The essence of a variable is a small memory unit, which stores the value of the variable; when a variable points to an object, the variable is called a reference variable. Java's reference variable is actually a pointer, which points to an object instance in the heap memory, which is equivalent to an alias for an array or object.
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First of all, you have to understand what a variable is. The essence of a variable is a small memory unit, which stores the value of the variable
For example, int a = 1;
a is the name of the variable, and 1 is the value of the variable.
When a variable points to an object, the variable is called a reference variable
For exampleA a =new A();
a is a reference variable. It points to an A object. It can also be said that it refers to an A object. We operate the A object by manipulating this a. At this time, the value of variable a is the address of the object it refers to.
If you have learned C, you can think of it as a pointer. Although it is actually different from a pointer, conceptually it is not impossible to use it as a pointer in JAVA.
Java's reference variable is actually a pointer. It points to an object instance in the heap memory. It is equivalent to an alias for an array or object. You can use the stack in the program later. A reference variable to access an array or object in the heap.
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