101 lines
3.3 KiB
Java
101 lines
3.3 KiB
Java
|
/*
|
||
|
|
The contents of this file are subject to the THDL Open Community License
|
||
|
|
Version 1.0 (the "License"); you may not use this file except in compliance
|
||
|
|
with the License. You may obtain a copy of the License on the THDL web site
|
||
|
|
(http://www.thdl.org/).
|
||
|
|
|
||
|
|
Software distributed under the License is distributed on an "AS IS" basis,
|
||
|
|
WITHOUT WARRANTY OF ANY KIND, either express or implied. See the
|
||
|
|
License for the specific terms governing rights and limitations under the
|
||
|
|
License.
|
||
|
|
|
||
|
|
The Initial Developer of this software is the Tibetan and Himalayan Digital
|
||
|
|
Library (THDL). Portions created by the THDL are Copyright 2003 THDL.
|
||
|
|
All Rights Reserved.
|
||
|
|
|
||
|
|
Contributor(s): ______________________________________.
|
||
|
|
*/
|
||
|
|
|
||
|
|
package org.thdl.tib.text.ttt;
|
||
|
|
|
||
|
|
import java.util.ListIterator;
|
||
|
|
import java.util.NoSuchElementException;
|
||
|
|
import java.util.ArrayList;
|
||
|
|
|
||
|
|
/** An object that can iterate over an {@link #TParseTree}.
|
||
|
|
*
|
||
|
|
* @author David Chandler */
|
||
|
|
class ParseIterator {
|
||
|
|
private ArrayList al = null;
|
||
|
|
private int sz;
|
||
|
|
private ListIterator[] iterators;
|
||
|
|
private boolean first = true;
|
||
|
|
private boolean hasNextParse = true;
|
||
|
|
/** Constructs a new ParseIterator that iterates over a list of
|
||
|
|
* TStackListLists. */
|
||
|
|
ParseIterator(ArrayList al) {
|
||
|
|
this.al = al;
|
||
|
|
sz = al.size();
|
||
|
|
iterators = new ListIterator[sz];
|
||
|
|
hasNextParse = false;
|
||
|
|
for (int i = 0; i < sz; i++) {
|
||
|
|
iterators[i] = ((TStackListList)al.get(i)).listIterator();
|
||
|
|
if (iterators[i].hasNext())
|
||
|
|
hasNextParse = true;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
/** Returns true if and only if there is another parse
|
||
|
|
* available. */
|
||
|
|
boolean hasNext() {
|
||
|
|
return hasNextParse;
|
||
|
|
}
|
||
|
|
|
||
|
|
/** Returns the next available parse. */
|
||
|
|
TStackList next() {
|
||
|
|
if (!hasNextParse)
|
||
|
|
throw new NoSuchElementException("no parses left");
|
||
|
|
if (first) {
|
||
|
|
first = false;
|
||
|
|
TStackList x = new TStackList();
|
||
|
|
for (int i = 0; i < sz; i++) {
|
||
|
|
TStackList nextSL = (TStackList)iterators[i].next();
|
||
|
|
x.addAll(nextSL);
|
||
|
|
}
|
||
|
|
|
||
|
|
// The next guy is found by taking the previous item of
|
||
|
|
// each iterator.
|
||
|
|
hasNextParse = false;
|
||
|
|
for (int i = sz - 1; i >= 0; i--) {
|
||
|
|
if (iterators[i].hasNext()) {
|
||
|
|
iterators[i].next();
|
||
|
|
hasNextParse = true;
|
||
|
|
break;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
return x;
|
||
|
|
}
|
||
|
|
|
||
|
|
// Up the rightmost iterator you can. If you can, reset all
|
||
|
|
// guys to the right of it. If you can't, we're done.
|
||
|
|
TStackList x = new TStackList(sz);
|
||
|
|
hasNextParse = false;
|
||
|
|
for (int i = sz - 1; i >= 0; i--) {
|
||
|
|
TStackList prevSL = (TStackList)iterators[i].previous();
|
||
|
|
x.addAll(0, prevSL);
|
||
|
|
iterators[i].next();
|
||
|
|
if (!hasNextParse && iterators[i].hasNext()) {
|
||
|
|
hasNextParse = true;
|
||
|
|
iterators[i].next();
|
||
|
|
// Reset all iterators to the right of i.
|
||
|
|
for (int j = i + 1; j < sz; j++) {
|
||
|
|
while (iterators[j].hasPrevious())
|
||
|
|
iterators[j].previous();
|
||
|
|
iterators[j].next();
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
return x;
|
||
|
|
}
|
||
|
|
}
|