What will happen if we call run () directly without start ()?

If you call it directly, then it will execute not in another thread, but in the current thread. If start isn't called, then the Thread created will never run. The main thread will finish and the Thread will be garbage collected.

What happens if we call run directly instead start () method?

If run() method is called directly instead of start() method in Java code, run() method will be treated as a normal overridden method of the thread class (or runnable interface). This run method will be executed with in the context of the current thread not in a new thread.

Why do we need run () and start () method?

start() and run() methods are used for running a thread. The run() method is just an ordinary method, it is overridden by the user and it will be called on the current thread. The start() method runs the run() method indirectly and creates a new thread.

What is difference between starting thread with Run () and start () method there is no difference run () calls start () method internally when you call?

Difference between start and run in Java Thread

Main difference is that when program calls start() method a new Thread is created and code inside run() method is executed in new Thread while if you call run() method directly no new Thread is created and code inside run() will execute on current Thread.

What is run () and start () method?

run() methods: New Thread creation: When a program calls the start() method, a new thread is created and then the run() method is executed.

What if we call the run() method directly instead of start() method? | Java Threads

What happens when you call the run () method instead of start () of a thread class *?

The run method is just another method. If you call it directly, then it will execute not in another thread, but in the current thread. If start isn't called, then the Thread created will never run. The main thread will finish and the Thread will be garbage collected.

Can we call the run () method instead of start in Java?

No, you can not directly call run method to start a thread. You need to call start method to create a new thread. If you call run method directly , it won't create a new thread and it will be in same stack as main.

What is difference between starting thread with Run () and start () method in Mcq?

Explanation: run() method is used to define the code that constitutes the new thread, it contains the code to be executed. start() method is used to begin execution of the thread that is execution of run(). run() itself is never used for starting execution of the thread.

What is difference between starting thread with Run () and start () method *?

start method of thread class is implemented as when it is called a new Thread is created and code inside run() method is executed in that new Thread. While if run method is executed directly than no new Thread is created and code inside run() will execute on current Thread and no multi-threading will take place.

Can we overload run () method What if we do not override the run () method?

Answer: If we don't override run() method, compiler will not flash any error and it will execute run() method of Thread class that has empty implemented, So, there will be no output for this thread.

What does start () do in Java?

The start() method of thread class is used to begin the execution of thread. The result of this method is two threads that are running concurrently: the current thread (which returns from the call to the start method) and the other thread (which executes its run method).

How does run () method is invoked?

The run() method of thread class is called if the thread was constructed using a separate Runnable object otherwise this method does nothing and returns. When the run() method calls, the code specified in the run() method is executed. You can call the run() method multiple times.

What happens when we call thread start ()?

start() method causes this thread to begin execution, the Java Virtual Machine calls the run method of this thread. The result is that two threads are running concurrently: the current thread (which returns from the call to the start method) and the other thread (which executes its run method).

Can we start thread twice?

No. After starting a thread, it can never be started again. If you does so, an IllegalThreadStateException is thrown. In such case, thread will run once but for second time, it will throw exception.

What will happen in a scenario where you do not override the thread class run () method?

Answer: If we don't override run() method, compiler will not flash any error and it will execute run() method of Thread class that has empty implemented, So, there will be no output for this thread.

Which method is called internally by thread start () method execute () run () launch () main ()?

Q) Which method is called internally by Thread start() method? Thread start() method internally calls run() method. All statements inside the run method is get executed by the thread.

Can we override Run method?

Answer: Yes, we can override start() method of thread in Java, the same way we override any other methods. for example, In below, custom thread class MyThread, both start() method and run() method have been overridden.

Can two threads have same priority?

It is possible to have same priority to threads. So CPU can decide which thread to run by using some algorithms.

Can we restart thread?

Once a thread enters dead state it cannot be restarted.

What is the difference between runnable interface and thread class?

Runnable is an interface which represents a task that could be executed by either a Thread or Executor or some similar means. On the other hand, Thread is a class which creates a new thread. Implementing the Runnable interface doesn't create a new thread.

What will happen if two threads try to read same resource without synchronization in Java?

When more than one thread try to access same resource without synchronization causes race condition. So we can solve race condition by using either synchronized block or synchronized method.

Can we execute a program without main () method?

Yes, we can execute a java program without a main method by using a static block. Static block in Java is a group of statements that gets executed only once when the class is loaded into the memory by Java ClassLoader, It is also known as a static initialization block.

Is daemon a thread?

A Daemon thread is a background service thread which runs as a low priority thread and performs background operations like garbage collection. JVM exits if only daemon threads are remaining. The setDaemon() method of the Thread class is used to mark/set a particular thread as either a daemon thread or a user thread.

What is difference between notify and notifyAll?

In case of multiThreading notify() method sends the notification to only one thread among the multiple waiting threads which are waiting for lock. While notifyAll() methods in the same context sends the notification to all waiting threads instead of single one thread.