What is an object reference in java

What is an object reference in java

1. The concept of reference

If a variable The type is a class type, not a basic type, then the variable is also called a reference. In fact, GC mainly depends on whether the object has a reference pointing to the object. According to the strong and weak relationship of this reference, starting from JDK1.2 version, object references are divided into four levels, so that the program can more flexibly control the life cycle of the object. These four levels, from high to low, are: strong reference, soft reference, weak reference and virtual reference.

2. Object reference

Reference and pointer

new Hero(); represents the creation of a Hero object, but it only creates an object and has no way to access it. In order to access this object, a reference will be used to represent the object Hero h = new Hero();

hThis variable is of type Hero, also called a reference, = It means that the reference h represents the object created on the right "representative". In object-oriented, it is also called "pointing".

So, the reference to an object in Java is a class type variable pointing to the created object.

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