#README
Author: Jacob Lipson
Date: 4/26/2015
Description: An implementation of a First-in, First-out priority queue
Files: Task.java, TaskQueue.java, TaskResult.java, Test.java
Status: Task, TaskQueue, and TaskResult are fully implemented. Task's execute method has temporarily been modified to return a TaskResult. TaskResults has not yet been implemented. Task has been thoroughly tested. TaskQueue has been tested. TaskResult has not been tested.
###To Run:
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Clone the repository from Github
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Open a terminal window or command line and navigate to the folder 'flashnotes-challenge'.
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Modify the file Test.java to run whatever tests you'd like, or import your own test file
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Run the following compile script: javac *.java
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Run the following test script: java Test
###Class Descriptions
####Task Members:
GUID - Randomly created, unique identifier generated by Java's UUID class
description - Text provided at creation of Task instance
command - Command line code provided at creation of Task instance
Methods:
execute() - Runs the Task's stored command in the application's environment, creates a TaskResult and returns it
####TaskQueue Members:
queue - Linked List used to represent the FIFO queue
Methods:
push() - Adds a task to the bottom of the queue
pop() - Removes and returns the task on the top of the queue
peek_next() - Returns a copy of the task on the top of the queue
peek_all() - Returns a Java List of copies of the tasks on the queue in proper order
count() - Returns the size of the queue
###TaskResult Members:
task_guid - the original task's GUID
suceeded - boolean for if task ran without exception
return_code - the return code the task's execute returns
output - the stdout dump for the task in String format
exception - if an exception occurred, String containing message, else empty String
execution_duration - length of time the task took to run in nanoseconds
###Design Choices: I chose to solve this problem in Java as it is both my most comfortable programming language, and one that easily lent itself to a solution. Java's numberous libraries made solving the various challenges in this problem simple. I chose a Linked List as the data structure to represent the TaskQueue because it offered methods for every feature of the TaskQueue, except peek_all. For peek_all, it was equally easy to copy the Linked List into an ArrayList, then into a List. Java also offered the UUID class, for easy GUID creation.