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Q) Write about access specifie?



A)
 ->an access specifier is a keyword that specifies accecibility mode or visibility mode of the members of the class (come times class itself)
->in java, we 3 access specifiers
1. Private
2. Public
3. Protected
->in java, we have 4 accesibility or visibility modes
1. Private mode
2. Default mode
3. Protected mode
4. Public mode

Default access specifier:
If we don’t apply any access specifier to a member of a class, that member has default accessibility mode. It also known as “package level accessibility”.

Private access specifiers:
->private access specifier or access modifier is meant for providing private visibility mode to the variable and method of a class.
->”private” provides “class level visibility” I.e. other class methods can’t access even though that class is in same package. Only same class methods can access.
->Accessibility achieved through “access specifier”.
->Accessibility achieved through ”import” statement.

Note:
In c,c++ if no access specifier is specified then it act as “private mode” but in java “default mode” is applied when any access specifier is not specified.

->I.e. if a member of a class has private visibility mode, only the methods of that class can access that member.
Protected access specifier:
this modifier provides class level, package level and child class level visibility to the members of the class.
Ex:
class A extends B
{
   Protected y()
     {
        
     }

}
class B
{
   a()

     {
     y();   
     }

}
Public access specifier:
it provides java environmental level visibility to the member of java class.

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