Question

Eclipse will give an error, “The left-hand side of an assignment must be a variable”, when I try something like:

public class Thing{

  String a1;
  int a2;

  public void meth(){
    Thing A = new Thing();
    this = A;
  }
}

I had to assign each variable (this.a1 = A.a1; this.a2 = A.a2;) as a work around.

Are there other ways to do this without going through each variable field?
And if this is not a variable what is it called?

Answer 1

this is a pseudo-variable that points to the current instance of the object, it can not be reassigned. It’s also considered a keyword in the language, according to section §3.9 of the Java Language Specification.