espressOS
espressOS
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This assessment is CONFIDENTIAL. © University of Sydney.
Due date
11:59PM Sunday 04 November 2018 AEST
You are tasked with writing a phone OS for EspressOS Mobile that will be installed on their
products. You are required to write the software using the Java programming language.
EspressOS OS must support the following features:
Battery life
Network connection
Signal Strength
Charging a phone
Manage contact data
Being able to copy contacts
Delete contacts
Add contacts
Update contact details
Copy contacts
Manage messages
Add messages
Clear messages
Get latest and oldest messages
Run applications
The given properties of the class cannot be removed and their data type and modifiers cannot
be changed.
You are provided with a scaffold and comments that describe the methods required to
implement. Each method’s comments desribes the process necessary to implement.
Factory Defaults
Every phone manufactured and installed with EspressOS OS. The default factory settings are:
Phone is off
Phone has battery life (25)
Not connected to a network
No Signal (signal strength is 0)
Owner contact factory default on the device:
First Name: EspressOS
Last Name: Incorporated
Phone Number: 180076237867
One message should be included under this contact: “Thank you for choosing
EspressOS products” .
Stored as “EspressOS: Thank you for choosing EspressOS products”
The contact list should not contain ANY other contacts on first boot.
If the factory defaults do not match it can be suspected that the hardware contains a fault and
requires inspection. By ensuring the software clearly adheres to the correctness of what is
specified, this can be ruled out.
Battery and Charging
The OS needs to keep track of the battery level and implement functions related to battery
changing, charging and status. The battery level is represented as an integer between 0 and 100
inclusive. [0, 100]
isPhoneOn
getBatteryLife
changeBattery
chargePhone
usePhone
setPhoneOn
isPhoneOn
This method checks if the phone is on or not
getBatteryLife
Retrieves the battery life which is represented as value between 0 and 100.
changeBattery
Changes the battery and therefore changing the battery level. The phone is switched to the off
state after this operation and the battery life is updated. If the new battery’s level is outside of
the range accepted (n < 0 OR **n** > 100) then it should be rejected and no update should
occur.
chargePhone
The phone is charged and battery life increases by 10. In the event that the battery life exceeds
100, the charge becomes 100. A charge would not occur and the method should return false in
the event that nothing has changed.
usePhone
will reduce the battery level by k units of battery level. The phone will turn off if the use causes
the battery level to reach 0.
setPhoneOn
Turning the phone on will reduce the battery level by 5, if the battery level is < 6 the phone should not power on. Network Connectivity and Signal A baseline feature to a phone is determining the network connectivity status and updating it. The network status has two parts. Network is connected and Signal strength. Signal strength is represented as a range between 0 and 5 inclusive [0,5]. 0 representing that the phone is not connected to a network while all numbers > 0 infer that the phone is connected to a network.
isConnectedNetwork
disconnectNetwork
connectNetwork
getSignalStrength
setSignalStrength
changeAntenna
isConnectedNetwork
Reports if the phone is connected to a network
connectNetwork
Connects to a network if needed otherwise does nothing. When connecting to network, sets the
signal strength to 1 if the signal strength is currently set to 0. Sets the signal strength to the last
known value of signal strength if it is not currently set to 0. If the network needs to connect, this
process will reduce the battery life by 2.
disconnectNetwork
Disconnects from a network and sets the signal strength to 0
getSignalStrength
Returns an integer value between 0 and 5 [0,5], that represents the signalStrength
setSignalStrength
Sets the signal strength to n, where n must be in the range of [0,5]. If n is inside of the range of
[0,5] the method will be successful.
changeAntenna
Changes the antenna with different antenna object. This will be used to replace broken
antennas. Signal strength starts at 0 and is disconnected from a network.
If the phone is not connected to a network and n > 0, it will connect to a network and reduce
the battery life by 2.
If the phone is connected to a network, the signal strength value is updated. If the signal
strength is zero, it will disconnect the network, while a signal strength of > 0 will not change the
network connected status.
If n is outside of the range of [0,5], or the phone is off, this method should not affect the mobile
and specify that it did not successfully update.
Contact Management
The OS allows for the user to manage contacts by being able to search, remove and add
contacts. The maximum number of contacts that can be stored on the device is 10 plus the
owner contact.
The following methods require to be implemented:
searchContact
addContact
removeContact
getCopyOfOwnerContact
getNumberOfContacts
searchContact
A user would want to find contacts that are stored on their phone. Given a name a user could
use an input, the OS should check to see if the contact’s first name or last name match the
given input.
The method can return more than one result if the string is matched multiple times. If the
phone is off, the method should not proceed to execute and instead return no entries.
addContact
Given a EspressOSContact, the OS should add this contact to the contact list. Only when there is
enough space to do so. If phone is off, the method should not add a contact and return that
adding the contact failed.
removeContact
Given a EspressOSContact, the OS should remove this contact from the contact list. It is
successful if the contact was found and removed. Otherwise failed. If phone is off, the method
should not remove a contact and return that adding the contact failed. Invalid contact, such as
null, will result in fail.
getNumberOfContacts
Return the number of active contacts. This is possibly less than the maximum.
Contacts
A baseline feature that is required to be implemented is contact management. Each contact has
a:
First name
Last Name
Phone Number, cannot be less than 6 digits or greater than 14 digits.
and Chat History
The fields First Name, Last Name and Phone Number can be updated by the user. A first and
last name can be of any length and cannot be set to null. Each contact will have these methods
associated with it:
getFirstName
getLastName
getPhoneNumber
updateFirstName
updateLastName
updatePhoneNumber
copy
getFirstName, getLastName, getPhoneNumber
Retrieves the respective properties associated with the method name.
updateFirstName, updateLastName, updatePhoneNumber
Allows updating/changing the properties associated with the method name.
copy
This method allows a contact to be duplicated, this would be used if a contact has two phone
numbers and the user would like to duplicate the user and update the phone number on one
of them. This method should create a copy of EspressOSContact object.
Messaging
Messages are stored for each contact on the phone. Each contact can contain a maximum of 20
messages and once messages exceed that limit it will overwrite existing messages.
There are 5 methods that are required to be implemented:
addChatMessage
getLastMessage
getOldestMessage
clearChatHistory
addChatMessage
When a message is sent to the phone, the EspressOS needs to store it and be able to retrieve it
based on the contact.
The message format of a chat message when stored in the chat history is whoSaidIt + “: ”
+ message . When two contacts communicate, the first name is whoSaidIt .
getLastMessage
This method should retrieve the last message from a contact, if this contact has no messages,
the method should return null.
getOldestMessage
This method should retrieve the oldest message in the chat history for a contact.
Application (Feature)
EspressOS needs to support third party applications. You will need to implement the Apps
feature that will allow a variety of third party applications to run on the system. Apps can
implement different behaviour that will allow them to interact with different resources of the
system. Currently only two behaviours are to be implemented, Background and Notify.
Apps have the following methods
start
This method starts the execution of an app, this method does not return any values or
accept
exit
Will quit the process with an exit code.
EspressOS will need to implement the following methods to support Apps.
install
Installs an app on the operating system. If the object passed is null then an app will not be
installed. If the app has been installed already, then the app will not be installed. The
method returns the value true if the app has been successfully installed, otherwise false.
uninstall
Given a name of an app, it will find the app and remove it from the operating system. If the
app exists and has been uninstalled it will return true, otherwise the method returns false.
getRunningApps
Returns a List of all running applications on the operating system.
getInstalledApps
Returns a List of all installed applications on the operating system.
getBackgroundApps
Returns a List of all Background applications on the operating system.
getNotificationApp
Returns a List of all Notify applications on the operating system.
getNotifications
Returns a List of all notifications that have been created and sent to the operating systems
by Notify apps.
run
Given an application name, it will find the application and invoke the .start() method. If
the application exists, the method will invoke the .start() method and return true.
Otherwise the the method returns false.
close
Given an application name, it will find the application that is currently running and invoke
the .exit() method. This method is commonly associated with Background apps as they
will have asynchronous execution.
Background Apps
Background apps require implementation of two methods and utilisation of the
BackgroundThread class that has been provided. Background apps will run in a loop until
specified. They can exit by calling the exit() method associated with the BackgroundThread
object which will allow it to end on its next loop.
backgroundStart
.start() is typically invoked by operating system. Since the .start() methd will be reserved for
setting a BackgroundThread, your application’s start method will be in
.backgroundStart().
getData
Background applications provide an interface that allows other applications and the
operating system to extract data from. Your background app will provide a getData
method that will return an Object and allows an Object to be passed to it.
Notify Apps
Applications can utilise generate notifications and will interact with the EspressOS’s own
notification collection. Notify apps will create a notification that the user will be able to read.
notifyOS
This method will create a notification that will be sent to the operating system.
Notifications can be retrieved using getNotifications method.
As part of development of these features, you will need to produce a set of test cases that will
ensure that the feature has been implemented correctly. Consider test case coverage and the
variety of cases that may arise with these apps.
About tests
Tests for the assignment will be released progressively.
Evaluation
This assessment contributes 10% to your final grade and is broken down into the following
components.
Automatic Test Cases (6%)
Manual Marking (4%)
Implementation of the application feature (2%)
Create appropriate classes and interfaces for your implementation.
Utilise object oriented principles such as inheritance and generics.
Test cases (2%)
Test cases for Antenna and Battery.
Test cases for the App feature.
Academic Declaration
By submitting this assignment you declare the following:
I declare that I have read and understood the University of Sydney Academic Dishonesty and
Plagiarism in Coursework Policy, and except where specifically acknowledged, the work contained in
this assignment or project is my own work, and has not been copied from other sources or been
previously submitted for award or assessment.
I understand that failure to comply with the the Academic Dishonesty and Plagiarism in Coursework
Policy, can lead to severe penalties as outlined under Chapter 8 of the University of Sydney By-Law
1999 (as amended). These penalties may be imposed in cases where any significant portion of my
submitted work has been copied without proper acknowledgement from other sources, including
published works, the internet, existing programs, the work of other students, or work previously
submitted for other awards or assessments.
I realise that I may be asked to identify those portions of the work contributed by me and required to
demonstrate my knowledge of the relevant material by answering oral questions or by undertaking
supplementary work, either written or in the laboratory, in order to arrive at the final assessment
mark.
I acknowledge that the School of Information Technologies, in assessing this assignment, may
reproduce it entirely, may provide a copy to another member of faculty, and or communicate a copy
of this assignment to a plagiarism checking service or in house computer program, and that a copy
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*Warning: Any attempts to deceive or disrupt the marking system will result in an immediate
zero for the entire assignment. Negative marks can be assigned if you do not properly follow
the assignment specification, or your code is unnecessarily or deliberately obfuscated.*
espressOS