未在ActionListener中初始化的变量

Question

我正在尝试让该程序打印选择的浇头和硬皮，以现在设置的方式，它仅打印名称。 我尝试将所有字符串初始化为空字符串“”。 但是，无论单击了什么按钮，即使支持更改语句，该字符串也始终为空。

这是代码

public void actionPerformed(ActionEvent e) {
    if(e.getSource() == output){    
        String str2, str3, str4, str5;
        String str1 = txtName.getText();
        if(e.getSource() == optThick){
            str2  = "thick crust";
        }
        else if (e.getSource() == optThin){
             str2 = "thin crust ";
        }
        if(e.getSource() == cbCheese){
            str3 = "Cheese ";
        }
        if(e.getSource() == cbOlives){
             str4 = "Olives ";
        }
        if(e.getSource() == cbTomatoes){
             str5 = "Tomatoes ";
        }

        textArea.setText("Name : " + str1 + "\n" + "Crust: " + str2 + "\n" + "Toppings: " + str3 + str4 + str5); 
    }
}
}

Answer 1

if(e.getSource() == output){    
       // code omitted 
}

您所有的if语句都在外部语句内。 是吗

Answer 2

如果有人想知道，这就是我如何使其工作。

public void actionPerformed(ActionEvent e) {
    if(e.getSource() == output){    
        String str2 = "", str3 = "", str4 = "", str5 = "";
        String str1 = txtName.getText();
        if(optThick.isSelected()){
            str2  = "Thick crust";
        }
        else if (optThin.isSelected()){
             str2 = "Thin crust ";
        }
        if(cbCheese.isSelected()){
            str3 = "Cheese ";
        }
        if(cbOlives.isSelected()){
             str4 = "Olives ";
        }
        if(cbTomatoes.isSelected()){
             str5 = "Tomatoes ";
        }

        textArea.setText(String.format("Name: %s \nCrust: %s\n Toppings: %s%s%s ",str1, str2, str3, str4, str5)); 
    }
}