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Null should not be returned from a "Boolean" method.
toString(boolean b) returns a String object representing the specified boolean. If the specified boolean is true, then the string "true" will be returned, otherwise the string "false" will be returned.
Unfortunately the compiler is not capable of deducing that the statement boolean var1=(var=null); would always lead to the invalid assignment boolean var1=null .
Well, Boolean is the wrapper for the primitive boolean. This introduces a third possible status for a boolean variable: As objects are nullable, Booleans are nullable too. So… a Boolean can be true, false… or null.
Boolean variable cannot have a value of null because it is a non-nullable value type. Answer is 1 & 5. 1) We can assign the any type value to the variable of object data type.
The (expression) will evaluate to true if it can be converted to bool. "hello" is a string literal which evaluates to a pointer and since it's different than 0 it will result in true. A null pointer would return false.
Can Boolean.valueOf(String) ever return null? From what I can see in the java docs, the docs only specify when it returns true. Is false always returned otherwise, or can null be returned? I have not been able to get it to return null in the tests I have done, but I would like to be sure.
Essentially, I want to know if the following code is safe from a NullPointerException:
boolean b = Boolean.valueOf(...);
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