Explicit Conversion?

the book that im reading says

Quote:

---

"" + <number>

---

<< "this is the easy way to convert a numerical value to STRING"?

assuiming that the variable number is an integer.

is it what they called explicit conversion?

No, that's an implicit conversion (technically, it's not a cast at all in this case, see the reason below). An explicit conversion is one you specifically tell Java to do:

Code :

---

int a = 5;
String b = (String) a; // explicit

---

Note: because of the funny implementation of Strings in Java, this cast here will fail (the compiler will complain).

Reason: Java normally doesn't allow operator overloading. However, the + has been over-ridden for Strings to mean concatenation. The String concatenation method is able to take any primitive data type and convert it to a string equivalent value. However, because String is not a primitive data type, you cannot explicitly tell Java you want to cast an int to a String and vise versa.

oh sorry thats what im trying to imply, i just misinterpret the difference between "implicit" and " explicit" conversion..

yah yah, thats what i want to ask.. "implicit" haha,, :) ,

i thought this was "explicit"
[CODE] "" + number[\CODE]
so this is the "implicit"

anyway, so thats how the java manipulate strings, and tnx for the knowledge about "concatenating", every time i concatenate a primitive type i thougt that it still have value (i mean its data type) as it is when you declared it..

like the code above, i thought that the variable "number" is still the data type as when you declared it , but when you concatenate it with strings. it will become string too(and that is "implicit") hehe, thought it was "explicit" ,

i just understood it reversely..

concatenation doesn't really apply to primitives... It means "adding to the end of".

So:

Code :

---

"Hello" + " world"

---

is the same as

Code :

---

"Hello".concat(" world");

---