More than 3000 questions in repository. There are more than 900 unanswered questions. Click here and help us by providing the answer. Have a video suggestion. Click Correct / Improve and please let us know.
Q845. Shouldn't we make a class with all static members is its just expected to be executed as a standalone program with just one thread. Moreover Lets assume that there is no runtime Polymorphism required and there is no need for serialization ?
Ans. Still No in case we are making use of inheritance. we may have problem wherein we have program flow moving across common inherited method and specific methods of the derived class. call made to another static method in the parent class will only access the static class of the Parent class irrespective of the call from any of the derived class.
Help us improve. Please let us know the company, where you were asked this question :
Ans. AssertionError is actually a fatal fault or a bug in the program. We may not like to continue program , request or thread execution if this error occurs as this condition is the assumption to continue further execution.
Help us improve. Please let us know the company, where you were asked this question :
Ans. No, Java runs on a virtual machine called JVM and hence doesn't embed well with the underlying hardware. Though we can create a platform independent system software but that would be really slow and that's what we would never need.
Help us improve. Please let us know the company, where you were asked this question :
Q850. Shall we keep the enumeration name in all capital letters as it contains all constants ?
Ans. Enum is actually a class with pre defined constants. So enum name should follow the convention of the Class name. Though the constant names or the Enum variables should follow the convention of having all capital letters.
Help us improve. Please let us know the company, where you were asked this question :
Q851. In majority of the situations it won't make much sense whether you append this with the instance method call.Can you tell a situation wherein this keyword would make sense in a instance method ?
Ans. Within instance method of the parent class that has other multiple methods that have been overridden by the derived classes.
In such case a simple method call from the common method will always be made to the method definition in the parent class. But If we use this.methodCall , this will be polymorphic and will be made to the respective derived object overriding method.
Help us improve. Please let us know the company, where you were asked this question :
Ans. Any reference in java that doesn't point to any object , gets assigned null i.e is a reference to null. Two object references in java are treated equal if they point to the same memory. That's Why null == null results true.
Help us improve. Please let us know the company, where you were asked this question :
Ans. Its a specification that guides the implementation of ORM frameworks. Implementations abiding by the specification would mean that one can be replaced with other in an application without much hassle. Only the Features that are added over the specification needs to be taken care of if any such change is made.
Help us improve. Please let us know the company, where you were asked this question :
Ans. This is an informative annotation that specify that the interface is a functional interface. A Function Interface has only one abstract method and many default methods. Compiler generates an error if the interface specified with the annotation doesn't abide by the specifications for functional interface.
Help us improve. Please let us know the company, where you were asked this question :
Ans. Its used to execute last command. Yes this can be used with other string to execute new command. For eg - if ls was the last command, We can execute !! -l for having the long listing.
Help us improve. Please let us know the company, where you were asked this question :
Ans. ClassPath is the path where Java looks for class files to resolve the dependencies. For example - If you are using a class "xyz" in your code and have specified the respective import, Where should Java look for the definition of xyz. Java determines using the class path settings.
Help us improve. Please let us know the company, where you were asked this question :
Ans. Final makes sure that the value doesn't change after initialization and static makes sure that there is only one copy that can be shared across objects.
Making it non static will unnecessarily create a different copy per object wherein the same value will kept for all copies ( as its final and cannot be changed ).
Help us improve. Please let us know the company, where you were asked this question :
Ans. In case we specify them explicitly we can have control over constraint name as otherwise they will be system generated. It provides an ease in case we plan to drop the constraint in future.
Help us improve. Please let us know the company, where you were asked this question :
More than 3000 questions in repository.
Discuss 
maven install build management
expert
rare
Asked in 2 Companies
Not frequently asked as it was introduced with Java 8.
Try 1 Question(s) Test
Which access specifiers can be used with top level class ?
