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  1. PO
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    <p>The easiest way to do this is with an <code>ArrayList&lt;char[]&gt;</code>. All you have to do is add a new <code>char[]</code> for each new line read:</p> <pre><code>ArrayList&lt;char[]&gt; chars = new ArrayList&lt;&gt;(); while (inputFile.hasNext()){ chars.add(inputFile.nextLine().toCharArray()); } char[][] array = chars.toArray(new char[chars.size()][]); </code></pre> <p>An <code>ArrayList</code> is basically an array of changeable size. This code takes each line in the file, turns it into a <code>char[]</code>, then adds it to the <code>ArrayList</code>. At the end, it converts the <code>ArrayList&lt;char[]&gt;</code> into a <code>char[][]</code>.</p> <p>If you can't or don't want to use <code>ArrayList</code>, you could always do this:</p> <pre><code>char[][] array = new char[1][]; int a = 0; while(inputFile.hasNext()){ //read line and convert to char[]; store it. array[a] = inputFile.nextLine().toCharArray(); //if there are more lines, increment the size of the array. if (inputFile.hasNext()){ //create a clone array of the same length. char[][] clone = new char[array.length][]; //copy elements from the array to the clone. Note that this can be //done by index with a for loop System.arraycopy(array, 0, clone, 0, array.length); //make array a new array with an extra char[] array = new char[array.length + 1][]; //copy elements back. System.arraycopy(clone, 0, array, 0, clone.length); a++; } } </code></pre> <p>If you know the dimensions of the array beforehand:</p> <pre><code>char[][] array = new char[dimension_1][]; int a = 0; while (inputFile.hasNext()){ array[a] = inputFile.nextLine().toCharArray(); a++; //don't need to check if we need to add a new char[] } </code></pre> <hr> <p>In response to comment:</p> <p>We know that a <code>char[][]</code> cannot be printed with <code>Arrays.toString()</code> (if we want the contents) because we will get a lot of <code>char[].toString()</code>. However, a <code>char[][]</code> can be printed with one of the following methods:</p> <pre><code>public static String toString(char[][] array){ String toReturn = "[\n"; for (char[] cArray: array){ for (char c: cArray){ toReturn += c + ","; } toReturn += "\n"; } return toReturn + "]"; } </code></pre> <p>I personally prefer this one (requires <code>import java.util.Arrays</code>):</p> <pre><code>public static String toString(char[][] array){ String toReturn = "[\n"; for (char[] cArray: array){ toReturn += Arrays.toString(cArray) + "\n"; } return toReturn + "]"; } </code></pre>
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    1. PO2d char array from a file
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    1. USJustin
    1. USJustin
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    1. COI am trying to use the first method you suggested with the arrayList. In order to print out the newly created 2D array will I just have to use the usual for loops to go through each row and column.
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      1. USCorey Crawford
    2. COYes. Or you could make a custom method (see post)
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      1. USJustin
 

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