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

Write a java applet using swing components, The project is optional. It is ...

The project is optional. It is worth at least 7 bonus points beyond overall 100 points of this course. The grading will be on a pass/fail basis. Write a Java application (not ap

Big m method, i''ve done an application that calculates simplex methods i n...

i''ve done an application that calculates simplex methods i need to add big m method can any one help me?

Define high-level thread states?, The state chart diagram given below defin...

The state chart diagram given below defines the thread states.     1.      Runnable - waiting for its turn to be picked for performing by the thread scheduler based o

What system.out.println() signifies, What 'System.out.println()' signifies?...

What 'System.out.println()' signifies? 'System' is a predefined class. System class gives access to the system. 'out' is the output stream. 'println' is printin

Bidirectional currency conversion, Write a AXIS2 SOAP Java Web Service that...

Write a AXIS2 SOAP Java Web Service that performs a bidirectional currency conversion for the following currencies- GBP, EUR and USD (American Dollar). You are allowed to hardco

What is a portal?, A portal is a service or a Web site that gives broad ran...

A portal is a service or a Web site that gives broad range of services and resources like e-mail, forums, search engines, weather information, news, on-line shopping, stock quotes.

Authorization-security compnent, Define : Authorization is the process by ...

Define : Authorization is the process by which a program calculates whether a given identity is permitted to access a source such as an application component or a file. Now that y

Java pass arguments by value or reference, Does Java pass arguments by valu...

Does Java pass arguments by value or reference? Ans) Pass by value. 1. When passing primitives, it going a copy of the variable to the method. Any change made in the method d

Jsp retrive data, how to retrive data in one block from database by click ...

how to retrive data in one block from database by click data link in another block

Constructors or destructors in java program, Consider the following Java de...

Consider the following Java definition of an integer list class. class IntegerList { private int[] list = new int[200]; private int size = 0; public boolean append(int value) {

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