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Question from mock exam

Punitha krishna

Joined: Nov 22, 2000
Posts: 16
Which assignments are legal?
Select all valid answers.
a. long test = 012;
b. float f = -412;
c. int other = (int)true;
d. double d = 0x12345678;
e. short s = 10;
The correct answers are a,b,d,e.
I don't understand how b and d are correct.
Milind Deodhar
Ranch Hand

Joined: Dec 06, 2000
Posts: 32
b is correct because it is a int value and can be put in float without casting. (even if it is negative).
Second is correct, because I think double can hold the biggest value and no cast is required to put any primitive into double
(only cannot put boolean value)
Punitha krishna

Joined: Nov 22, 2000
Posts: 16
Thanks It is clear now. I guess I didn't read the question properly.
David Roberts
Ranch Hand

Joined: Nov 03, 2000
Posts: 142
You probably already know this but:
float f = -412; //Would Pass (int fits in float)
float f = -412.0; //Would fail (double doesn't fit in float)
float f = -412.0f; //Would pass (explicitly stating float)
float f = (float)-412.0; //Would pass (Cast)
- David

David Roberts - SCJP2,MCP
Vladimir Kositsky
Ranch Hand

Joined: Nov 03, 2000
Posts: 116
Java allows conversion between integer values( byte, short, int, long) and floating point values( float, double).
Both of questions are examples of "automatic" widening conversion, when value of "narrower" type is converted into "wider" type.
Vice versa explicit casting needed.
I agree. Here's the link: http://aspose.com/file-tools
subject: Question from mock exam