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Index › Programming Questions & Help › Programs › About data structures

JScriptChan Junior Member Offline Posts: 57	About data structures Jul 2nd, 2009, 3:44am   Hello all,how to build a Queue in PDE?Or would you recommend some references about building data structures in PDE?Thank you.
	more joy,more practice

eskimoblood Senior Member Offline Posts: 341	Re: About data structures Reply #1 - Jul 2nd, 2009, 4:55am   As processing is 100% JAVA they are still there: http://java.sun.com/j2se/1.5.0/docs/api/java/util/Queue.html
	Andreas Köberle {eskimoblood}

alvaro Junior Member Offline Posts: 85 Berlin

Re: About data structures Reply #2 - Jul 2nd, 2009, 4:57am   Hi, A basic first-in-first-out queue of numbers to get you started Code: // Create a Queue LinkedList queue = new LinkedList(); // Put some numbers in it // Each number is added at the end of the Queue. queue.offer(1); queue.offer(2); queue.offer(3); // get the first element, as an int int element = (Integer) queue.pop(); println(element); as for data structures: they are called Objects. See here http://processing.org/learning/objects/ alvaro

alvaro Junior Member Offline Posts: 85 Berlin	Re: About data structures Reply #3 - Jul 2nd, 2009, 5:09am   hey eskimo wassup? anyways LinkedList implements Queue, and is afaic the easiest to get started with, but of course you may choose another implementation, depending on what you want to do (multithreading, fixed number of elements, alternative ordering)

JScriptChan Junior Member Offline Posts: 57	yeah Reply #4 - Jul 3rd, 2009, 4:22am   Thank you!It works! And how about the declaration of "Queue q;"?It seems also valid,but how to initialize it,say,give its initial value,in the form like "ArrayList al=new ArrayList()"? Thank you for reply.
	more joy,more practice

alvaro Junior Member Offline Posts: 85 Berlin	Re: About data structures Reply #5 - Jul 3rd, 2009, 5:02am   Queue is an Interface. It's like a template for a family of classes. But you can't initialise an interface, you have to choose one of the implementing classes. Java comes with a number of classes that implement Queue, but LinkedList is the most general purpose one I think.