Question

Class StringImproved

public class StringImproved extends java.lang.Object

This program replaces the string class with a mutable string.

This class represents a character array and provide functionalities need to do basic string processing. It contains an array of characters, representing a textual string.

Overview

In Java, Strings are a great device for storing arrays of characters. One limitation of Strings in Java, however (there is always at least one), is that they are immutable (ie. they cannot be changed once created). Your mission is to create a mutable String Class (called StringImproved) with some clever features. You will also need to ensure that your program is bug free. Your StringImproved Class should be uncrashable as possible. If your code detects faulty/incorrect input it should handle it as instructed in this java API

Data Structure

To make your life easier you will be provided with an API specification (just like the JavaDocs you use for your programming). You must use a char array to store your String in your Class. You are not permitted to use any collection Classes in this assignment. You will need to implement the entire class based on the API specification. This class will encapsulate all the functionality required.

Testing

A test program is also provided for you to use. Please read it carefully as you will be expected to generate your own in assignment 2. Use the test driver as a starting point to test your Class as thoroughly as possible. Note that the marker reserves the right to test more conditions if they think of them.

How to Do The Assignment

I suggest you do your assignment in the following order

Create all the method signatures in the StringImproved Class. Each method should just be blank (with a return null or -1 if necessary).

Compile and make sure that the program works (well, technically it won't because the methods are empty, but make sure it compiles with no error).

Write the constructors. Test.

Write the length method. Test.

Write the charAt method. Test.

Write the endsWith method. Test.

Write the toLowerCase method. Test.

Write the toUpperCase method. Test.

Write the lastIndexOf method. Test.

Write the increaseArray method. Test (note there is no provided test you will need to do it). Write the shrinkArray method. Test (note there is no provided test you will need to do it). Write the contains method. Test.

Write the substring method. Test.

Write the insert method. Test.

Write the append method. Test.

Write the deleteSubString int int method. Test.

Write the deleteSubString string method. Test.

Write the deleteCharAt method. Test. Write the prepend method. Test.

Write the replaceString method. Test.

Write the sort (advanced students) method. Test.

Note that when you add functionality you may have to add test scenarios to other test methods to ensure you have covered all the possibilities.

Additional Requirement.

In addition to what is above there are a number of requirements for this assignment. Most of these are to introduce interesting problems for you to solve and must be obeyed.

As you are programming you will also need to comment your code thoroughly in each of your methods.

Whenever you use a String class (for example passed as a parameter) you can only use the charAt() method of String to get content. Sorry we can't make this too easy. The char array in your structure must always have only the space that is required.

You are not permitted to use any String methods in this class. If you use a String method you will get zero for the offending method. There is one exception you are permitted to use the Strings toCharArray method

Answer 1

Here is the complete prototype of the StringImproved.java class

__________________________________________________________________________________________

public class StringImproved {

    private char[] stringArray;

    //Write the constructors
    public StringImproved() {
        stringArray = null;
    }

    //Write the constructors
    public StringImproved(String aString) {
        stringArray = aString.toCharArray();
    }

    //Write the constructors
    public StringImproved(char[] stringArray) {
        this.stringArray = stringArray;
    }

    //Write the length method
    public int length() {
        return -1;
    }

    //Write the charAt method
    public char charAt(int index) {
        return '\0';
    }

    //Write the endsWith method
    public char endsWith() {
        return '\0';
    }

    //Write the toLowerCase method
    public void toLowerCase() {

    }

    //Write the toUpperCase method.a
    public void toUpperCase() {

    }

    //Write the lastIndexOf method
    public int lastIndexOf(char c) {
        return -1;
    }

    //Write the increaseArray method
    public void increaseArray() {

    }

    //Write the shrinkArray method
    public void shrinkArray() {

    }

    //Write the substring method
    public String substring(int begin, int end) {
        return "";
    }

    //Write the substring method
    public String substring(int begin) {
        return "";
    }

    //Write the insert method
    public void insert(int index, char c) {

    }

    //Write the append method
    public void append(char c) {

    }

    //Write the deleteSubString string method
    public void deleteSubString(String substring) {

    }

    //Write the deleteSubString int int method
    public void deleteSubString(int begin, int end) {

    }

    //Write the deleteCharAt
    public void deleteCharAt(int index) {

    }

    //prepend method.
    public void prepend(char c) {

    }

    //Write the replaceString method
    public void replaceString(String search, String replace) {

    }

    //Write the sort (advanced students) method
    public void sort() {

    }


}