How can a value from the derived class be assigned to a variable in base class?

No, but a double value can be assigned to a float variable. (You will lose from the precision, obviously.)

A private variable is one that is accessible only to the current class and cannot be accessed by any other class, including the ones that extend from it. A final variable is one that cannot be modified once it is initialized and assigned a value.

Default initial value of extern integral type variable is zero otherwise null.

Just type declare then the variable that you desire to assigned a certain constant value on it. Just type declare then the variable that you desire to assigned a certain constant value on it.

3x+2 x is a variable. A variable is a symbol (x, y, etc...) that does not have an assigned value.

The definition of constant variable is a variable whose value cannot be changed once it has been assigned a value for an experiment. It is the variable held steady, or constant, for a specific experiment.

None. A letter has no numerical value unless it represents a variable and a value is assigned to it.

In C when assigning an integer variable to String variable a compilation error occurs as Incompatible Type Conversion. So that integers cannot get assigned to String variables.

Both increment the value of the variable by one. The difference is the value of the increments expression itself. With preincrement value is taken after incrementing, and with postincrement value is taken before incrementing. Example: Let x have value 5. y = ++x; Both y and x are assigned value 6. Again let x have value 5. y = x++; y is assigned value 5. x is assigned value 6.

it depend on the programming language u use. for instance in c, just decalre the variable and equal it to the value it is to take. eg. my_age=21; /*my_age is the decared variable and 21 is the assigned value*/ //for php $my_age=21; /*my_age is the decared variable and 21 is the assigned value*/ for strings (in php) eg. $my_age="none of ur business" /*$my_age is the variable and the string "none of ur business" is the assigned value*/

Everything is an object, and "typed" based on assignation. Your variable will be given a class when you declare it to be something, and the class will depend on what value you give the variable. It is always an object though, and its class may change if you change its value.

In C a float value can be assigned to an integer variable but an implicit casting occurs when compiler forces a float value to be assigned as an integer. So that the digits after the decimal notation in the float value get loss after assigning a float to an integer. eg: int a=12.356;// Implicit casting occurs printf("%d",a);// when printing a it shows as 12 as an integer

Transient variable can't be serialize. For example if a variable is declared as transient in a Serializable class and the class is written to an ObjectStream, the val ue of the variable can't be written to the stream instead when the class is retrieved from the ObjectStream the value of the variable becomes null

And what is the question? - The value of such an expression will depend on the value assigned to the variable, in this case, "t".

Default values are available for any class or instance variable. If you do not specify a value for a class or instance variable the JVM will provide a default value that will ensure that the system does not end up with any unexpected errors because you used a variable that was not initialized. Ex: Public class Test { int I; } In the above class we have just declared an instance variable called 'I' but we haven't associated any value to it. The JVM automatically assigns 0 as the default value to this variable.

A variable declared as final can't be modified, once a value is assigned.

In math, that refers to an equation which includes a variable. Such an equation may be true, or false, depending on the value assigned to the variable.

Yes, an integer can be assigned as a float value. But it get stored as a float value, that is an implicit type conversion occurs during compilation.Smaller data types are convertible to larger data types. eg: float b=12;// an integer constant is assigned to a float variable printf("%f",b);// when printing b it will print as 12.000000

If it is a class or instance variable, it gets the default value of false. If it is a local variable (inside a method), it doesn't have a value until you explicitly set one.

Fields defined without the "static" keyword.Their value is unique to each instance (object) of a class. Answer Instance variable is a variable declared within the class for which every object of the class has its own value.

Well, at the basic level, class fields, or static fields, as they are called sometimes, belong to the class and not to any particular instance of the class. Class fields can be assigned without instantiation of instance objects of a class. For example: public class ExampleClass { public static String classField = ""; public String instanceField = ""; } I can assign a value to classField just like that: ExampleClass.classField = "new value"; Instance fields, on the other hand, belong to a particular instance of the class. Thus, to assign an instance field a value, you have to first instantiate an object of the class just like that: ExampleClass obj1 = new ExampleClass(); obj1.instanceField = "new value";

The best design strategy would be to provide a protected accessor (getter) that returns the variable either by value or by constant reference. If the derived class needs to mutate the variable, then provide a protected mutator (setter). Only derived classes have protected access to their base classes. However, derivatives can also lower that access to private with respect to their own derivatives, if desired. Even if the variable does not represent a class invariant, it's still best to provide an interface rather than expose an implementation detail outside of the class, whether that exposure is public or protected. In this way the implementation detail may be changed at a future time without affecting any of the consumers of your class (including derivatives), since they will all be using the public or protected interface. So long as that interface remains unchanged, the scope of your internal changes is limited to the class itself, thus you won't break any code that uses your class. If your class already provides a public interface to the variable, then your derived class can obviously make use of that as well. You only need a protected interface when no public interface is provided.

Static variables exist for the entire duration of the program. Therefore a static character variable is a character that exists for the entire duration the program is running. Regardless of where a static variable is declared and initialised, it is physically instantiated and initialised when the program loads. If the variable has function scope, whatever value is currently assigned to the variable will remain in effect the next time that function is called, but only the function can modify the variable. If the variable has class scope, then the variable exists even if no instances of the class have yet been instantiated, but any and all instances share the variable (it is common to the class, not to any one instance of the class). Static class variables must be initialised outwith the class body and outwith any other function body, but can only be modified by the class members (both static and non-static) and by friends of the class. If the variable has file scope, then the variable is a global variable. Global variables are largely frowned upon as there's no way to control what code can modify the value. Passing local function variables to other functions is the preferred method as this gives much greater control over which code can access and/or modify the value, as well as limiting the lifetime of the variable. To ensure the variable exists throughout a program's lifetime (as per a static variable), instantiate the variable from within the program's entry point.

No. To evaluate a variable, you simply take its value. When you assign a value to a variable, the evaluation of that operation is the value of the variable after assignment. There is no calculation required to evaluate a variable, unless that calculation is part of the right-hand operand of an assignment operation, in which case the calculation is evaluated first and the result of that evaluation (the value) is then assigned to the variable which is then evaluated.

undefined means a variable has been declared but has not yet been assigned a value. On the other hand, null is an assignment value. It can be assigned to a variable as a representation of no value. Also, undefined and null are two distinct types: undefined is a type itself (undefined) while null is an object