#37 Boolean objects always true

[Sebastián Gurin]

Because any Boolean instance is an object (not a boolean) when logically evaluated it is always true. The following program try to prove.

public class BooleanBug {
public static void main(String[] args) {
Boolean b = new Boolean(false);
if(!b) {
System.out.println("OK");
}
else {
System.out.println("BUG!");
}
}
}

the correct if expression would be:

if(!b.booleanValue()) {...

I'm not really sure how this can be fixed, perhaps doing special treatment when a Boolean object is evaluated...

[Zhou Renjian]

It is a bug in the compiler. Compiler should unbox the expression "!b" into "!b.booleanValue()".

"if (b) {}" is compiled correctly into "if (b.booleanValue()) {}".

The bug lies in ASTKeywordVisitor, line 830:
public boolean visit(PrefixExpression node) {
and ASTScriptVisitor, line 1648:
public boolean visit(SimpleName node) {
There should be some lines checking "exp.resolveUnboxing()", similar as in ASTTigerVisitor line 62.