[Solved] Spring Mvc method argumrnts

by


This is basic Java and has nothing to do with Spring. Local variables and method parameters are initialized differently.

For a method parameter the initialization is implicit because you must give some value to the method call. Example:

// Declaration
public String showForm(Model theModel) {
}

// Call
showForm(null);

You cannot ommit the argument and so the method parameter is initialized with the value that you pass to the method call.

For a local variable it is different. If you just declare it without any value assignment the variable is not initialized. The following code would compile:

public String showForm() {
  // Note the initialization with null!
  Model theModel = null;
  Student student = new Student();
  theModel.addAttribute("student", student);
  return "student-form";
}

Anyway, that would cause a NPE at runtime of course.

2

solved Spring Mvc method argumrnts