CSc:Software Design Laboratory Assignment 3-Solution

Description

In this assignment we will expand on your Java programming skills by implementing multiple classes with different features.

You will rely on Java’s library for certain tasks and design each class to maximum reusability with fewer lines of code.

Note: please do your own work, sharing and/or copying code and/or solution ideas with/from others will result in a grade of 0 and disciplinary actions for all involved parties. If you run into any problems and have done your best to solve them, please see me before/after class or e-mail me.

Problem Description:

Implement the classes shown in the class diagram below ( Figure 1). Please adhere to the names shown in the diagram. The classes are self-explanatory; however, note the following:

Class LogEntry :

• Non-default constructor: throws an IllegalArgumentException if one of the following is true:

• 1. Id is not a valid numeric string. Numeric strings are strings consisting of numbers ONLY.

  2. timestamp, source, destination, protocol, length, description: cannot be empty or null

• toString: this method returns a comma-delimited string of all the class’ variables. i.e. the values of

id, timestamp, source, destination, protocol, length, description

Class NetworkLogManager :

• loadFile: reads records from the provided text file (Network.log). Refer to the section below for the file’s structure. Valid records should be added to listLogEntries. This method should handle Exceptions from the class LogEntry by printing the message Skipping line: followed by the skipped line. There are 147 invalid records (see Figure 2).

Hints:

• • Use Scanner class to read the input file’s lines. This is similar to reading from the standard command prompt.

  • Use the String class’ split method to parse each line.

• toString: this method returns the string shown next. Replace ?? with the number of entries in listLogEntries.

NetworkLogManager: there are ?? records

• searchByRange: returns a list of records between the provided dates (inclusive). You will need to convert the String parameters to type Date in order to perform the search. To do this, use the SimpleDateFormat class with pattern “MMM dd yyy HH:mm:ss”.

• searchBy: the remaining 7 required methods allow searching by a specific field. It is inefficient to implement each one independently, therefore you should create a private common method which contains the search logic. This method should select the proper field. One way to do this is to create an internal enumerator and use a switch structure.

Class A3Driver :

• This is the provided test class. Your code should work with this class AS IS. Please DO NOT modify this class and adhere to the names provided in the class diagram (Figure 1)

• Your code’s output should match the output shown in Figure 3.

Input file’s format:

• The file contains 501 comma‐delimited rows.

• Each row consists of 7 columns (id, timestamp, source, destination, protocol, length, description).

• Some columns contain invalid values. Valid rows have ID and LENGTH that is NOT 0. All columns should have values (i.e. cannot be empty). If either column contains an invalid value, the entire column is rejected. There are 74 invalid rows (Figure 2).

Grades:

Item	Points
Class LogEntry
Constructor	10
Getters/setters	5
Class NetworkLogManager
Constructor	5
loadFile	10
toString	5
searchByRange	15
7 searchBy methods	20
Common method for 7 searchBy methods	20
Correct output	10
	100

The City College of New York

Department of Compute Science

CSc 221: Software Design Laboratory