我正在嘗試學習靜態工廠方法及其相對于建構式的優勢，但我的代碼拋出了一個錯誤，即最終的字串名稱未分配值（名稱可能未初始化）
public class Main {
public final String name;
private final String email;
private final String country;
public Main(String name, String email, String country) {
this.name = name;
this.email = email;
this.country = country;
}
public Main() {}
static Main createName(String name, String email) {
return new Main(name, email, "Argentina");
}
public static void main(String[] args) {
Main obj = new Main();
createName("vipin", "vipin.com");
System.out.println("This is name: " obj.name "\n" "This is email address: "
obj.email "\n" "This is country: " obj.country);
}
}
uj5u.com熱心網友回復：
改變：
Main obj = new Main();
createName("vipin", "vipin.com");
到：
Main obj = createName("vipin", "vipin.com");
并忘記沒有正確初始化欄位的無引數建構式。
uj5u.com熱心網友回復：
實體變數由其默認值初始化，除非它是final在實體化物件時。如果您從它的建構式之一初始化它，它就不能在建構式中初始化。因此，建議final實體變數應該在建構式中初始化。
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