Test Index

Multi Threading

Question : 29

Total: 44

Given:

public class Letters extends Thread {
  private String name;
  public Letters(String name) { this.name = name; }
  public void write() {
   System.out.print(name);
   System.out.print(name);
  }
  public static void main(String[] args) {
   new Letters("X").start();
   new Letters("Y").start();
  } }

We want to guarantee that the output can be either XXYY or YYXX, but never XYXY or any other combination. Which of the following method definitions could be added to theLetters class to make this guarantee? (Choose all that apply.)

public void run() { write(); }
public synchronized void run() { write(); }
public static synchronized void run() { write(); }
public void run() { synchronized(this) { write(); } }
public void run() { synchronized(Letters.class) { write(); } }
public void run() { synchronized(System.out) { write(); } }
public void run() { synchronized(System.out.class) { write(); } }

Validate

Go to Question:

Prev Question

Next Question