Interview Queastions

1.      How to overload methods?

2.      How to use method overloading for printing different types of array?

3.      How to use method for solving Tower of Hanoi problem?

4.      How to use method for calculating Fibonacci series?

5.      How to use method for calculating Factorial of a number?

6.      How to use method overriding in Inheritance for subclasses?

7.      How to display Object class using instanceOf keyword?

8.      How to use break to jump out of a loop in a method?

9.      How to use continue in a method?

10.  How to use Label in a method?

11.  How to use enum & switch statement ?

12.  How to make enum constructor, instance variable & method?

13.  How to use for and foreach loop for printing values of an array ?

14.  How to make a method take variable lentgth argument as an input?

15.  How to use variable arguments as an input when dealing with method overloading?

16.  How to convert an array into a collection?

17.  How to compare elements in a collection?

18.  How to convert a collection into an array?

19.  How to print a collection?

20.  How to make a collection read-only?

21.  How to remove a specific element from a collection?

22.  How to reverse a collection?

23.  How to shuffle the elements of a collection?

24.  How to get the size of a collection?

25.  How to iterate through elements of HashMap?

26.  How to use different types of Collections?

27.  How to use enumeration to display contents of HashTable?

28.  How to get Set view of Keys from Java Hashtable?

29.  How to find min & max of a List?

30.  How to find a sublist in a List?

31.  How to replace an element in a list?

32.  How to rotate elements of the List?

33.  How to sort an array and search an element inside it?

34.  How to sort an array and insert an element inside it?

35.  How to determine the upper bound of a two dimentional array?

36.  How to reverse an array?

37.  How to write an array of strings to the output console?

38.  How to search the minimum and the maximum element in an array?

39.  How to merge two arrays?

40.  How to fill (initialize at once) an array?

41.  How to extend an array after initialisation?

42.  How to sort an array and search an element inside it?

43.  How to remove an element of array?

44.  How to remove one array from another array?

45.  How to find common elements from arrays?

46.  How to find an object or a string in an Array?

47.  How to check if two arrays are equal or not?

48.  How to compare two arrays?

49.  How to print summation of n numbers?

50.  How to get the first and the last element of a linked list?

51.  How to add an element at first and last position of a linked list?

52.  How to convert an infix expression to postfix expression?

53.  How to implement Queue?

54.  How to reverse a string using stack?

55.  How to search an element inside a linked list?

56.  How to implement stack?

57.  How to swap two elements in a vector?

58.  How to update a linked list?

59.  How to get the maximum element from a vector?

60.  How to execute binary search on a vector?

61.  How to get elements of a LinkedList?

62.  How to delete many elements from a linkedList?

63.  How to format time in AM-PM format?

64.  How to display name of a month in (MMM) format ?

65.  How to display hour and minute?

66.  How to display current date and time?

67.  How to format time in 24 hour format?

68.  How to format time in MMMM format?

69.  How to format seconds?

70.  How to display name of the months in short format?

71.  How to display name of the weekdays?

72.  How to add time to Date?

73.  How to display time in different country's format?

74.  How to display time in different languages?

75.  How to roll through hours & months?

76.  How to find which week of the year?

77.  How to display date in different formats ?

78.  How to create directories recursively?

79.  How to delete a directory?

80.  How to get the fact that a directory is empty or not?

81.  How to get a directory is hidden or not?

82.  How to print the directory hierarchy?

83.  How to print the last modification time of a directory?

84.  How to get the parent directory of a file?

85.  How to search all files inside a directory?

86.  How to get the size of a directory?

87.  How to traverse a directory?

88.  How to find current working directory?

89.  How to display root directories in the system?

90.  How to search for a file in a directory?

91.  How to display all the files in a directory?

92.  How to display all the directories in a directory?

93.  How to compile a java file?

94.  How to run a class file?

95.  How to debug a java file?

96.  How to set classpath?

97.  How to view current classpath?

98.  How to set destination of the class file?

99.  How to run a compiled class file?

100.                      How to check version of java running on your system?

101.                      How to set classpath when class files are in .jar file?

102.                      How to use finally block for catching exceptions?

103.                      How to use handle the exception heiarchies?

104.                      How to use handle the exception methods?

105.                      How to use handle the runtime exceptions?

106.                      How to use handle the empty stack exception ?

107.                      How to use catch to handle the exception?

108.                      How to use catch to handle chained exception?

109.                      How to use handle the exception with overloaded methods ?

110.                      How to handle the checked exceptions?

111.                      How to pass arguments while throwing checked exception?

112.                      How to handle multiple exceptions (devide by zero)?

113.                      How to handle multiple exceptions (Array out of bound)?

114.                      How to use handle the exception with overloaded methods ?

115.                      How to print stack of the Exception?

116.                      How to use exceptions with thread?

117.                      How to create user defined Exception?

118.                      How to compare paths of two files?

119.                      How to create a new file?

120.                      How to get last modification date of a file?

121.                      How to create a file in a specified directory?

122.                      How to check a file exist or not?

123.                      How to make a file read-only?

124.                      How to renaming a file ?

125.                      How to get a file's size in bytes?

126.                      How to change the last modification time of a file ?

127.                      How to create a temporary file?

128.                      How to append a string in an existing file?

129.                      How to copy one file into another file?

130.                      How to delete a file?

131.                      How to read a file?

132.                      How to write to a file?

133.                      How to reset the pattern of a regular expression?

134.                      How to match duplicate words in a regular expression?

135.                      How to find every occurance of a word?

136.                      How to know the last index of a perticular word in a string?

137.                      How to print all the strings that match a given pattern from a file?

138.                      How to remove the white spaces?

139.                      How to match phone numbers in a list to a certain pattern?

140.                      How to count a group of words in a string?

141.                      How to search a perticular word in a string?

142.                      How to split a regular expression?

143.                      How to count replace first occourance of a String?

144.                      How to check check whether date is in proper format or not?

145.                      How to validate an email address format?

146.                      How to replace all occurings of a string?

147.                      How to make first character of each word in Uppercase?

148.                      How to display text in different fonts?

149.                      How to draw a line using GUI?

150.                      How to display a message in a new frame?

151.                      How to draw a polygon using GUI?

152.                      How to display string in a rectangle?

153.                      How to display different shapes using GUI?

154.                      How to draw a solid rectange using GUI?

155.                      How to create a transparent cursor?

156.                      How to check whether antialiasing is enabled or not?

157.                      How to display colours in a frame?

158.                      How to display a pie chart using a frame?

159.                      How to draw text using GUI?

160.                      How to compare strings?

161.                      How to search last occurance of a substring inside a substring?

162.                      How to remove a particular character from a string?

163.                      How to replace a substring inside a string by another one ?

164.                      How to reverse a String?

165.                      How to search a word inside a string?

166.                      How to split a string into a number of substrings ?

167.                      How to convert a string totally into upper case?

168.                      How to match regions in a string?

169.                      How to compare performance of two strings?

170.                      How to optimize string creation?

171.                      How to format strings?

172.                      How to concatenate two strings?

173.                      How to get unicode of strings?

174.                      How to buffer strings?

175.                       How to display Object class using instanceOf keyword?

JDBC

1.      How to establishing a connection with Database?

2.      How to Create, edit & alter table using Java?

3.      How to display contents of table ?

4.      How to update, edit & delete rows ?

5.      How to search in the database using java commands?

6.      How to sort elements of a column using java commands?

7.      How to combine data from more than one tables?

8.      How to use commit statement in Java?

9.      How to us prepared statement in Java?

10.  How to set & rollback to a savepoint ?

11.  How to execute a batch of SQL statements using java?

12.  How to use different row methods in java?

         13.How to use different column methods in java?

Placement queastions :

1)           Write the code to iterate the elements of Hashmap?

2)           Write down the syntax to get Calendar object?

3)           What is the capacity of StringBuffer by default?

4)           Write a syntax to create ThreadGroup object and add three threads to that?

5)           Write a program to sort the objects of Person(name, age, sal) based on name, if names are same then based on salary?

6)       How to set classpath when class files are in .jar file?

7)   wriate program to  reverse elements of the List?

8)   Write a program  to copy one file into another file?

9)   How to use method overloading for printing different types of array?

10)               Write a Program to convert an array into a collection?

11)                Write a Program  to compare elements in a Arraylist by using derived data tyes?

12)     How to make enum constructor, instance variable & method?

13)               How to use for and foreach loop for printing values of an array ?

14)               How to make a method take variable lentgth argument as an            input?

15)               Write a syntax to view current classpath

16)               How to check a thread has stop or not?

17)               How to display all running Thread?

18)               Why is used for this and super as first statement?

19)               How to use handle the exception with overloaded methods ?

20)               How to use catch to handle chained exception?

21)               How to use finally block for catching exceptions?

22)               What are the default contracters?