Java job interviews

I would like to collect those stories which one can get on a Java interview.

I want this post to be a collection. I would like to add experience stories which one can get on a Java interview. To start off I add my first job interview experience, but if you have some stories, please let me know, send me an e-mail.

#0 - Junior Java developer

I applied to a small startup company, everything went great. On the first "meeting" I was interviewed by a senior developer and maybe a marketing guy. We used http://collabedit.com. Only one task and at the end some questions on programming. So this is what I was given:

public class Course {
	private final String name;
	private final List<Student> participants;
	private int capacity;
	
	//todo: add whatever is needed to make it compile
}

public class Student {
	private final Integer id;
	private final String name;
	
	//todo: add whatever is needed to make it compile
}

public interface Registration {
	/**
	* Register student to course
	* @param student - Student to be registered
	* @param courseName - Name of the course
	* @return true if student was registered, false otherwise
	*/

	public boolean register(Student student, String courseName);
}

public class ???? implements Registration {
	private List<Course> courses;
	//todo: complete me  
}

// Example usage, course creation
Course c1 = new Course("course1", 10);
Course c2 = new Course("course2", 10);
Course c3 = new Course("course3", 10);
Course c4 = new Course("course4", 10);

List<Course> temp = new ArrayList<>(4);
temp.add(c1);
temp.add(c2);
temp.add(c3);
temp.add(c4);

Registration registration = ????

Student student1 = new Student(1, "Some Name");
//example usage, registration
registration.register(student1, "course1");
registration.register(student1, "course2");
registration.register(student1, "course3");

Of course I had to make it work. After a few days I received an e-mail that the first interview was going well and let's have a second one! I was very happy..... :)

The second one happened the next week and it had 2 parts. The first one was mainly about me. They asked simple questions like how I started programming, what I like most in it, what projects I had, also they had questions on working in a team, etc. The second part was the funniest I think. They gave me math problems.

Get exactly 4 cups of water using a 5-cup pail and a 3-cup pail.
Suppose you had eight identical basketballs. One of them is slightly heavier and you are given a balance scale . Can you find the heavier ball using the scale only 2 times?
There are 100 couples living in a country and people only want boys. Every family continues to have children until they have a boy. If they have a girl, they have another child. If they have a boy, they stop. What is the proportion of boys to girls in the country?

Of course I could find the answers, but I would have not ever thought that They will give me math problems. Are there programmers out there who cannot solve these kind of problems? I would be shocked! It is about simple logic. A programmer must be able to solve these! :)

Anyway, this part of the interview also went well.

Please send me your interview stories, too! :)

2015.07.30.