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Question

当我尝试编译代码时出现此错误。我不确定它有什么问题，我不明白错误是什么。这是错误消息，后面跟着它说错误的行：

Exception in thread "AWT-EventQueue-0" java.lang.ExceptionInInitializerError
    at g52gui.C_login.<clinit>(C_login.java:9)
    at g52gui.V_login.<init>(V_login.java:6)
    at g52gui.V_login$4.run(V_login.java:181)
...

以及错误的行：

line 9 C_login (controller): private static final C_home controller_home = new C_home();

line 6 V_login (view): private final C_login controller_login = new C_login();

line 181 V_login (view): new V_login().setVisible(true);

似乎问题来自C_home，但那里没有编译错误。

修改

我认为问题可能在这里，在C_login中：

public class C_login {
    private static final V_login view_login = new V_login();
    private static final M_login model_login = new M_login();
    private final static C_home controller_home = new C_home();
    private static final C_registration controller_regi = new C_registration();
    private static final MySQLAccess sql_connection = new MySQLAccess();


    public static void main(String[] args) throws Exception {
        view_login.setVisible(true);
    }

    public static boolean login_button_clicked(String usrn, String psw){
        String login = M_login.login(usrn, psw);
        if (login == "ok"){
            controller_home.start_view(usrn);
            view_login.setVisible(false);
        } else if (login == "fail" ) {
            view_login.error_login();
            return false;
        } else {
            view_login.error_connection();
            return false;
        }
        return false;
    }

我将C_home controller_home视为静态，以便稍后可以访问它。是否还有另一种方法可以解决这个问题？

修改

这是C_Home中的初始化程序：

public class C_home {
    private static final V_home view_home = new V_home();
    private static final M_home model_home = new M_home();
    private String username = "";

    /* attributes for 3d model */
    private BranchGroup sceneBranchGroup = null;
    private RotationInterpolator rotator = null;
    private Canvas3D offScreenCanvas3D = null;
    private ImageComponent2D imageComponent = null;
    private static final int offScreenWidth = 200;
    private static final int offScreenHeight = 200;