UNIVERSITY EXAMINATIONS: 2018/2019 EXAMINATION FOR DIPLOMA IN INFORMATION TECHNOLOGY DIT 410: JAVA PROGRAMMING MODE: FULL TIME/PART TIME ORDINARY EXAMINATIONS DATE: MARCH, 2019 TIME: 2 HOURS INSTRUCTIONS: Answer question ONE and any other TWO. QUESTION ONE[30 MARKS] a) Give FOUR advantages of Java as an object oriented programming language. 4 Marks b) Explain the FIVE states of a thread in Java programming. 5 Marks c) Describe the following terms. i. Byte code ii. Interface iii. Package. iv. Class v. Method 5 Marks d) Java has both primitive and reference types. Name an appropriate primitive data type to represent each of the follow: i. The number of students in a university ii. The average age of a student in the university iii. Whether or not a student has enrolled iv. The response of the asked to type ‘y’ to continue or ‘n’ to exit. 4 Marks e) Write a Java program to read six characters, store then in an array, sort then display in descending order. 8 Marks f) For each of these expressions, determine its result. Assume the value of text is a string “Java Programming” String text = “Java Programming”; i. text.substring(0,4) ii. text.length() iii. text.substring(8,12) iv. text.substring(0,1) + text.substring(7,9) 4 Marks QUESTION TWO[20 MARKS] a) What is an exception as used in Java programming? 2 Marks b) What is the difference between checked and unchecked exceptions? 4 Marks c) Briefly explain String Buffer as used in Java programming. 2 Marks d) Briefly outline any three methods used in String Buffer class. 6 Marks e) Write a java program to read a non-zero integer then reverse its digits then display the resultant number e.g. if the user keys in 2019 the program will reverse the digits and display 9102. 6 Marks QUESTION THREE [20 MARKS] a) Define a wrapper class as used in java langauge. 3 Marks b) Complete the following table of primitive types using the corresponding wrapper class for each type. 5 Marks. c) Explain the concept of method overloading as used in java programming. 4 Marks d) Write a java program to demonstrate the use of method overloading 8 Marks QUESTION FOUR [20 MARKS] a) Differentiate between a local variable and instance variable in java. 2 Marks b) Write a Java program to calculate the area and circumference of a circle, given the following 8 Marks c) In java language, a statement can be defined as a complete instruction to a computer to perform some task. In this regard, describe the following types of java statements. i. Empty statement. ii. Selection statetement. iii. Jump statement. 6 Marks d) Write a java program to print integers that are multiples of five between 2 and 61. 4 Marks QUESTION FIVE [20 MARKS] a) Differentiate between order of precedence and associativity as used in java operators. 2 Marks b) The table below shows the water billing criteria in a certain town. Use it to answer the question that follows. Write a java program that accepts the current and previous meter readings, the program then computes and outputs amount pyable by client. Note that a standing charge of Ksh.120 is chargeable for all customers regardless of the units used. 9 Marks c) Describe the steps involved in handling exceptions in Java. 4 Marks d) Using an example describe constructor method as used in Java programming. 5 Marks