Concurrent Programming, JAVA Programming

Assignment Help:
Problem 1
A savings account object holds a non-negative balance, and provides deposit(k )
and withdraw(k ) methods, where deposit(k ) adds k to the balance, and
withdraw(k ) subtracts k, if the balance is at least k, and otherwise blocks until
the balance becomes k or greater. getbalance() gives the current balance.
1. Implement this savings account using locks and conditions (use
java.util.concurrent.locks.ReentrantLock). Test by using the 3
functions.
2. Now suppose there are two kinds of withdrawals: ordinary and preferred.
Devise an implementation that ensures that no ordinary withdrawal occurs
if there is a preferred withdrawal waiting to occur.
Problem 2
Consider the following conditions: An enqueuer waiting on a full-queue or
a dequeuer waiting on an empty queue sleep indefinitely, unless woken up by
another thread. A thread must send a signal ONLY when it adds an element
to an empty queue or removes an element from a full-queue.
1. Implement a bounded partial queue using a signaling mechanism that
signals to all waiting dequeuers.
2. Implement the bounded partial queue by using a signaling mechanism
(your own scheme) that signals to only one waiting dequeuer or enqueuer,
and ensure that the lost-wake-up problem does not happen.
1
Problem 3
We have n threads, each of which executes method foo() followed by bar().
We want to add synchronization to ensure that no thread starts executing bar()
until all threads have finished executing foo(). To achieve this, we will insert
some barrier code between the two methods. Implement the following two
schemes for barrier code:
• Use a shared counter protected by test-and-test-and-set lock. Each thread
locks the counter, increments it, releases the lock, and repeatedly reads
the counter until it reaches n.
• Use an n-element Boolean array A. Initially all entries are 0. When thread
0 executes its barrier, it sets b[0] to 1, and repeatedly reads b[n - 1]
until it becomes 1. Every other thread i, repeatedly reads b[i - 1] until
it becomes 1, then it sets b[i] to 1, and repeatedly reads b[n - 1] until
it becomes 1.
Implement both these schemes in Java. Each of the methods foo() and
bar() just sleeps for 20 milliseconds. Test the two schemes for n = 16. Run
each scheme at least ten times, measure the total runtime in each test run,
discard the highest and lowest values, take the average, and use it to compare
the two schemes. Which performs better? Can you explain the reason? You
can run the experiments on ecen5033.colorado.edu. Submit the code as well as
experimental results.

Related Discussions:- Concurrent Programming

Programming, write a Java program that accept two integers and determine we...

write a Java program that accept two integers and determine weather they are Coprime or not

Explain what is local variable, Explain what is Local Variable ? Declar...

Explain what is Local Variable ? Declaring variables (using the var keyword) inside a function forms them local. They are available only inside the function and hold no meaning

Describe validate() and reset() methods, Validate() : Used to validate prop...

Validate() : Used to validate properties after they have been populated; known as before FormBean is handed to Action. Returns a collection of ActionError as ActionErrors. Followin

What are the principle concepts of oops, What are the principle concepts of...

What are the principle concepts of OOPS? Principle concepts upon that object oriented programming and design rest. They are: Abstraction: Abstraction refers to the act of

How to loading images in java, How to Loading Images in JAVA? Polygons,...

How to Loading Images in JAVA? Polygons, ovals, lines and text cover a lot of ground. The residual graphic object you need is an image. Images in Java are bitmapped GIF or JPEG

Java Login/Register Web CMS, I need help setting up and fleshing out a basi...

I need help setting up and fleshing out a basic outline/structure for a basic Java web app using an MVC pattern

What is the use of textmessage, TextMessage having instance of java.lang.St...

TextMessage having instance of java.lang.String as its payload. Therefore it is very useful for exchanging textual data. It can also be used for exchanging difficult character data

Determine about the wrapper classes, Determine about the Wrapper Classes ...

Determine about the Wrapper Classes Every primitive data type has a corresponding object (wrapper class). These wrapper classes provides extra functionality (conversion, size c

Ps1 emulator for android, PS1 emulator for android There is an open sour...

PS1 emulator for android There is an open source app known as psx4droid i want a developer to solve problems and bugs and doing performance improvement to source code to running

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd