为什么您不能在Java中将类声明为静态类?
最佳答案
只有嵌套的类可以是静态的。这样,您可以使用嵌套类而无需外部类的实例。
class OuterClass {
public static class StaticNestedClass {
}
public class InnerClass {
}
public InnerClass getAnInnerClass() {
return new InnerClass();
}
//This method doesn't work
public static InnerClass getAnInnerClassStatically() {
return new InnerClass();
}
}
class OtherClass {
//Use of a static nested class:
private OuterClass.StaticNestedClass staticNestedClass = new OuterClass.StaticNestedClass();
//Doesn't work
private OuterClass.InnerClass innerClass = new OuterClass.InnerClass();
//Use of an inner class:
private OuterClass outerclass= new OuterClass();
private OuterClass.InnerClass innerClass2 = outerclass.getAnInnerClass();
private OuterClass.InnerClass innerClass3 = outerclass.new InnerClass();
}
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