INFO1113 Assignment 1

This assignment is worth 6% of your final assessment

Task Description

In this assignment you will develop a banking administrative system called BankerOS in the Java programming 

language. All bank accounts within the system will contain various details relating to the owner of the 

account. Each account is identified by a unique account number and maintains a history of transactions 

received and sent.

You are encouraged to ask questions on Ed using the assignments category. As with any assignment, make 

sure that your work is your own, and you do not share your code or solutions with other students.

Working on your assignment

You can work on this assignment on your own computer or the lab machines. It is important that you 

continually back up your assignment files onto your own machine, external drives, and in the cloud.

You are encouraged to submit your assignment on Ed while you are in the process of completing it. By 

submitting you will obtain some feedback of your progress on the sample test cases provided.

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Implementation details

Write a program in Java that implements the BankerOS application as shown in the examples below. You can 

assume that our test cases will contain only valid input commands and not cause any integer overflows. 

Commands are case insensitive.

BankerOS stores a collection of Bank Accounts and the Transactions associated with them. Bank Accounts

are identified by their account number (ACCNO), and store first name, last name, transaction history and 

current balance. By default, accounts begin with $10,000, however this can be overridden (see commands).

Balances are stored as integers to remove decimal errors. Account numbers begin from 100,000 and are 

incremental (first account is 100000, second is 100001).

Transactions store sender, receiver, amount and hash. They are indexed from 1 and have unique indices.

Both the sender and receiver must have bank accounts within the system to be a valid transaction. The hash

is generated based on the details of the transaction as well as the hash of the previous transaction to ensure 

that ledgers are not modified.

Ledgers (collections of transactions) can be archived in a human-readable text file, stored in chronological

order in the following form

Example

1, 100000, 100001, 10, 1128448214

When ledgers are archived, a second human-readable file is also created, storing the account numbers and 

names of all accounts. This is archived in the following form (in numerical order)

Example

100000, John, Smith, 10000

Archived ledgers can be restored by Banker, resetting the data to the ledger's archived state.

An account’s balance cannot go below $0. Transactions are aborted if they result in a negative balance. 

Your program can be contained within the scaffold of Banker.java, BankAccount.java and Transaction.java. 

Do not modify any of the existing method signatures in these files. Your program must produce no errors 

when built and run on the lab machines and Ed. Your program will read from standard input and write to 

standard output.

Your program output must match the exact output format shown in the examples and on Ed. You are 

encouraged to submit your assignment while you are working on it, so you can obtain some feedback. You 

have been provided simple skeleton classes and hints on how to implement your banking application.

In order to obtain full marks, your program will be checked against automatic test cases, manually inspected 

by your tutors and you must submit a set of test cases that ensure you have implemented functionality 

correctly.

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Commands

Your program should implement the following commands, look at the examples to see how they work.

• If an does not exist in the system, output: no such account

• If a does not exist in the system, output: no such transaction

EXIT exit from application

COMMANDS display the command list

LIST ACCOUNTS displays all accounts in system

LIST TRANSACTIONS displays all transactions in system

DETAILS displays all details about bank account

BALANCE displays the current balance of bank account

HISTORY displays all transactions involving an account

OUTGOING displays all transactions paid by account

INCOMING displays all transactions received by account

CREATE [] creates a bank account

RENAME renames a bank account

PAY transfers money between account

TRANSACTION displays the transaction details

CANCEL makes a copy of the transaction with receiver/sender swapped

ARCHIVE stores the transaction history as a ledger

RECOVER restores a ledger

MERGE transfers all funds from listed accounts into the first account

MAX displays the highest balance from all accounts

MIN displays the lowest balance from all accounts

MEAN displays the average balance

MEDIAN displays the median balance

TOTAL displays the amount of money stored by bank 

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Examples (1)

$ LIST ACCOUNTS

no accounts

$ LIST TRANSACTIONS

no transactions

$ DETAILS 100000

no such account

$ BALANCE 100000

no such account

$ HISTORY 100000

no such account

$ OUTGOING 100000

no such account

$ INCOMING 100000

no such account

$ RENAME 100000 John Smith

no such account

$ TRANSACTION 1

no such transaction

$ EXIT

bye

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Examples (2)

$ CREATE John Smith

success

$ CREATE Mary Jane 15000

success

$ LIST ACCOUNTS

100000

100001

$ DETAILS 100001

100001 – Mary Jane - $15000

$ BALANCE 100000

$10000

$ RENAME 100001 Mary Smith

success

$ PAY 100000 100001 10

success

$ PAY 100000 100001 10000

insufficient funds

$ PAY 100000 100000 10000

sender cannot be receiver

$ PAY 100000 100001 -1

amount must be positive

$ TRANSACTION 1

1: 100000 -> 100001 | $10 | 1128448214

$ EXIT

bye

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Examples (3)

$ CREATE John Smith

success

$ CREATE Mary Jane 15000

success

$ PAY 100000 100001 10

success

$ PAY 100000 100001 20

success

$ PAY 100001 100000 30

success

$ LIST TRANSACTIONS

1: 100000 -> 100001 | $10 | 1128448214

2: 100000 -> 100001 | $20 | 919049074

3: 100001 -> 100000 | $30 | 755697066

$ HISTORY 100000

1: 100000 -> 100001 | $10 | 1128448214

2: 100000 -> 100001 | $20 | 919049074

3: 100001 -> 100000 | $30 | 755697066

$ OUTGOING 100000

1: 100000 -> 100001 | $10 | 1128448214

2: 100000 -> 100001 | $20 | 919049074

$ INCOMING 100000

3: 100001 -> 100000 | $30 | 755697066

$ CANCEL 1

success

$ LIST TRANSACTIONS

1: 100000 -> 100001 | $10 | 1128448214

2: 100000 -> 100001 | $20 | 919049074

3: 100001 -> 100000 | $30 | 755697066

4: 100001 -> 100000 | $10 | -1389840415

$ EXIT

bye

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Examples (4)

$ CREATE John Smith

success

$ CREATE Mary Jane 15000

success

$ PAY 100000 100001 10

success

$ PAY 100000 100001 20

success

$ PAY 100001 100000 30

success

$ LIST TRANSACTIONS

1: 100000 -> 100001 | $10 | 1128448214

2: 100000 -> 100001 | $20 | 919049074

3: 100001 -> 100000 | $30 | 755697066

$ ARCHIVE ledger.txt accounts.txt

success

$ PAY 100001 100000 50

success

$ CREATE Andrew Perry

success

$ RECOVER ledger.txt accounts.txt

success

$ LIST TRANSACTIONS

1: 100000 -> 100001 | $10 | 1128448214

2: 100000 -> 100001 | $20 | 919049074

3: 100001 -> 100000 | $30 | 755697066

$ LIST ACCOUNTS

100000

100001

$ EXIT

bye

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Examples (5)

$ RECOVER bad_hash.txt accounts.txt

invalid ledger

$ CREATE John Smith

success

$ CREATE Amy Adams 0

success

$ PAY 100000 100001 10000

success

$ PAY 100001 100000 10

success

$ CANCEL 1

insufficient funds

$ RECOVER bad_ledger.txt accounts.txt

no such file

$ EXIT

bye

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Examples (6)

$ CREATE John Smith

success

$ CREATE Mary Jane 15000

success

$ CREATE Andrew Perry

success

$ PAY 100000 100001 30

success

$ MAX

$15030

$ MIN

$9970

$ MEAN

$11666

$ MEDIAN

$10000

$ TOTAL

$35000

$ MERGE 100000 100001 100002

success

$ LIST ACCOUNTS

100000

100001

100002

$ BALANCE 100000

$35000

$ EXIT

bye

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Writing your own testcases

We have provided you with some test cases but these do not test all the functionality described in the 

assignment. It is important that you thoroughly test your code by writing your own test cases.

You should place all of your test cases in the tests/ directory. Ensure that each test case has the .in input file 

along with a corresponding .out output file. We require that the names of your test cases are descriptive so 

that you know what each is testing, e.g. history.in & history.out and we can accurately and quickly assess 

your test cases. Note: If you do not format your test case files as explained (where each test case has 

Submission Details

Final deliverable for the correctness and manual inspection will be due on the 10th of April at midnight.

You must submit your code and tests using the assignment page on Ed. To submit, simply place your files and 

folders into the workspace, click run to check your program works and then click submit.

You are encouraged to submit multiple times, but only your last submission will be considered.

Marking

You will only be given valid inputs as part of the automatic test suite. Your program will be checked for errors 

that a user can possibly make. In addition, we will mark your program against a substantial collection of 

hidden test cases.

3 marks are assigned based on automatic tests for the correctness of your program. This component will use 

hidden test cases that cover every aspect of the specification. Your program must match the exact output in 

the examples and the test cases on Ed. 

3 marks are assigned based on a manual inspection of the style (1 mark) and tests cases (2 marks). Make sure 

that you carefully follow the assignment specifications and thoroughly test your code, optimising for 

coverage and testing for a variety of input ranges. Style will be assessed based on the conventions set out in 

the Google Java Style Guide (https://google.github.io/styleguide/javaguide.html)

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Academic declaration

By submitting this assignment you declare the following:

I declare that I have read and understood the University of Sydney Student Plagiarism: Coursework Policy and Procedure, and except where specifically 

acknowledged, the work contained in this assignment/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 Student Plagiarism: Coursework Policy and Procedure 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 acknowledgment 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 Computer Science, 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 of the 

assignment may be maintained by the service or the School of Computer Science for the purpose of future plagiarism checking.