Trouble rationalizing use of multi-threading in run of the mill servlets

Question

Hey everybody,
While spending time writing an internal wiki article on servlets for work, I asked myself a very basic question: What does multi-threading buy average servlets where the business logic requires procedural handling of the request?
Don't get me wrong: I appreciate the fact that servlet containers spawning a new thread being less expensive than spawning an entirely new process is helpful and efficient. Coming from a background in PHP, it is great how servlets maintain persistence. However, as more of my coworkers are required to gain proficiency in Java and designing servlets, it is a question that many will ask and aside from having real-time processing of data files and other arduous tasks, I cannot think of any instances of where multi-threading benefits the application.
What are some of the ways that you are using multi-threading with web applications?
How would you explain why and where you would want to use multi-threading to someone?
Thank you in advance for your insight,
Andy

Answer 1

how can we pass arguments to the run ()method?Create classes which implement Runnable that take your runtime parameters as constructor arguments and store them.
eg: if your single thread method is   static void foo (int quantity, String name) {
    for (int i=0; i<quantity; i++) {
      System.out.println(name);
// caller code
  foo(7, "wombats");Then you can make a runnable implementation thus:public class Foo implements Runnable {
  final int quantity_;
  final String name_;
  public Foo (int quantity, String name) {
    quantity_ = quantity;
    name_ = name;
  public void run () {
    for (int i=0; i<quantity_; i++) {
      System.out.println(name_);
// caller code
  new Thread(new Foo(7, "wombats")).start();
You could overload this method to take parameters in
your class that implements the Runnable interface,
and then call the base run() method.I don't get what you mean by this; Runnable is an interface so there is no base class run() method, and a run() overloaded with extra parameters method wouldn't get called by the thread.
Pete