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SCJP6 regex issue

\d* matches 0 or more digits. So, it will even match empty string before every character and after the last character. First before index 0, then before index 1, and so on. So, for string ab34ef, it matches following groups: Index Group 0 “” (Before a) 1 “” (Before b) 2 34 (Matches more than … Read more

Why can not I add two bytes and get an int and I can add two final bytes get a byte?

From the JLS 5.2 Assignment Conversion In addition, if the expression is a constant expression (§15.28) of type byte, short, char, or int: – A narrowing primitive conversion may be used if the type of the variable is byte, short, or char, and the value of the constant expression is representable in the type of … Read more