Question

This file that has the outline of an iterator which will be used to return each char within a String. Complete the hasNext() and next() methods to enable this iteration. In case it is of use, String has two methods which may provide useful -- size() (returning the number of chars it contains) and charAt() (returning the character at the location passed as an argument).

import java.util.Iterator;
import java.util.NoSuchElementException;

public class CharacterIterator implements Iterator<Character> {
  /** The String whose characters will be returned by this Iterator. */
  private String characterSource;

  /** The next character in the String which will be returned by the Iterator. */
  private int cursor;

  /**
   * Create a new Iterator which can be used to go through the characters in this String.
   *
   * @param str Source of characters over which we will be iterating.
   */
  public CharacterIterator(String str) {
    cursor = 0;
    characterSource = str;
  }

  /** Returns whether the iterator has a next object. */
  public boolean hasNext() {

  }

  /** Returns the next object in the iterator. */
  public Character next() throws NoSuchElementException {

  }

  public void remove() {
    throw new UnsupportedOperationException();
  }
}

Answer 1

Here are the two methods filled for you:

import java.util.Iterator;
import java.util.NoSuchElementException;

public class CharacterIterator implements Iterator<Character> {
/** The String whose characters will be returned by this Iterator. */
private String characterSource;

/** The next character in the String which will be returned by the Iterator. */
private int cursor;

/**
* Create a new Iterator which can be used to go through the characters in this String.
*
* @param str Source of characters over which we will be iterating.
*/
public CharacterIterator(String str) {
cursor = 0;
characterSource = str;
}

/** Returns whether the iterator has a next object. */
public boolean hasNext() {
   return cursor < characterSource.length();
}

/** Returns the next object in the iterator. */
public Character next() throws NoSuchElementException {
   cursor++;
   return characterSource.charAt(cursor-1);
}

public void remove() {
throw new UnsupportedOperationException();
}
}