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Wrappers -

 
Masood Alam
Greenhorn
Posts: 8
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Greetings,

In the below code //Line 1 results in "true" and the //Line results in "false"

Could someone please explain... its seems to be similar to "String Pool"

/**************************CODE*************************************/

class TestIntegers{

public static void main(String[] args){

Byte b1= 5;
Byte b2 = 5;
Byte b3 = new Byte("10");
Byte b4 = new Byte("10");
System.out.println("First Style " + (b1 == b2)); //Line 1
System.out.println("Second Style " + (b3 == b4)); // Line 2

}

}
 
Ulf Dittmer
Rancher
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b1 and b2 are created using auto-boxing, which doesn't employ "new Byte(...)", but rather Byte.valueOf(...). The difference is that valueOf doesn't create a new object - it reuses an existing one. Hence the two objects are identical.
 
Jared Folino
Greenhorn
Posts: 25
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Just remember that it is only for wrappers between -128 and 127
 
kaushik vira
Ranch Hand
Posts: 102
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hello Masood,

I think you are using jdk 1.5 for you compiling code.. try this code in 1.4 it wan`t allow you to compile this code...

what is going on here due to new feature added in 1.5 is auto bouncing.. so go thorough it..

And remember you are preparing for scjp 1.4 or scjp 1.5.. your ans vary based on this..

in 1.4 it give you compilation error...
in 1.5 it give wan`t give you any error and will work fine...
 
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