Spiegel: create Java objects with Java objects

Spiegel is a library that allows you to create and modify the state of Java objects using objects. A class that implements Spiegel's interfaces can be asked these questions:

• What elements do I need to create a new instance of this class?
• What are their possible values?
• What elements of an object's state can I modify?

All these questions can be answered (more or less) using Java's reflection capabilities. Spiegel is a wrapper around these capabilities to make their use easier.

Example

Suppose you have a class like this one:

class Foo
{
  int a;
  int b;
  Bar c;
  
  public Foo(int a, String b, Bar c)
  {
    this.a = a;
    this.b = b.length();
    this.c = c;
  }
}

A user in your program