1.What is the purpose of the Runtime class?
Latest answer: The java runtime system can be accessed by the Runtime class. The runtime information – memory availability, invoking the garbage collector is possible by using Runtime class............ Read answer
2.What is the difference between a static and a non-static inner class? Latest answer: Like static methods and static members are defined in a class, a class can also be static. To specify the static class, prefix the keyword ‘static’ before the keyword ‘class’........... Read answer
3.What is the difference between the String and StringBuffer classes? Latest answer: String class is immutable. The characters of string objects can not be changed / modified. StringBuffer is mutable. The characters of StringBuffer objects can be modified / changed.......... Read answer
4.What is the Dictionary class?
Latest answer: The Dictionary class is an abstract class. The class maps keys to values. The classes such as HashTable are the sub classes of the abstract class Dictionary. The key and values are objects. The key and value are non-null objects............... Read answer
5.What is the ResourceBundle class?
Latest answer: A ResourceBundle is a group of related sub classes which are sharing the same base name. For example, ButtonLabel is the base name. All the characters following the base name indicates the following elements respectively........... Read answer
6.What is the Vector class?
Latest answer: The Vector class implements an incremental array of objects. The vector components can be accessed using an integer index. The size of a Vector increases or decreases as needed to accommodate the items......... Read answer
7.What is the SimpleTimeZone class?
Latest answer: SimpleTimeZone is a concrete subclass of TimeZone class. The TimeZone class represents a time zone, that is to be used with Gregorian calendar.......... Read answer
8.What is the purpose of the System class?
Latest answer: System class is provided with useful fields (static members) that are pertaining to the environment. Standard input,output and error output streams are provided with System class. These are used to access the externally defined properties and environment variables............ Read answer
9.How are this() and super() used with constructors?
Latest answer: this() constructor is invoked within a method of a class, if the execution of the constructor is to be done before the functionality of that method............ Read answer
10.What is the purpose of finalization?
Latest answer: Finalization is the facility to invoke finalized() method. The purpose of finalization is to perform some action before the objects get cleaned up. This method performs the required cleanup before the garbage collection............. Read answer
11.What is the difference between the File and RandomAccessFile classes? Latest answer: The File class is used to perform the operations on files and directories of the file system of an operating system. This operating system is the platform for the java application that uses the File class objects............ Read answer
12.What is a StringBuffer class and how does it differs from String class? Latest answer: StringBuffer is thread safe, where as StringBuilder is not. In other words, StringBuffer class is synchronized and StringBuilder class is not synchronized.......... Read answer
13.Explain how to implement shallow cloning and deep cloning. Latest answer: Implementing Shallow cloning: In shallow cloning, a new object is created which is an exact copy of the original object. It is a bit-wise copy of an object. In case any field of the object is referred to other objects, only the references are copied but not the objects............ Read answer
14.What is an abstract class? | Explain the difference between abstract class and interfaces. Latest answer: An abstract class defines an abstract concept which can’t be instantiated. We can’t create object of...
Please join StudyMode to read the full document