Java's class method can also be called a static method, which is a method in a class modified with static; because the class method belongs to the entire class, the method body of the class method There cannot be content related to objects of the class.
That is, the class method body has the following restrictions: (Recommended learning: java course)
1. Objects cannot be referenced in class methods Variable;
2. The object method of the class cannot be called in the class method;
3. The super and this keyword cannot be called in the class method;
4. Class Methods cannot be overridden.
Test Case
public class Test {
private int a = 5;
private static int b = 10;
public static void yiStatic()
{
// a = 10;//靜態(tài)方法無(wú)法訪問(wèn)非靜態(tài)成員變量
System.out.println("yiStatic");
}
public void yiInstance()
{
a = 10;
b = 5;//非靜態(tài)方法可以訪問(wèn)靜態(tài)變量
System.out.println("yiInstanc");
}
public void yiInstance2()
{
yiStatic();//非靜態(tài)方法可以訪問(wèn)非靜態(tài)方法
yiInstance();//非靜態(tài)方法可以訪問(wèn)靜態(tài)方法
System.out.println("yiInstance2");
}
public static void yiStatic2()
{
yiStatic();//靜態(tài)方法可以訪問(wèn)靜態(tài)方法
// yiInstance();//靜態(tài)方法不可以訪問(wèn)非靜態(tài)方法
System.out.println("yiStatic2");
}
}Through this test we found that instance methods, that is, non-static methods, can access any variables and methods in the class (including static and non-static) , while only static variables and static methods can be accessed in static methods.
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