java - Loop through array of objects inside the class -

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i having trouble looping through array objects, inside class. wrote little demo here can follow:

tank tanks[] = new tank[2]; tanks[0] = new tank(); tanks[1] = new tank(); tanks[0].dostuff(tanks);  dostuff(tank[] tanks) {     (int = 0; < tanks.length; i++) {         if (tanks[i].equals(this)) continue;         // stuff     } }

so, have array type tank. call method dostuff inside tank class. method takes array , loops through it. , want stuff every tank not current instance of class. hope can make sense out of code , description.

the problem nullpointerexception if (tanks[i].equals(this))

what doing wrong here?

that means tanks[i] null. (or overridden equals() method has bug)

you need check that.


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