conditional operator in case expression

Name: laC46010 Date: 02/08/99



The following example shows that javac (ver. 1.1.x, 1.2fcs, 1.2.2) allows
usage of expressions which are not "constant expressions" as stated in JLS,
notwithstanding that the value of some expressions can be known at the compile
time.
In the following example a conditional expression with local variable is used
in switch statement. According to the JLS 15.27 a non-final variable can not be
used in constant expression:

"A compile-time constant expression is an expression denoting a value of
 primitive type or a String that is composed using only the following:

     Literals of primitive type and literals of type String
     Casts to primitive types and casts to type String
     The unary operators +, -, ~, and ! (but not ++ or --)
     The multiplicative operators *, /, and %
     The additive operators + and -
     The shift operators <<, >>, and >>>
     The relational operators <, <=, >, and >= (but not instanceof)
     The equality operators == and !=
     The bitwise and logical operators &, ^, and |
     The conditional-and operator && and the conditional-or operator ||
     The ternary conditional operator ? :
     Simple names that refer to final variables whose initializers are constant expressions
     Qualified names of the form TypeName . Identifier that refer to final variables
     whose initializers are constant expressions"


Test example and javac diagnostics follow:
-------------------------------------------------------
novo35% cat test.java
class test {
    test() {
        final boolean b = true;
        int i = 0;
        switch(0) {
        case b ? 0 : i:
        }
    }
}
novo35% java -version
java version "1.2.2"
Classic VM (build JDK-1.2.2-E, green threads, sunwjit)
novo35% javac test.java
novo35%
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