constructor « toString « Java Class Q&A

1. Best way to add a string based constructor to a Java class?    stackoverflow.com

Say I have some class, e.g. Foo:

public class Foo {
    private Integer x;
    private Integer y;

    public Foo(Integer x, Integer y) {
 ...

2. toString method for varargs constructor    stackoverflow.com

I have a varargs constructor like this :

public class Sentence {

   public String[] str;

      public Sentence(Object... text){

        ...

3. Why Exception object's constructor is called instead of toString()?    coderanch.com

4. Help Implement LinkedStack constructor, clone meth and toString method    forums.oracle.com

Hey, I have to write a constructor class LinkedStack that loads the stack from an array parameter and when the constructor is finished, the last array element is supposed to be at the top of the stack. On top of that I have to write a clone method and a toString method for the LinkedStack. I am totally lost with this ...