 
     double d = rs.getDouble("examMark"); 
     Enrolment e = new Enrolment(s, m, y, d); 
     enrolments.add(e); 
    } 
} 

錯誤在這裏,因爲在班招生我有它的構造是

public Enrolment(Student stu, Module module,Double internalMark, Double examMark) { 
    this.student = stu; 
    this.module = module; 
    this.internalMark = internalMark; 
    this.examMark = examMark; 
    finalGradeGenerator(); 
} 

因此在類EnrolmentManager,它有一個錯誤是構造函數註冊是不明確的。你能幫我解決這個問題,謝謝

+3

我們可以看到招生類代碼? – buymypies

回答

1

招生類的構造函數期待Studentstu)& Module對象(module)作爲參數,但是你把它們解析爲String對象。

+0

它也期望學生的一個例子 – Weeman

+0

也是這樣!謝謝。編輯。 – buymypies

0

這是因爲您的招生班期待模塊和學生作爲您給2個字符串的參數。

//下面是實際構造

public Enrolment(Student stu, Module module,Double internalMark, Double examMark) 

但你逝去的

public Enrolment(String stu, String module,Double internalMark, Double examMark) 
+0

他實際上通過註冊(字符串,字符串,雙,雙) – Weeman

+0

@weeman我編輯過 –