Answer Posted / raju

Arry List defult limit is 10

What are the drawbacks for singleton class?

1036

---

Is minecraft java edition free?

1132

---

What is jit compiler in java?

1127

---

Explain the difference between string, stringbuffer and stringbuilder in java?

1013

---

Can java object be locked down for exclusive use by a given thread?

1009

---

What is meant by overloading?

1076

---

Can a hashset contain duplicates java?

985

---

What are keywords and reserved words in java?

1070

---

What are the advantages of java over C++?

1208

---

Describe what happens when an object is created in java ?

1018

---

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)

1952

---

what is server side caching?

2184

---

If I don't provide any arguments on the command line, then what will the value stored in the string array passed into the main() method, empty or null?

1267

---

What is the Difference between Final Class && Abstract Class?

1088

---

What is ternary operator? Give an example.

1094

---