Can multiple threads exist on one object?

As multiple threads exists on same object. Only one thread can hold object monitor at a time. As a result thread can notify other threads of same object that lock is available now.

Can you have multiple threads?

Multithreading is a model of program execution that allows for multiple threads to be created within a process, executing independently but concurrently sharing process resources. Depending on the hardware, threads can run fully parallel if they are distributed to their own CPU core.

Can multiple threads access a singleton?

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 multiple threads hold a lock on the same object?

With locking, deadlock happens when threads acquire multiple locks at the same time, and two threads end up blocked while holding locks that they are each waiting for the other to release.

Can multiple threads write to the same file?

Multiple threads can read and write the same file in several situations: Multiple threads read the same file at the same time. In this case, there is no conflict. If multiple threads write the same file at the same time, write data will be lost.

Multithreading in Java Explained in 10 Minutes

How do you process multiple files simultaneously using multithreading in Java?

How can we avoid deadlock in multithreading?

Can two threads execute two methods?

Yes, both the calls will execute successfully. non-synchronized methods.

Can we use static and synchronized together?

static methods can be synchronized. But you have one lock per class. when the java class is loaded coresponding java.

Are singleton objects shared across threads?

In a Singleton Object you have: Fields: They are stored in memory. They can be shared amongst multiple threads and you have no guarantee they will keep consistent (unless you make them synchronized).

How do you handle singleton in multithreading?

Why singleton beans are not thread safe?

If there is any global variable defined the singleton class then it will not be thread safe because if multiple thread share the singleton object and execute the method which can updates the global variable it will not be thread safe.

Can two threads run on same core?

A thread is short for thread of execution. One processor core can only execute one instruction at a time ( ignoring modern CPUs that can do integer and floating point arithmetic at the same time). So two cores can run two threads simultaneously.

Can multiple threads run on the same core?

It's up to the OS where a thread is scheduled. There are advantages to keeping a thread on the same core if possible, in terms of cache coherency etc — but forcing it to stay on the same core is usually overly restrictive. In short: yes, a thread can run on different cores.

How many threads can run at once?

Each core can only run 1 thread at a time, i.e. hyperthreading is disabled. So, you can have a total maximum of 20 threads executing in parallel, one thread per CPU/core.

Can two threads execute static and non static method concurrently?

Since both the objects are different hence both synchronized static and non-static method will not block each other in case of multi-threading. Both the methods will execute simultaneously. Show activity on this post. Yes..

Which is better synchronized block or method?

To acquire a lock on an object for a specific set of code block, synchronized blocks are the best fit. As a block is sufficient, using a synchronized method will be a waste. More specifically with Synchronized Block , it is possible to define the object reference on which are want to acquire a lock.

How can a thread own the lock of an object?

When a thread invokes a synchronized method, it automatically acquires the intrinsic lock for that method's object and releases it when the method returns. The lock release occurs even if the return was caused by an uncaught exception.

Can a threads access another synchronized methods on an object?

No. If a object has synchronized instance methods then the Object itself is used a lock object for controlling the synchronization. Therefore all other instance methods need to wait until previous method call is completed. See the below sample code which demonstrate it very clearly.

Can synchronized method be overridden?

Synchronized method Overriding !!

Above code compiles ,so answer to above question is “yes,synchronized method can be overriden” .

Can a deadlock happen with three threads?

This type of deadlock is commonly encountered in multi-threaded applications. A process with two or more threads can enter deadlock when the following three conditions hold: Threads that are already holding locks request new locks. The requests for new locks are made concurrently.

What is Ostrich Algorithm in OS?

In computer science, the ostrich algorithm is a strategy of ignoring potential problems on the basis that they may be exceedingly rare. It is named after the ostrich effect which is defined as "to stick one's head in the sand and pretend there is no problem".

What is starvation in Java?

Starvation describes a situation where a thread is unable to gain regular access to shared resources and is unable to make progress. This happens when shared resources are made unavailable for long periods by "greedy" threads.

What is multithreading in Java?

In Java, Multithreading refers to a process of executing two or more threads simultaneously for maximum utilization of the CPU. A thread in Java is a lightweight process requiring fewer resources to create and share the process resources.