Java: Out with the Old, In with the New

Question

Java is nearing version 7. It occurs to me that there must be plenty of textbooks and training manuals kicking around that teach methods based on older versions of Java, whe

Answer 1

Formatted printing was introduced as late as in JDK 1.5. So instead of using:

String str = "test " + intValue + " test " + doubleValue;

or the equivalent using a StringBuilder,

one can use

String str = String.format("test %d test %lg", intValue, doubleValue);

The latter is much more readable, both from the string concatenation and the string builder versions. Still I find that people adopt this style very slowly. Log4j framework for example, doesn't use this, although I believe it would be greatly benefited to do so.