JAVA MULTI-THREADING Design and implement a barrier using monitors. Your barrier should
support one method, namely arriveAndWait( ). A thread invoking the
method is blocked until all threads have arrived at the barrier (in
other words, invoked the arriveAndWait( ) method of the barrier)
at which point all threads are released from the barrier and can
resume their respective executions. The barrier should be reusable,
that is, threads can use the same barrier object multiple times to
synchronize with each other. Ensure that your design and
implementation of a barrier satisfies the following two properties:
(a) safety: no thread is released from the barrier prematurely,
and (b) liveness: once all threads have arrived at the barrier,
all threads are released from the barrier eventually.

Avariable definition defines the name of a variable that will be used in a program, as well as

File account.java (see previous exercise) contains a definition for a simple bank account class with methods to withdraw, deposit, get the balance and account number, and return a string representation. note that the constructor for this class creates a random account number. save this class to your directory and study it to see how it works. then write the following additional code: 1. suppose the bank wants to keep track of how many accounts exist. a. declare a private static integer variable numaccounts to hold this value. like all instance and static variables, it will be initialized (to 0, since it’s an int) automatically. b. add code to the constructor to increment this variable every time an account is created. c. add a static method getnumaccounts that returns the total number of accounts. think about why this method should be static - its information is not related to any particular account. d. file testaccounts1.java contains a simple program that creates the specified number of bank accounts then uses the getnumaccounts method to find how many accounts were created. save it to your directory, then use it to test your modified account class.

Match the sentence fragment in the first column with the appropriate ending in the second column. a little per favore?