How to identify objects in memory that have no references?

In Java, objects that have no references are considered unreachable and are eligible for garbage collection. To identify such objects, memory profilers (e.g., VisualVM, YourKit, Eclipse MAT) can be used, which display objects in the heap and their references.

Detection principle:

• The garbage collector starts with root objects (stack, static fields, etc.) and marks all reachable objects.
• Objects that are not marked are considered unreachable and can be removed.

Example with VisualVM:

1. Run the application with profiling enabled.
2. Take a heap dump.
3. Analyze objects and their references.
4. Find objects without references — they are candidates for garbage collection.