What are the ways in which we can synchronize a singleton class?
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What are the ways in which we can synchronize a singleton class?
There are three ways through which we can achieve thread safety.
- Create the instance variable at the time of class loading.
- Synchronize the getInstance() method.
- Use synchronized block inside the if loop and volatile variable.
What happens when two threads access singleton at the same time?
Now coming to your question: if you share your singleton object among multiple threads and access it concurrently, every single thread will execute Singleton object’s portion of code, wrapped in its own execution. Also if you write a Thread.
Is Singleton design pattern thread safe?
Is singleton thread safe? A singleton class itself is not thread safe. Multiple threads can access the singleton same time and create multiple objects, violating the singleton concept. The singleton may also return a reference to a partially initialized object.
Can we serialize singleton class in Java?
Suppose if you serialize the Singleton class, and then again de-serialize that object, it will create a new instance, hence deserialization will break the Singleton pattern. The below code is used to illustrate how the Singleton pattern breaks with deserialization. Implements Serializable interface for Singleton Class.
How do you synchronize Java?
Synchronization in Java is the capability to control the access of multiple threads to any shared resource….It can be achieved by using the following three ways:
- By Using Synchronized Method.
- By Using Synchronized Block.
- By Using Static Synchronization.
How can we prevent race condition in Singleton design pattern?
As I understand, Data race can be avoided by making sure that one or more of the above conditions hold false – ie, by making shared variables immutable or by making the access to them properly synchronized .
Why do we need volatile in singleton?
The volatile prevents memory writes from being re-ordered, making it impossible for other threads to read uninitialized fields of your singleton through the singleton’s pointer.
What is Singleton is it better to make the whole method synchronized or only critical section synchronized?
Since synchronization is only needed during initialization on singleton instance, to prevent creating another instance of Singleton, It’s better to only synchronize critical section and not whole method.
Can Run method be synchronized?
Yes, we can synchronize a run() method in Java, but it is not required because this method has been executed by a single thread only. Hence synchronization is not needed for the run() method.
Can singleton class be cloned?
clone method is protected and you cannot subclass a singleton class.
What is the best way to implement singleton in Java?
1. Eager initialization: In eager initialization, the instance of Singleton Class is created at the time of class loading, this is the easiest method to create a Singleton class. By making the constructor as private you are not allowing other class to create a new instance of the class you want to create the Singleton.
What is Java synchronized?
Synchronization in java is the capability to control the access of multiple threads to any shared resource. In the Multithreading concept, multiple threads try to access the shared resources at a time to produce inconsistent results. The synchronization is necessary for reliable communication between threads.
Why singleton beans are not thread-safe?
Singleton spring beans has no relation with thread safety. spring container only manages life-cycle of objects and guaranteed that only one object in spring container. so If an Non thread safe object is injected then obviously it is not thread safe. To make it thread safe you have to handle it by coding.
Can we modify singleton object Java?
From your singleton class, if the object is created then no objects are allowed to modify the someNum & someString values because of a singleton pattern.
Is volatile required in singleton?
You need volatile on the member fields of the singleton itself (apply visibility feature). If you do more then an atomic action on mutable state, you will need to use synchronized , even though the field is declared volatile (apply mutual exclusion feature).
