String Concatenation Operator +
If only one operand expression is of type String, then string conversion
is performed on the other operand to produce a string at run time. If both are
of type char, then string conversion is performed on both operands to produce
strings at run time. The result is a reference to a newly created
String
object that is the concatenation of the two
operand strings. The characters of the left-hand operand precede the characters
of the right-hand operand in the newly created string.