What is the primary reason Java does not support multiple inheritance?

Java does not support multiple inheritance primarily to avoid ambiguity and complexity. When a class can inherit from multiple classes, it can lead to situations where the compiler cannot determine which superclass method to use. This is particularly problematic when multiple superclasses have methods with the same name and signature, a situation commonly referred to as the "Diamond Problem." To maintain clarity in the inheritance hierarchy and ensure that code is easier to understand and maintain, Java explicitly avoids multiple inheritance of classes.

While simplifying code, enhancing performance, and encouraging the use of interfaces are all valid concerns in object-oriented design, they are not the primary reasons for Java's design decision against multiple inheritance. Instead, the language design focuses specifically on the potential for ambiguity and complexity arising from such a feature. By using interfaces, Java provides a way to achieve multiple inheritance of type without the complications that come with inheriting implementation from multiple classes, allowing for a cleaner and more manageable code structure.