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Intelie Pipes' API classes and interfaces
package net.intelie.pipes.util;
import java.io.Serializable;
import java.util.Arrays;
import java.util.Iterator;
import java.util.NoSuchElementException;
public class ConcatIterable implements Iterable, Serializable {
private static final long serialVersionUID = 1L;
private final Iterable> iterables;
public ConcatIterable(Iterable> iterables) {
this.iterables = iterables;
}
public static ConcatIterable create(Iterable... iterables) {
return new ConcatIterable(Arrays.asList(iterables));
}
@Override
public Iterator iterator() {
return new ConcatIterator();
}
@Override
public String toString() {
return "(" + Iterables.join(" ++ ", iterables) + ")";
}
private class ConcatIterator implements Iterator, Serializable {
private static final long serialVersionUID = 1L;
private final Iterator> parent;
private Iterator current;
public ConcatIterator() {
parent = iterables.iterator();
current = null;
}
@Override
public boolean hasNext() {
if (currentHasNext())
return true;
while (parent.hasNext() && !currentHasNext()) {
Iterable next = parent.next();
if (next != null)
current = next.iterator();
}
return currentHasNext();
}
private boolean currentHasNext() {
return current != null && current.hasNext();
}
@Override
public T next() {
if (!hasNext())
throw new NoSuchElementException();
return current.next();
}
}
}