How can I parse a string for a set?

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So I am writing a method that is supposed to take an input String of the format "s1:{1,2,3,4}" and put it into a set. The set class I have developed myself and is as follows:

public class Set<E> implements Iterable<E> {
private static final int DEFAULT_CAPACITY = 20;

private String name;

private E[] theData;

private int size = 0;

private int capacity = 0;


public Set(){
    capacity = DEFAULT_CAPACITY;
    theData = (E[]) new Object[capacity];
}//end constructor

public Set(String name){
    capacity = DEFAULT_CAPACITY;
    theData = (E[]) new Object[capacity];
    this.name = name;
}//end constructor

public String getName(){
    return name;
}//end getName

public void setName(String name){
    this.name = name;
}//end setName

//adds object to set
public void add(Object E){
    if (size == capacity){
        reallocate();
    }//end if
    theData[size] = (E) E;
    size++;
    for (int j = 0; j<size; j++){
        for (int k = 0; k < size; k++){
            if ((int)theData[j] < (int)theData[k]){
                E temp = theData[j];
                theData[j] = theData[k];
                theData[k] = temp; 
            }//end if
        }//end nested for loop
    }//end for loop
    int counter = 0;
    for (int i = 0; i < size; i++){
         if (E == theData[i]){
             counter++;
             if (counter >= 2){
                remove((Object)E);
             }//end nested if
         }//end if
    }//end for loop
}//end add method

public E get(int i){
    if (i < 0 || i >= size){
        throw new ArrayIndexOutOfBoundsException(i);
    }//end if
    else{
    return theData[i];
    }//end else 
}//end get method

public E remove(int i){
    if (i < 0 || i >= size){
        throw new ArrayIndexOutOfBoundsException(i);
    }//end if
    E returnValue = theData[i];
    for (int j = i + 1; j < size; j++){
        theData[j - 1] = theData[j];
    }//end for loop
    size--;
    return returnValue;
}//end remove method

public void remove(Object E){
    for (int i = 0; i < size; i++){
        if (E == theData[i]){
            for (int j = i + 1; j < size; j++){
                theData[j - 1] = theData[j];
            }//end nested for loop
            size--;
        }//end if
    }//end for loop
}//end remove method

//fix!
public int find(Object E){
    int first, last, middle;
    first = 0;
    last = size - 1;
    middle = (first+last) / 2;
    while( first <= last ){
      if ((int)theData[middle] > (int)E ){
        last = middle - 1;    
      }//end if
      else if ((int)theData[middle] < (int)E ){
        first = middle + 1;
      }//end else if
      else{
          return middle;
      }//end else
   }//end while
    if (first > last){
           return -1;
     }//end if
    return -1;


 }//end find method

public Set<E> union(Set<E> s){
    Set<E> returnSet = new Set<E>();
    for (int i = 0; i < this.size; i++){
        returnSet.add(this.theData[i]);
        }//end for loop
    for (int i = 0; i < s.size; i++){
        returnSet.add(s.theData[i]);
        }//end for loop
    return returnSet;
}//end union method

public Set<E> intersect(Set<E> s){
    Set<E> returnSet = new Set<E>();
    for (int i = 0; i < this.size; i++){
        for (int j = 0; j < s.size; j++){
            if (this.theData[i] == s.theData[j]){
                returnSet.add(theData[i]);
            }//end if
        }//end nested for loop
    }//end for loop
    return returnSet;
}//end intersect method

public Set<E> subtract(Set<E> s){
    Set<E> returnSet = new Set<E>();
    for (int i = 0; i < this.size; i++){
        for (int j = 0; j < s.size; j++){
            if (this.theData[i] == s.theData[j]){
                this.remove((Object)this.theData[i]);
                s.remove((Object)s.theData[j]);
            }//end if
        }//end nested for loop
    }//end for loop
    for (int i = 0; i < this.size; i++){
        returnSet.add(this.theData[i]);
    }//end for loop
    for (int i = 0; i < s.size; i++){
        returnSet.add(s.theData[i]);
    }//end for loop
    return returnSet;
}
//end subtract method
public boolean equals(Set<E> s){
    boolean result = false;
    for (int i = 0; i < this.size; i++){
        if (this.theData[i] == s.theData[i]){
            result = true;
        }//end if
        if (this.theData[i] != s.theData[i]){
            result = false;
            break;
        }//end if
    }//end for loop
    return result;
}//end equals method


private void reallocate(){
    capacity = 2*capacity;
    theData = Arrays.copyOf(theData,  capacity);
}//end reallocate method

public String toString(){
    StringBuilder set = new StringBuilder();
    set.append("{");
    for (int i = 0; i < size; i++){
        set.append(theData[i]);
        if (i != size-1){
            set.append(",");
        }//end if
    }//end for loop
    set.append("}");
    return set.toString();
}//end toString()

public SetIterator<E> iterator() {
    SetIterator<E> it = new SetIterator<E>() {

        private int currentIndex = 0;


        public boolean hasNext() {
            if (currentIndex < size && theData[currentIndex] != null){
                currentIndex++;
                return true;
            }//end if
            else{
                return false;
            }//end else
        }//end hasNext()


        public E next() {
            if (!hasNext()) {
                throw new NoSuchElementException();
            }//end if
            return theData[currentIndex++];
        }//end next()


        public boolean hasPrevious() {
            if (currentIndex <= size && currentIndex > 0){
                currentIndex--;
                return true;
            }//end if
            else{
                return false;
            }//end else
        }//end hasPrevious()


        public E previous() {
            if (!hasPrevious()) {
                throw new NoSuchElementException();
            }//end if
            return theData[currentIndex--];
        }//end previous()


        public void add(E item) {
            theData[currentIndex-1] = item;
        }//end add()


        public void remove() {
            for (int i = 0; i < size; i++){
                if (theData[currentIndex] == theData[i]){
                    for (int j = i + 1; j < size; j++){
                        theData[j - 1] = theData[j];
                    }//end nested for loop
                    size--;
                }//end if
            }//end for loop
        }//end remove()

    };//end new SetIterator()
    return it;

}//end iterator method

}//end Set class

Also, the method is supposed to throw an exception if the method has invalid format such as s1:[1 2,3,4} this example being the missing comma and curly brace. Also the input may have any number of whitespaces and will still be considered valid an example being s1: {1, 2, 3, 4 }. So far all I have for the method is:

public Set<Integer> parse(String input){
    String s[] = input.split(":");
    String name = s[0];
    Set<Integer> returnSet = new Set<Integer>(name);




    return returnSet;
}

I am not sure how to properly get the elements out of the set in the string and put them into a Set object. I know I can parseInt once I get them by themselves but I am having trouble isolating each element. Also, there is no limit on how many elements a set can have which means my code has to work for any number of elements. I have also considered regular expressions but I feel as if there is a more efficient way of doing this that I am overlooking. Any help will be appreciated.

asked 2 mins ago

user3554599

7

How can I parse a string for a set?