Answer / fraz

Lets say you have Employee class

public class Employee{
private String id;
private String name;
..getter/setters..

}

You just have to overide hascode() and equals() method in
above class.

Hi buddy, well i got that there is always a default constructor with abstract class. OK. But why not with interface? Thanks in advance.

2 Answers  

---

What is casting?

5 Answers  

---

Do you know why doesn't the java library use a randomized version of quicksort?

0 Answers  

---

What is a java applet? What is an interface?

0 Answers  

---

The following program reads data (details of students) from a file named students.txt and converts it into e-mail addresses. The results are written to a file named studentemail.txt. students.txt consists of a number of lines, each containing the data of a student in colon delimited format: Last Name:First Name:Student Number Each input record is converted to an e-mail address and written to studentemail.txt in the following format: the first character of the last name + the first character of the first name + the last four digits of the student number + “@myunisa.ac.za” import java.io.*; public class EmailConverter { public static void main(String[] args) throws IOException { BufferedReader input = new BufferedReader(new FileReader ("students.txt")); PrintWriter output = new PrintWriter(new FileWriter ("studentemail.txt")); String line = input.readLine(); while (line != null) { // Extract the information for each student String[] items = line.split(":"); // Generate the email address String email = "" + items[0].charAt(0) + items[1].charAt(0) + items[2].substring(4,8) + "@myunisa.ac.za"; email = email.toLowerCase(); // Output output.println(email); line = input.readLine(); } input.close(); output.close(); } } Rewrite the class so that it handles possible errors that may occur. In particular, it should do the following: • It should catch at least three appropriate exceptions that might occur, and display suitable messages. • At this stage, the program will not run correctly if there is an empty line in the input file. Change the program so that if an empty line is encountered, an exception is thrown and the empty line is ignored. This exception should be handled with the display of a suitable error message. • Before the e-mail address is added to the output file, check if the student number has 8 digits. If not, throw an InvalidFormatException (which the program should not handle itself)

0 Answers  

---

---

Can we catch more than one exception in single catch block?

0 Answers  

---

what is associative array

1 Answers   Tech Mentro,

---

What are the difference between string, string builder, and string buffer in java?

0 Answers  

---

Explain covariant method overriding in java.

0 Answers  

---

What is difference between call by value and call by reference?

0 Answers  

---

What is singleton class and how can we make a class singleton?

0 Answers  

---

hoe can u call a constructor of a private classs to other inherited claa??

1 Answers  

---