common_helper/src/main/java/com/xiongyingqi/util/CompositeIterator.java
public void add(Iterator<E> iterator) {
        Assert.state(!inUse, "You can no longer add iterator to a composite iterator that's already in use");
        if (iterators.contains(iterator)) {
            throw new IllegalArgumentException("You cannot add the same iterator twice");
        }
        iterators.add(iterator);
    }
public void add(Iterator<E> iterator) {
        Assert.state(!inUse, "You can no longer add iterator to a composite iterator that's already in use");
        if (iterators.contains(iterator)) {
            throw new IllegalArgumentException("You cannot add the same iterator twice");
        }
        iterators.add(iterator);
    }
public void add ( Iterator < E > iterator ) { Assert . state ( ! inUse , "You can no longer add iterator to a composite iterator that's already in use" ) ; if ( iterators . contains ( iterator ) ) { throw new IllegalArgumentException ( "You cannot add the same iterator twice" ) ; } iterators . add ( iterator ) ; }
Add given iterator to this composite.
Add given iterator to this composite .