2013年12月12日星期四

Integer directly to the variable assignment and what is the difference with a new assignment ?

As stated , the result is the same.

import java.util.*;

public class Test
{
public static void main(String [] args)
{
         
        Integer x = 10;
        Integer y = new Integer(10);
        
        System.out.println(x);
        System.out.println(y);
}
}


------ Solution ------------------------------------ --------
a reference to a value that is Integer, is assigned a value . And an object reference , he is assigned an address .
------ Solution ---------------------------------------- ----
and direct assignment and new String String is a reason
new words wasted memory
------ Solution ------------------------------ --------------

public static void main(String[] args) {
Integer i1=10;
Integer i2=10;
Integer i3=new Integer(10);
Integer i4=128;
Integer i5=128;
System.out.println(i1==i2);//true
System.out.println(i1==i3);//false
System.out.println(i4==i5);//false
}
1st floor
do not understand anything , do not look
Integer x = 10 ;/ / automatic packing , if between -128 to 127 , the value of the constant presence of the pool ( 10 ) ;/ / object ordinary heap
Integer y = new Integer

------ Solution ------------------------------------ --------
first performed automatic packing operation, with the second one is the same, so the two are the same
------ Solution ------ --------------------------------------


+1
------ For reference only -------------------------------- -------
Thank you , 3rd floor, very intuitive and clear explanations .

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