Four reference modes of Java

JAVA memory management is divided into memory allocation and memory recycling, which are not the responsibility of programmers. The garbage collection mechanism mainly depends on whether the object has a reference to the object.

Java object references include strong references, soft references, weak references and virtual references

These four reference types are provided in Java for two main purposes:

The first is that programmers can determine the life cycle of some objects through code;

The second is to facilitate JVM garbage collection.

The following describes the concepts of these four types of references:

1. Strong reference

Creating an object and assigning it to a reference variable.

For example: