I've had a few people tell me that things like this are super lazy:
int val = 5;
System.out.println("" + val);
String myStr = "" + val;
Why is this better than String.valueOf(val)? Isn't it doing the exact same thing under the hood?
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4This has already been answered before, http://stackoverflow.com/questions/7752347/string-valueof-vs-concatenation-with-empty-string – Hank Jan 27 '16 at 23:46
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1It isn't better than `String.valueOf(int)`; it's worse and it's lazy. – Elliott Frisch Jan 27 '16 at 23:47
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It's not really "better", just shorter, making it easier to read and type. There is (virtually) no ther difference, even though a real purist might, probably, say, this is actually worse, because (at least, in the absence of optimization), this creates an intermediate StringBuilder object, that is then appended a character before being converted into a String, so, this may be spending more ticks, than .valueOf.
Dima
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From JLS:
An implementation may choose to perform conversion and concatenation in one step to avoid creating and then discarding an intermediate String object. To increase the performance of repeated string concatenation, a Java compiler may use the StringBuffer class or a similar technique to reduce the number of intermediate String objects that are created by evaluation of an expression.
For primitive types, an implementation may also optimize away the creation of a wrapper object by converting directly from a primitive type to a string.
