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Thread: variables and efficiency

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    Default variables and efficiency

    If I'm going to need to use (say) the size of an array several times then is it more efficient to declare a new variable and put the size of the array into it or is it more efficent to use .size to look it up again each time? (Sorry if this is a very niave question - I'm very new to this). Thanks in advance,
    Catkinq


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    Default Re: variables and efficiency

    I believe all of Java's Collections API classes store the size of the collection inside of a variable, so for all practical cases the efficiency of both methods are pretty much the same.

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    Default Re: variables and efficiency

    Well if you're actually using an array such as String[] then you can use the length variable whenever you wish, its a normal variable after all and not a method call.

    And if you decide to use an ArrayList and call the size() method all that does is return the instance member int size. So like helloworld says, no biggie really. Use whatever you wish without storing it in a new variable, in fact, storing it in a new variable might take more time

    // Json

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    Smile Re: variables and efficiency

    thank you for the replies

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