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.


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

Advantages java layout managers over traditional windowing, What are the ad...

What are the advantages that Java's layout managers provide over traditional windowing systems ?

Unix-like CLI in Java (simple), The assignment is implementing a CLI in Jav...

The assignment is implementing a CLI in Java with several usable commands, using Threads.

Prepare a new fishing app, New Fishing App Project Description: A new...

New Fishing App Project Description: A new app for iPhone providing a GPS connected map of the fishery you are fishing at and other logged in users who are also fishing at th

Create sudoku in java, The SudCell Class A single cell in a Sudoku ...

The SudCell Class A single cell in a Sudoku must clearly represent a number from 1 to 9 .  But in a solver context, we need much more.  It isn't enough to say "this c

Create an online multiple choice quiz, Create an online multiple-choice qui...

Create an online multiple-choice quiz using JSP/Servlets technology. The quiz should draw questions from an array of predefined questions (at least fifteen). You should use a meani

Develop a computer program and application, Develop a Computer program and ...

Develop a Computer program and application. Project Description: I want a project done. It is a computer desktop application program. It is not very hard. If you need the det

Define the life cycle methods of a servlet? , The Web container is used for...

The Web container is used for managing the servlet's life cycle. The Web container produces an instance of the servlet and then the container invokes the init() function. At the co

What are not allowed within the ejb container? , In  order  to  provide  po...

In  order  to  provide  portable  and  reliable  EJB  elements,  the  following  restrictions  apply  to  EJB  code implementation: 1. Avoid using static non-final fields. Defin

Please answer this, Assignment Help >> JAVA Programming Learning Outcomes:...

Assignment Help >> JAVA Programming Learning Outcomes: 1. Use different program control statements in a programming language 2. Demonstrate the use of arrays with a programming

What is java bytecode, What is java Bytecode Java programs (Source code...

What is java Bytecode Java programs (Source code) are compiled into a form known as Java bytecodes. Java compiler reads Java language source (.java) files, translates source

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