Adding a jar to an eclipse project is normally really easy. I came home from school today after adding the AP Computer Science gridworld jar. I always have to add external libraries twice because at school we have OSX and at home I have Windows, so the file paths don’t match up.
So after trying to [...]
My Computer Science discovers interesting things sometimes. Recently we were doing a little practice with Exceptions and try-catch blocks. One of our projects was to handle division by zero and not crash the program. That sounds like a ordinary project, but as it turns out, it was a more surprising than anyone would have ever [...]
Back to the old Java Grid Stone this week, but hey, it’s fun anyway. This time, it’s Matrix Multiplication. I failed to find sufficiently explained information about this horrid excuse for Java, so I want to help everyone else out.
In java, you’re typically dealing with matrices of int or double. The code I provide below [...]
In Greenfoot, you can use the MouseInfo class to find out where the mouse is. I’ve talked about making actors draggable, but sometimes you don’t want to use the Mouse Location in an actor, but possibly inside the world instead.
Take a look at the following code:
public static int MouseX = 0, [...]
Today I was trying to draw a simple rectangle in Greenfoot. Images can dynamically made with the GreenfootImage class. When I drew my rectangle today, it was missing its bottom and right sides!
My initial code looked something like this:
// code inside of Actor called Thing
public Thing() {
[...]
If you have a 64-bit operating system, you might consider taking advantage of the 64-bit version of Java and Eclipse. Once you have installed the 64-bit Java, you’ll probably go to Eclipse.org to grab a copy of your favorite IDE. But it work right.
You’ll need a 64-bit version of Eclipse to work with your 64-bit [...]
Our favorite development tool, Eclipse, makes it slightly confusing to read files properly inside of a Java program.
To start with, I make a file as anyone would, just a quick right click in the Project Tree, then New and finally to File as in a blank file.
One would assume that a non-java would exist [...]
I encountered this error today from copying and pasting a code snippet that was from one of our PDF textbooks.
illegal character /160
After making sure that our brackets matched, methods weren’t variables, variables weren’t methods, we didn’t know what was going on. Everything looked good and clean. So we decided to do the unthinkable: we retyped [...]
Sometimes you need to use an ArrayList. It can be when you’re lazy or when you want flexibility. Eventually, you’ll want to get away from the ArrayList and use your stores objects as standard object array. Doing this isn’t very complicated but it is slightly hidden.
We’re going to pretend for a moment that we have [...]