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copied!<pre><code>class ArrayComparator implements Comparator<Comparable[]> { private final int columnToSort; private final boolean ascending; public ArrayComparator(int columnToSort, boolean ascending) { this.columnToSort = columnToSort; this.ascending = ascending; } public int compare(Comparable[] c1, Comparable[] c2) { int cmp = c1[columnToSort].compareTo(c2[columnToSort]); return ascending ? cmp : -cmp; } } </code></pre> <p>This way you can handle any type of data in those arrays (as long as they're Comparable) and you can sort any column in ascending or descending order.</p> <pre><code>String[][] data = getData(); Arrays.sort(data, new ArrayComparator(0, true)); </code></pre> <p>PS: make sure you check for <code>ArrayIndexOutOfBounds</code> and others.</p> <p>EDIT: The above solution would only be helpful if you are able to actually store a <code>java.util.Date</code> in the first column <em>or if your date format allows you to use plain String comparison for those values</em>. Otherwise, you need to convert that String to a Date, and you can achieve that using a callback interface (as a general solution). Here's an enhanced version:</p> <pre><code>class ArrayComparator implements Comparator<Object[]> { private static Converter DEFAULT_CONVERTER = new Converter() { @Override public Comparable convert(Object o) { // simply assume the object is Comparable return (Comparable) o; } }; private final int columnToSort; private final boolean ascending; private final Converter converter; public ArrayComparator(int columnToSort, boolean ascending) { this(columnToSort, ascending, DEFAULT_CONVERTER); } public ArrayComparator(int columnToSort, boolean ascending, Converter converter) { this.columnToSort = columnToSort; this.ascending = ascending; this.converter = converter; } public int compare(Object[] o1, Object[] o2) { Comparable c1 = converter.convert(o1[columnToSort]); Comparable c2 = converter.convert(o2[columnToSort]); int cmp = c1.compareTo(c2); return ascending ? cmp : -cmp; } } interface Converter { Comparable convert(Object o); } class DateConverter implements Converter { private static final DateFormat df = new SimpleDateFormat("yyyy.MM.dd hh:mm"); @Override public Comparable convert(Object o) { try { return df.parse(o.toString()); } catch (ParseException e) { throw new IllegalArgumentException(e); } } } </code></pre> <p>And at this point, you can sort on your first column with:</p> <pre><code>Arrays.sort(data, new ArrayComparator(0, true, new DateConverter()); </code></pre> <p>I skipped the checks for nulls and other error handling issues.</p> <p><strong>I agree this is starting to look like a framework already. :)</strong></p> <p><em>Last (hopefully) edit: I only now realize that your date format allows you to use plain String comparison. If that is the case, you don't need the "enhanced version".</em></p>

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