java - NullPointerException in LinkedHashMap -

i'm creating game. when i'm reading linkedhashmap, gives me npe.

i fill linkedhashmap hm this:

for (string s : line.split("")) {     if (s.contains("*")) {         hm.put(new coordinates(xa-32, ya), "gray");     } else if (s.contains("#")) {         hm.put(new coordinates(xa-32, ya), "black");     }     // other code... } 

later try color hashmap this, , npe:

if ((keycode == keyevent.vk_left || keycode == keyevent.vk_a)     && ispainted && hm.get(new coordinates(x - 32, y)).equalsignorecase("gray")) {     x -= 32; } 

full code here:

• gamepanel.java
• coordinates.java

on line hm.get(new coordinates(x, y - 32)).equalsignorecase("gray")), not possible hm contains newly created coordinates.

when create new object, example coordinates c = new coordinates(x, y - 32);, in memory created object , variable c holds reference memory, not object itself.

because of it, @ code :

coordinates c1 = new coordinates(x, y - 32); //c1 holds reference memory, "a8wgge8h" coordinates c2 = new coordinates(x, y - 32); //c2 holds reference memory, someting "a8w12238h" if (c1 != c2){    system.out.println("yes, true, c1 not c2, there 2 objects same properties, not same, human twins - same, 2 people exists"); } 

therefore cant find in hm.get(new coordinates(x, y - 32)), because not coordinate has same x,y, looks coordinate same reference memory. , cannot exists, because create new object, java associated new memory address, abnbn147 , list/set looks object address abnbn147, cannot stored there, because have created it.

this hm.get(new coordinates(x, y - 32)) return null. if call method on null, ends nullpointerexception, happens calling method equalsignorecase on null object talking about.