Why don’t Java’s +=, -=, *=, /= compound assignment operators require casting long to int?

by

As always with these questions, the JLS holds the answer. In this case §15.26.2 Compound Assignment Operators. An extract:

A compound assignment expression of the form E1 op= E2 is equivalent to E1 = (T)((E1) op (E2)), where T is the type of E1, except that E1 is evaluated only once.

An example cited from §15.26.2

[…] the following code is correct:

short x = 3;
x += 4.6;

and results in x having the value 7 because it is equivalent to:

short x = 3;
x = (short)(x + 4.6);

In other words, your assumption is correct.

More Related Contents:

  1. Why don’t Java’s +=, -=, *=, /= compound assignment operators require casting?
  2. Why does this go into an infinite loop?
  3. Java Operators : |= bitwise OR and assign example [duplicate]
  4. Integer division: How do you produce a double?
  5. What is x after “x = x++”?
  6. What is the difference between & and && in Java?
  7. explicit casting from super class to subclass
  8. Is it possible to pass arithmetic operators to a method in java?
  9. Creating a “logical exclusive or” operator in Java
  10. Pipe (|) operator in Java
  11. What does an assignment expression evaluate to in Java?
  12. Convert boolean to int in Java
  13. Difference between & and && in Java? [duplicate]
  14. Java: What does ~ mean
  15. Why is assignment to ‘this’ not allowed in java?
  16. How does Java Object casting work behind the scene? [duplicate]
  17. How to cast from List to double[] in Java?
  18. Why cannot cast Integer to String in java?
  19. XOR operation with two strings in java
  20. Java: Casting from List to List when B implements A?
  21. Explicit casting from super-class to sub-class
  22. Java: What’s the difference between autoboxing and casting?
  23. Difference between a += 10 and a = a + 10 in java? [duplicate]
  24. com.google.gson.internal.LinkedTreeMap cannot be cast to my class [duplicate]
  25. Java casting order
  26. Difference between casting to String and String.valueOf
  27. Type safety: Unchecked cast from Object
  28. Java Casting Interface to Class
  29. Java casting “.class”-operator used on a generic type, e.g. List, to “Class
  30. Comparing float and double primitives in Java

Leave a Comment