Is there any difference between a=a+b and a+=b?

+= The operator will perform implicit automatic type conversion , here a+=b Implicitly cast the result type of the add operation to the type of holding the result , and

a=a+b No automatic type conversion . Such as ：

Is there any error in the following code , How to change if there is any ？

Erroneous .short The type is automatically promoted to int type , in other words s1+1 The result is int type , and s1 yes short

type , The compiler will report an error .

Write it correctly ：

Integer i = 6;

Integer j = 6;

System.out.println(i==j);

public static Integer valueOf(int i) {

if (i >= IntegerCache.low && i <= IntegerCache.high)

return IntegerCache.cache[i + (-IntegerCache.low)];

return new Integer(i);

}

byte a = 127;

byte b = 127;

b = a + b; // Report compilation error :cannot convert from int to byte

b += a;

short s1= 1;

s1 = s1 + 1;

short s1= 1;

s1 += 1;

+= The operator will force the expression result on the right to match the data type on the left , So that's right