by Daniel » Sat, 28 Jun 2008 01:25:26 GMT
Hi All, I did not develop mobile project before, and now I must to develop an Android project. example, J2ME doesn't contain HashMap class. I think it is under the consideration of performing. I just want to know if I use some classes, which aren't included in J2ME, can it have great influence on performin. Thanks Daniel --~--~---------~--~----~------------~-------~--~----~
by Romain Guy » Sat, 28 Jun 2008 01:37:52 GMT
Hi, HashMap is a very useful class that performs well. Without knowing how you intend to use this class, we cannot really tell you whether it will impact performance or not. However, HashMap can be used without any problem in a large number of situations without impacting performance. The only situation in which you might want to avoid HashMap is if you need to store primitive types (int, long, short, etc.) inside, either as key or value. This will force you to use autoboxing which will create new objects (Integer, Long, Short, etc.). In such a situation, you might want to use a SparseArray instead. -- Romain Guy www.curious-creature.org --~--~---------~--~----~------------~-------~--~----~
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