// Ilustrates the use of two iterators that implement the an interface called SIterator
// (there is an Iterator interface with the same funtionality in the Java library)

public class StringIteratorProblem

{

public static void main(String[] args)

{

String movie = "Software Engineering, it is great";

StringIterator iter1 = new StringIterator(movie);

printWithSpaces(iter1);

StringIterator2 iter2 = new StringIterator2(movie);

printWithSpaces(iter2);

}

public static void printWithSpaces(SIterator iter)

{

for (; iter.hasMoreElements(); iter.nextElement())

{

System.out.print(iter.value() + " ");

}

System.out.println();

}

}

public interface SIterator

{

public boolean hasMoreElements();

public Object nextElement();

public void reset();

public Object value();

}

class StringIterator implements SIterator

{

String string;

int index;

StringIterator(String s) { string = s; index = 0; }

public boolean hasMoreElements() { return index < string.length(); }

public Object nextElement()

{

char temp = string.charAt(index);

index++;

return new Character(temp);

}

public void reset() { index = 0; }

public Object value()

{

char temp = string.charAt(index);

return new Character(temp);

}

}

class StringIterator2 implements SIterator

{

String string;

int index;

StringIterator2(String s) { string = s; index = 0; }

public boolean hasMoreElements() { return index < string.length(); }

public Object nextElement()

{

char temp = string.charAt(index);

index = index + 2;

return new Character(temp);

}

public void reset() { index = 0; }

public Object value()

{

char temp = string.charAt(index);

return new Character(temp);

}

}

Output:

S o f t w a r e E n g i n e e r i n g , i t i s g r e a t

S f w r n i e r n , i s g e t