private static class Collections2.PermutationIterator<E> extends AbstractIterator<java.util.List<E>>
| Modifier and Type | Field and Description |
|---|---|
(package private) int[] |
c |
(package private) int |
j |
(package private) java.util.List<E> |
list |
(package private) int[] |
o |
| Constructor and Description |
|---|
PermutationIterator(java.util.List<E> list) |
| Modifier and Type | Method and Description |
|---|---|
(package private) void |
calculateNextPermutation() |
protected java.util.List<E> |
computeNext()
Returns the next element.
|
(package private) void |
switchDirection() |
endOfData, hasNext, next, peekremovefinal java.util.List<E> list
final int[] c
final int[] o
int j
PermutationIterator(java.util.List<E> list)
protected java.util.List<E> computeNext()
AbstractIteratorAbstractIterator.endOfData() when there are no elements left in the iteration. Failure to
do so could result in an infinite loop.
The initial invocation of AbstractIterator.hasNext() or AbstractIterator.next() calls
this method, as does the first invocation of hasNext or next following each successful call to next. Once the
implementation either invokes endOfData or throws an exception,
computeNext is guaranteed to never be called again.
If this method throws an exception, it will propagate outward to the
hasNext or next invocation that invoked this method. Any
further attempts to use the iterator will result in an IllegalStateException.
The implementation of this method may not invoke the hasNext,
next, or AbstractIterator.peek() methods on this instance; if it does, an
IllegalStateException will result.
computeNext in class AbstractIterator<java.util.List<E>>endOfData was called
during execution, the return value will be ignored.void calculateNextPermutation()
void switchDirection()