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PONull Pointer Exception in JUnit test
 

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  1. PONull Pointer Exception in JUnit test
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    <p>Whenever I try to test my code with JUnit, I receive a NullPointerException - even though I don't get that exception when I run the actual program. The line that gives me the exception is:</p> <pre><code>assertEquals(0.0, TweetClassification.tweetType[TweetClassification.SIGNIF_OTHER].likelihoodA); </code></pre> <p>The beginning of the TweetClassification class it's testing is as follows:</p> <pre><code>public class TweetClassification { // CONSTANTS ============================================= public static final int TCNUMBER = 5; // number of TweetCategories (including the null category) // using constants to indicate the names of the TweetCategories, so that they could be renumbered public static final int NULLTWEET = 0; public static final int SIGNIF_OTHER = 1; public static final int FRIENDS = 2; public static final int WORK = 3; public static final int FOOD = 4; public static final TweetCategory[] tweetType = new TweetCategory[TCNUMBER]; ... </code></pre> <p>(TweetCategory is another class that is defined separately within the package.) So I realize that this code initializes the array but not its members, and that's probably why I'm getting the exception(?) But the thing is, I do initialize the members of the array within the main method of TweetClassification, as follows:</p> <pre><code>for (int i=0; i&lt;TCNUMBER; i++) { tweetType[i] = new TweetCategory(); } </code></pre> <p>But if I try to move this for loop outside the main method with the constants I get a syntax error - I presume you're not supposed to use a for loop outside of a method. So I'm not sure how to initialize the class properly for JUnit to work - either I do it outside the main method and get a syntax error, or I do it inside the main method and get a NullPointerException. Any ideas?</p>
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    1. USPeter O.
    1. USDisplaced Hoser
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    1. COPlease show the code inside the `main` method too.
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