@@ -257,7 +257,52 @@ __different__ from the type of literal/object it's holding/referring, you may re
257257Casting can be done by the compiler _ (implicit cast)_ or by you _ (explicit cast)_ . Typically, an implicit cast happens
258258when you're doing a __ widening conversion__ , in other words, putting a smaller thing (say, a byte) into a bigger container
259259(such as an int). But when you try to put a large value into a small container (referred to as __ narrowing__ ), you should
260- do an explicit cast, where you tell the compiler that you're aware of the danger and accept full responsibility.
260+ do an explicit cast, where you tell the compiler that you're aware of the danger and accept full responsibility. Let's
261+ for example consider the below program:
262+ 263+ {% highlight java linenos %}
264+ class Casting {
265+ public static void main(String [ ] args) {
266+ long a = 100; // literal '100' is implicitly an 'int'
267+ //but the compiler does an implicit cast
268+ int b = (int) 10.23; // literal '10.23' is implicitly a 'double'
269+ // so we require an explicit cast
270+ int x = 3957.229; // illegal, can't store a large value in a
271+ // small container without explicit cast
272+ }
273+ }
274+ {% endhighlight %}
275+ 276+ There is another rule which you must be aware of, i.e, __ the result of an expression involving anything int-sized or
277+ smaller is always an ` int ` __ . Check this out:
278+ 279+ {% highlight java %}
280+ byte a = 3; // No problem, 3 fits in a byte
281+ byte b = 8; // No problem, 8 fits in a byte
282+ byte c = a + b; // Should be no problem, sum of the two bytes
283+ // fits in a byte
284+ {% endhighlight %}
285+ 286+ The last line won't compile! You'll get an error like this:
287+ 288+ {% highlight java %}
289+ TestBytes.java:5: possible loss of precision
290+ found : int
291+ required: byte
292+ byte c = a + b;
293+ ^
294+ {% endhighlight %}
295+ 296+ Doing an explicit cast like:
297+ 298+ {% highlight java %}
299+ byte c = (byte) (a + b);
300+ {% endhighlight %}
301+ 302+ solves the issue.
303+ 304+ #### What happens when you cast a large value to store it in a small container
305+ 261306
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