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PODo the Java Integer and Double objects have unnecessary overhead?
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copied!<p>I am working with Java 1.3, so it does not support generics. I came up with a shady work around. I want to know if the Integer and Double objects have an unnecessary overhead; I guess what I am asking is: do Integers take up same amount of space as an int? Same question for Double and doubles.</p> <p>From what I know, the array of Objects holds an array of 32 bit integers that actually hold the address to the Object in memory independent of the array. But when I explicitly make an array of primitives like I did here, the outcome would be bad. Because, AFAIK, an array of primitives actually are an array of the data, not the pointers to the data. Or am I just assuming too much from C++? </p> <p>So, if the Array in DataPackage actually does hold pointers instead of the primitives, I am good to go. But if they hold the primitives themselves, accessing the data will be a problem since a double is 64 bits of data, but a pointer to that is still 32 bits. </p> <pre><code>/** * * * @todo Comment all the code. * @author Davidthefat * @version 1.0 */ public class DataPackage { private String dataType; private Object data; /** * * @param type * @param numOfItems */ public DataPackage(String type, int numOfItems) { dataType = type; if (type.equals("Wheels")) { data = new int[numOfItems * 2]; } if (type.equals("Arms")) { data = new int[numOfItems * 1]; } if (type.equals("Joysticks")) { data = new double[numOfItems * 2]; } if (type.equals("Buttons")) { data = new boolean[numOfItems * 4]; } } /** * * @param t1 */ public void update(Object t1) { data = t1; } /** * * @return */ public Object getData() { return data; } /** * * @return */ public String toString() { return "This contains " + dataType; } } </code></pre> <p>To access that data, I cast the array of Objects as an array of Integers then call the intValue() function: temp is an array of ints. I must also put that getData in input just returns a DataPackage.</p> <pre><code>temp[0] = ((Integer[])input.getData("Wheels").getData())[0].intValue(); </code></pre> <p>I can't just run this code right now since this is for the FRC Robot at my school, and school's out. </p>

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