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POOdd Java String[] issue, contains value but acts like null when inserting into List<String[]>
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  1. POOdd Java String[] issue, contains value but acts like null when inserting into List<String[]>
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    copied!<p>I am having an issue with a String array and trying to add it to a list (List). Below is the code that is used and creating the issue.</p> <p>The program fails on the first run through of the loop and I have verified the input which comes from a CSV using OpenCSV.</p> <pre><code>List&lt;String[]&gt; output = null; String[] temp; for(int i = 0; i &lt; 13; i++) { temp = reader.readNext(); //read next line into temp System.out.println(temp[0]+temp[1]+temp[2]); //temp output temp[2] = String.valueOf((values[i])/100); //assign new value System.out.println(temp[0]+temp[1]+temp[2]); //temp output output.add(temp); } </code></pre> <p>When this code runs the output is.</p> <pre><code>VANCBULLET0.311 VANCBULLET0.308 Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException at Main.updateCSV(Main.java:951) at Main.start(Main.java:863) at Main.access$23(Main.java:853) at Main$23.actionPerformed(Main.java:520) at javax.swing.AbstractButton.fireActionPerformed(Unknown Source) at javax.swing.AbstractButton$Handler.actionPerformed(Unknown Source) at javax.swing.DefaultButtonModel.fireActionPerformed(Unknown Source) at javax.swing.DefaultButtonModel.setPressed(Unknown Source) </code></pre> <p>The first two lines are correct and are split up like: temp[0] temp[1] temp[2] VANC BULLET 0.311 VANC BULLET 0.308</p> <p>The issue is (like the error reads) at: </p> <pre><code>output.add(temp); </code></pre> <p>The documentation reads:</p> <pre><code>NullPointerException - if the specified element is null and this list does not permit null elements </code></pre> <p>but as you can see from my output (the second line) the array "temp" is not null, it contains "VANC BULLET 0.308" in each element respectively.</p> <p>I'm stumped. Does anyone have an idea or see something I have failed to see?</p> <p>Thanks</p>
 

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