Why don't Java's +=, -=, *=, /= compound assignment operators require casting?

Why don't Java's +=, -=, *=, /= compound assignment operators require casting?

java casting operators variable-assignment assignment-operator

java

Safely casting long to int in Java

java casting

java

Cast Double to Integer in Java

java casting

java

Convert boolean to int in Java

java casting boolean int

java

Cast Int to enum in Java

java casting enums ordinal

java

Convert String to double in Java

java string casting double type-conversion

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Integer division: How do you produce a double?

java casting integer-division

java

How do you cast a List of supertypes to a List of subtypes?

java list generics collections casting

java

Downcasting in Java

java casting

java

How to insert a character in a string at a certain position?

java string casting

java

explicit casting from super class to subclass

java casting classcastexception

java

Cast Object to Generic Type for returning

java generics casting

java

Most efficient way to cast List<SubClass> to List<BaseClass>

java inheritance casting

java

What is the difference between up-casting and down-casting with respect to class variable

java casting class-variables downcast upcasting

java

Converting BigDecimal to Integer

java integer casting bigdecimal

java