Why are these Java enums changing values? -

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I have a problem creating a list of objects based on a condition at enum . It seems that after completing the list, every item in the list is equal to the last item.

This is a classic matter of different contexts pointing to the same object, but I do not know how to avoid it:

While I have done everything while maintaining readability, The number of things I keep: 

  public square fu (digit [] array = new issue [2]; ArrayList & lt; foo> foozlets; foo () {array [0] = Digit Zero; Fuzzlets = New Arreelist & lt; Foo & gt; ();} Foo (Foo old, numeral number) {this.array = old.array; \\ This line is a problem, Or array should be called? Array [1] = number;} public static zero main (string [] args) {Foo f = new Foo (); System.out.println ("initial fu:"); println (f); f .listFoozlets ();} zero list for Foozlets () (for digit: digit.values ​​()) {if (k == digit. TWO || k == digit.five) {foozlets.add (new fu ( This, K)); System.out.println ("** Foozlet is being added"); Fu Fu = New Foo (this, K); Println (foo);}} System.out.println (" ** Foozlets ** list for "); (Fu Fu: Fuzletts) {System.out.println (foo);}} public string toString () {return array [0] .toString () +" "+ + Leading [1] .toString (); }} Output is:  
  Initial Fu: Zero Zero ** Foozlet: {ZERO, ONE, TWO, THREE, FOUR, FIVE}  
 
 Being added ** two pairs ** Foozlet being added ** zero FIVE ** list of Foozlets ** zero five zero five

If someone can explain why Fu list changes, and how can I create a list that does not change, I will be grateful.

Edit: OK, I see the problem is now really, in a very big program, I have a lot of array, and I have a new foo I want to keep old information on making I have changed this code that there is additional information to reflect that I want to keep. How can I complete it?

This is a small criminal: 

  Fu (Fu old, issue Number) {this.array = old.array; Array [0] = number; }

You are copying the reference to the old foo array, and then changing the values ​​in that array.

Why do you do so even though there is an array of size 1 rather than just a digit / <>? If you really want the array, you probably want to clone it instead of just copying the reference, but we can not really tell what the intention is.

Here is a small example: 

  value points {zero, one, two, three, four, five} public squares (numeric [] array = new digit [ 1]; Foo () {array = 0] = digit. Zoro;} fu (foo old, numeral number) {this.array = old.array; array [0] = number;} public string toString () {return array [0] .toString ();} Public static zero main (string [] args) {Foo f = new Foo (); Println (f); Fu other = new Foo (F, digit.one); Println (f) ;}}

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