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I see what you mean, if the Asteroid is class is being removed it would make sense why I was getting a null pointer. Hopefully I'll get a chance to get it working tonight. Thanks.

thanks

Thx a lot it works with this!

I think you should read the tutorials, especially #6.

What part are you having trouble with?

Remove the following lines: 12, 15 through 19, 23 & 24, 26 through 28, 48 through 57, 70 and 105. Line 12: not needed because the variable defaults to zero; Line 15 through 19: does not do anything and looks out of place; Line 23 & 24: not needed because the variables default to zero; Lines 26 through 28: variable is not used anywhere in the class Lines 48 through 57: belongs in the Moon world class code Line 70: meaningless where placed (not used in method) Line 105: useless if changing worlds.

The Java tutorials is the best place to start. Begin with the second section on the left, named Trails Covering the Basics.

I am not sure what it really means, either. I am quite sure it would not even compile as written. The methods 'normalMan' and 'manOnFire' are both showing that they are to return a boolean type value, but no values are being returned at all. Change both occurances of 'boolean' to 'void' and it will compile. Then, you will need an 'act' method to check for collision; and when the collision occurs call one of the two methods. You should call the other method in the constructor block to initially set the image of the actor.

Thank you so much I appreciate the help. Going to try inserting these now and keep my fingers crossed I do it right.

Looks like you might run into either a nullPointerException in your 'fire' method (around line 122 of the Rocket class or an illegalStateException in the 'canSee' method of the Mover class when the rocket hits an asteroid. The rocket is removed from the world when it hits an asteroid, so any intersect checking (or use of 'getX' or 'getY') will fail and any 'getWorld' call will return null. To avoid these possible errors, change your 'act' method in the Rocket class to:

What's not obvious is that a method that returns an int looks like an overloaded method for getRandomNumber that returns a boolean. Never noticed getRandomNumber being used in that context.

ohhhhhh thanks.

Click "Documentation" above and then see the links in the "Reference" section. You are perhaps thinking of the PDF version.

If the wombat was placed in the top-left square initially, it would not be too difficult to program it to traverse across one row and drop to the next to traverse back across. However, there are two things that would highly complicate matters. To continue after it traverses the last row, something would need to be incorporated; and placing the wombat randomly at an even or odd row will produce different conditions. Some things that would need to be kept track of are (1) if the last move was a vertical move or not (2) whether the wombat is panning down or up the rows (3) whether we are in th

The use of 'wait(3)' will cause the whole scenario to essentially pause for the duration of the waiting time, which I doubt seriously is what you want. What you need to do is add a counter to count the act cycle;, and every so many cycles, change the image; and after so many more cycles, change the image back and reset the counter.