Strange java behaviour

[priyom]

Please got through the following code snippet.

class NanTest {

public static void main ( String args [ ] ) {
int intX = 10 ; // line 1
float floatX = 10 ; // line 2
double doubleX = floatX / 0 ; // line 3
double doubleY = intX / 0 ; // line 4
System . out . println ( doubleX == doubleY ) ; // line 5
}
}

It throws exception on line 4 but not on line 3.
Could anyone please explain this.

 

[Gordon Beaton]

It throws exception on line 4 but not on line 3.
Could anyone please explain this.

Did you try to display the value of doubleX?

Floating point division never results in an exception. In this case,
you get Infinity.

Integer division by 0 results in an exception.

See JLS 15.17.2:
http://java.sun.com/docs/books/jls/third_edition/html/expressions.html#45471

/gordon

 

[M.J. Dance]

Please got through the following code snippet.

class NanTest {

public static void main ( String args [ ] ) {
int intX = 10 ; // line 1
float floatX = 10 ; // line 2
double doubleX = floatX / 0 ; // line 3
double doubleY = intX / 0 ; // line 4
System . out . println ( doubleX == doubleY ) ; // line 5
}
}

It throws exception on line 4 but not on line 3.
Could anyone please explain this.

http://java.sun.com/developer/TechTips/1998/tt0722.html#tip2

 

[Patricia Shanahan]

Please got through the following code snippet.

class NanTest {

public static void main ( String args [ ] ) {
int intX = 10 ; // line 1
float floatX = 10 ; // line 2
double doubleX = floatX / 0 ; // line 3
double doubleY = intX / 0 ; // line 4
System . out . println ( doubleX == doubleY ) ; // line 5
}
}

It throws exception on line 4 but not on line 3.
Could anyone please explain this.

Line 4 is an int division by zero, and there is no way to represent the
result as an int, so it throws an exception.

Line 3 is a float division by zero, and there is a value,
Float.POSITIVE_INFINITY, that represents the result of dividing a
positive float by a zero float.

Patricia

 

[Lew]

class NanTest {

public static void main ( String args [ ] ) {
int intX = 10 ; // line 1
float floatX = 10 ; // line 2
double doubleX = floatX / 0 ; // line 3
double doubleY = intX / 0 ; // line 4
System . out . println ( doubleX == doubleY ) ; // line 5
}
}

It throws exception on line 4 but not on line 3.
Could anyone please explain this.

Line 4 is an int division by zero, and there is no way to represent the
result as an int, so it throws an exception.

Line 3 is a float division by zero, and there is a value,
Float.POSITIVE_INFINITY, that represents the result of dividing a
positive float by a zero float.

http://docs-pdf.sun.com/800-7895/800-7895.pdf
and
http://docs.sun.com/source/806-3568/ncg_goldberg.html

The latter is the HTML form of the former.

- Lew