How to use Builder pattern as described by Joshua Bloch's version in my ModelInput class?

Question

I am trying to use Builder Pattern for my below class.. Initially I was using constructor of my class to set all the parameters but accidentally I came across Builder pattern an

Answer 1

To add to what the others have written:

In order to make your class immutable, you need to make parameterMap variable immutable as well. You can do that when the ModelInput class is instantiated:

private ModelInput(Builder builder){
  this.userid = builder.userid;
  this.clientid = builder.clientid;
  this.pref = builder.pref;
  this.parameterMap = Collections.unmodifiableMap(builder.parameterMap);
  this.timeout = builder.timeout;
  this.debug = builder.debug;
}

Notice the use of Collections.unmodifiablemap();

You'll also need to make your Preference instance immutable, or at least make it known that it is in fact not immutable.