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copied!<p>You might want to also specify an amount by which to count. Default value would be <code>1</code>.</p> <p>You can get around some of this by using the <code>Number</code> method <code>.doubleValue()</code> and doing double arithmetic.</p> <p>Here is one of the methods converted to use this idea.</p> <pre><code>public void decrement(double valToDecrementBy) { double work = this.value.doubleValue(); work -= valToDecrementBy; // should use some value related to incrementing amount if ((this.value.doubleValue() - this.lowValue.doubleValue()) < 0.1D) { work = ((this.value.doubleValue() + this.highValue.doubleValue() + 1) - this.lowValue.doubleValue()); } // ... no way to put it back } </code></pre> <p>But, there is still no way to put the value back that's clean and easy. Since 'Number' only has a few commonly used non-abstract subclasses, you could do some ugly <code>instanceof</code> stuff to store the value back. It would look something like this:</p> <pre><code>if (theValue instanceof Double) { // depends on it having a non-null value prior theValue = (T)(new Double(work)); } </code></pre> <p>Or you could convert the starting values to <code>double</code> when you start and just work with doubles.</p> <pre><code>private double value; private double lowValue; private double highValue; public GenericRolloverCounter(T l_startValue, T l_highValue) { this.lowValue = l_startValue.doubleValue(); this.highValue = l_highValue.doubleValue(); this.value = l_startValue.doubleValue(); } </code></pre> <p>That does introduce the issues of incrementing floating point values and the rounding/evaluation problem there.</p> <p>Oh ... and your <code>toString()</code> should be:</p> <pre><code>return value.toString(); </code></pre> <p>To use the native <code>toString()</code> method on the <code>T</code> class.</p> <p>@Crusher's comments suggest another way to do it. Map everything to 'int' and keep a multiplier. Here's some bits of code to show what I mean. (Thanks Crusher)</p> <pre><code>private int value; private int lowValue; private int highValue; private double incr; public GenericRolloverCounter(T l_startValue, T l_highValue, T incrementAmount) { double incr = incrementAmount.doubleValue(); this.lowValue = Math.round(l_startValue.doubleValue() / incr); this.highValue = Math.round(l_highValue.doubleValue() / incr); this.value = Math.round(l_startValue.doubleValue() / incr); } public void increment(int valToIncrementBy) { this.value += valToIncrementBy; if (this.value > this.highValue) { this.value = (this.lowValue + (this.value - (this.highValue + 1))); } } @Override public String toString() { return String.valueOf(incr * this.value); } </code></pre>

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