Singleton in Spring vs Java Singleton.

Java Singleton:

• Scoped to the ClassLoader.
• Only one instance of the class exists in the JVM.
• Typically implemented with a private constructor and a static method.

Spring Singleton Bean:

• Scoped to the ApplicationContext (IoC Container).
• Only one instance of the bean exists per container.
• If you have multiple containers (rare in standard apps), you could have multiple instances.

Thread Safety:

• No, Spring Singleton beans are not inherently thread-safe. They are shared across all requests. You must ensure they are stateless to avoid concurrency issues.