Which access modifier will use variable should be accessed with in a class?
Have you ever wanted to define how people would access some of your properties? You would not want anyone using your underwear. However, your close friends and relatives can use your sweater and maybe your car. Show
Similarly to how you set a level of access to your posessions, Java controls access, too. You want to define the access level for variables, methods and classes depending on which other classes you want accessing them. Java provides 4 levels of access modifiers. This means that you can modify access to a variable, method or a class in 4 ways. These 4 ways are private, public, protected and default. These access modifiers can be applied to fields, methods and classes (Classes are a special case, we will look at them at the end of this artice). Here is a quick overview1 of what the Access Modifiers Table Reference:Private Access ModifierAllows a variable or method to only be accessed in the class in which it was created. No other class beyond the class that created the variable or method can access it. This is closely similar to your internal organs. They are only accessible to the owner. To make a variable or method private, you simply append the private keyword before the variable or method type. Let us use private in a coding example. If a bank wants to provide an interest rate of 10% on it’s loans, it would make sure that the interest rate variable(let us suppose 0The above example creates a variable called name and ensures that it is only accessible within the class from which it was created. Another example for a method is
The above example ensures that the method setAge is accessible only within the class from which it was created and nowhere else. Public Access ModifierThe public access modifier is the direct opposite of the private access modifier. A class, method or variable can be declared as public and it means that it is accessible from any class. Public access modifier can be likened to a public school where anyone can seek admission and be admitted. A public class, method, or variable can be accessed from any other class at any time. For example, to declare a class as public, all you need is:
As such, the Animal class can be accessed by any other class.
Above are ways of specifying a variable and a method as public. The Default Access ModifierThe default access modifier is different from all the other access modifiers in that it has no keyword. To use the default access modifier, you simply use none of the other access modifiers and that simply means you are using a default access modifier. For example, to use the default access modifier for a class, you use
This basically means you are using the default access modifier. The default access modifier allows a variable, method, or class to be accessible by other classes within the same package. A package is a collection of related classes in a file directory. For more information about packages, check out the section on packages. Any variable, method, or class declared to use the default access modifier cannot be accessed by any other class outside of the package from which it was declared.
Above are some ways of using the default access modifier for a variable or method. Don’t forget, the default access modifier does not have a key word. The absence of the 3 other access modifiers means you are using the default access modifier. Protected Access ModifierThe protected access modifier is closely related to the default access modifier. The protected access modifier has the properties of the default access modifier but with a little improvement. A variable and method are the only ones to use the protected access modifier. The little improvement is that a class outside the class package from which the variable or method was declared can access the said variable or method. This is possible ONLY if it inherits from the Class, however. The class from another package which can see protected variables or methods must have extended the Class that created the variables or methods. Note without the advantage of Inheritance, a default access modifier has exactly the same access as a protected access modifier. Examples of using the protected access modifier is shown below:
Access Modifiers on ClassesBy default, classes can only have 2 modifiers:
So this means classes can never be set to 1 or 2?This is logical, why would you want to make a private class? No other class would be able to use it. But sometimes, you can embed a class into another class. These special classes, 3, can be set to private or protected so that only its surrounding class can access it:
In the above example, only the 4 class can use the 5class. This can be useful in some cases.Other classes can never be set to 2 or 1, because it makes no sense. The 2access modifier is used to make things 9 but with the option to be accessible to subclasses. There is no concept such as ‘subpackages’ or ‘package-inheritance’ in java.ADVERTISEMENT ADVERTISEMENT ADVERTISEMENT ADVERTISEMENT If this article was helpful, tweet it. Learn to code for free. freeCodeCamp's open source curriculum has helped more than 40,000 people get jobs as developers. Get started Which access modifier can be used for a variable?Private Access Modifier
Allows a variable or method to only be accessed in the class in which it was created.
Which access modifier can be accessed within a class?For members, there are two additional access modifiers: private and protected . The private modifier specifies that the member can only be accessed in its own class.
Which access modifier can be used to access a variable outside the class and within the package?Public: The access level of a public modifier is everywhere. It can be accessed from within the class, outside the class, within the package and outside the package.
Which access modifier makes variables and methods visible only in the class?Private Access Modifier - Private
Methods, variables, and constructors that are declared private can only be accessed within the declared class itself. Private access modifier is the most restrictive access level.
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