What are the 4 states of thread in Java?
What are the 4 states of thread in Java?
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In Java, a thread is a single flow of program execution that can run concurrently with other threads. There are four main states of a thread in Java:
Newborn State: This state refers to the creation of a new thread object. When you create a new Thread object, it enters the newborn state, where it doesn't have its own stack or native resources. At this point, the thread is not yet running. Runnable State: As soon as the thread's start() method is called, it transitions into the runnable state. In this state, the thread has a valid thread ID and can be scheduled to run by the operating system. The thread is still waiting for its turn to execute, but it's ready to go. Running State: When a thread enters the running state, it's executing code at runtime. This means the thread is consuming CPU resources, performing I/O operations, or waiting on some other resource. The running state is where most of the action happens! It's also worth noting that Java threads can be interrupted or paused while they're in this state. Dead State: Finally, when a thread has finished its execution or has been terminated (e.g., due to an exception), it enters the dead state. This state indicates that the thread is no longer alive and cannot be restarted or resumed. Dead threads are essentially garbage collected like any other Java object.Additional notes:
You can also consider another state, Waiting State, which occurs when a thread is waiting for some event or resource (e.g., waiting for a lock, I/O completion, or a condition variable). Some sources might group the states differently, such as considering the newborn state to be part of the runnable state. However, in general, the four main states (newborn, runnable, running, and dead) are widely recognized.Hope this helps! Let me know if you have any further questions
state pattern java
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Here's my answer:
public class Singleton {private static Singleton instance = null;
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