What is the meaning of reference to java array

The array reference in java is to let array b point directly to array a (i.e. b = a;). The purpose of doing this in java programming is to improve the efficiency of program running.

Just imagine, if there are tens of thousands of elements in the array, when copying the array, if all the elements of array a are copied one by one to array b, it will take a lot of time. Large, sometimes not necessary.

So, in the Java language, b = a (a and b are both reference names) means to give a an alias "b".

After that, a and b actually point to the same object.

int[] a = new int[10];
int[] b;
b = a;

In Java, this mechanism for aliasing variables is called reference.

If a program wants to run, it must reside in memory, and there must be its storage address in the memory. Through these memory addresses, we can find the data we want.

These memory addresses are usually very long. Because they are not easy to remember, we give these addresses a name. This is a reference variable. These reference variables are stored in an area called "stack memory".

The so-called "reference" means that the address of the Java object in the heap memory is assigned to multiple "stack memory" variables.

Since Java prohibits users from directly operating the addresses of objects in "heap integer, floating point, Boolean and other basic data class memories", they can only use multiple reference names of these "stack memories" to indirectly Operate their corresponding "heap memory" data.

So, The "reference" in Java is more similar to the concept of "pointer" in C/C. The difference is that the "pointer" in C/C can be directly modified by the user, while Direct modification of memory is blocked in Java.

The above is the detailed content of What is the meaning of reference to java array. For more information, please follow other related articles on the PHP Chinese website!