C/C++ Pointers vs. Java References – What’s the Difference?

Some programming languages, including C and C++, support pointers. References are supported by several other languages, including C++, Java, Python, Ruby, Perl, and PHP. References and pointers allow one variable to offer access to another; on the surface, they appear to be quite similar. 

It’s sometimes difficult to see what distinguishes these various systems as they offer many of the same features. This article will explain in detail the distinction between pointers and references.

Java has references instead of pointers

Reference: A reference is a variable that points to another object and may be used as its alias.

Pointer: A pointer is a variable that carries a memory location to serve as an alias for the data that is kept there.

Therefore, a pointer is a reference, but not always the other way around. The word “pointer” is often exclusively used for programming languages that provide direct access to the memory location since pointers are a specific application of the idea of a reference.

Here are some essentials to know about pointers and references in Java and C/C++ contexts:

• Java Pointers (References) do not provide pointer arithmetic, but C/C++ does: The notion of pointers, which are variables that record memory addresses and may be changed arithmetically to refer to arbitrary addresses, is closely related to the term “pointer” in the C/C++ programming language. Pointers are only present in Java as a References implementation feature. A duplicate of the reference, referring to the same object as the calling function and enabling you to modify that object, is copied to the stack of a called function. However, the object that the calling function refers to cannot be altered.

• Java utilizes pointers indirectly even if it doesn’t allow pointers directly: Java manipulates references via pointers. However, these pointers are not accessible to outside users. Any processes that the language performs implicitly are NOT visible.

• Pointers can do calculations, but references can’t: Pointer arithmetic is essentially hazardous for gaining memory access, and Java’s robust security architecture forbids it as a precaution. Users cannot change pointers under any circumstances.

• Pointing objects: Adding or removing the address of a pointer in C allows us to point at objects. A reference in Java always refers to the same thing. Although you may change a variable’s reference, you cannot manipulate pointers in C in this way.

• Strongly typed references: Java has stricter controls over reference type than Cover pointer type. In C, you may cast an int to a char and then reinterpret the memory there. In Java, you can only decrypt the object at the other end of the reference as something that it already is, so reinterpretation is impossible (i.e., you can cast an object reference to a String reference only if the object pointed to is a String).

• Pointer manipulation can be risky: On the one hand, having user control over pointers might be advantageous and versatile, but it could also be dangerous. They might be a significant source of issues since, if utilized improperly, they can quickly invalidate presumptions upon which your code is based. And misusing them is pretty simple.

As a result, Java does not have pointers (in the C/C++ sense) since general-purpose OOP programming does not require them. Additionally, introducing pointers to Java would reduce its security and resilience and increase its complexity.