Example usage for org.apache.lucene.search DocIdSetIterator nextDoc

Introduction

In this page you can find the example usage for org.apache.lucene.search DocIdSetIterator nextDoc.

Prototype

public abstract int nextDoc() throws IOException;

Source Link

Document

Advances to the next document in the set and returns the doc it is currently on, or #NO_MORE_DOCS if there are no more docs in the set.
NOTE: after the iterator has exhausted you should not call this method, as it may result in unpredicted behavior.

Usage

From source file:lucene.security.search.DocumentVisibilityFilter.java

License:Apache License

public static DocIdSet getLogicalOr(final List<DocIdSet> list) throws IOException {
    if (list.size() == 0) {
        return DocIdSet.EMPTY_DOCIDSET;
    }//w  w  w.  ja v a2 s. co m
    if (list.size() == 1) {
        DocIdSet docIdSet = list.get(0);
        Bits bits = docIdSet.bits();
        if (bits == null) {
            throw new IOException("Bits are not allowed to be null for DocIdSet [" + docIdSet + "].");
        }
        return docIdSet;
    }
    int index = 0;
    final Bits[] bitsArray = new Bits[list.size()];
    int length = -1;
    for (DocIdSet docIdSet : list) {
        Bits bits = docIdSet.bits();
        if (bits == null) {
            throw new IOException("Bits are not allowed to be null for DocIdSet [" + docIdSet + "].");
        }
        bitsArray[index] = bits;
        index++;
        if (length < 0) {
            length = bits.length();
        } else if (length != bits.length()) {
            throw new IOException(
                    "Bits length need to be the same [" + length + "] and [" + bits.length() + "]");
        }
    }
    final int len = length;
    return new DocIdSet() {

        @Override
        public Bits bits() throws IOException {
            return new Bits() {

                @Override
                public boolean get(int index) {
                    for (int i = 0; i < bitsArray.length; i++) {
                        if (bitsArray[i].get(index)) {
                            return true;
                        }
                    }
                    return false;
                }

                @Override
                public int length() {
                    return len;
                }

            };
        }

        @Override
        public boolean isCacheable() {
            return true;
        }

        @Override
        public DocIdSetIterator iterator() throws IOException {
            final DocIdSetIterator[] docIdSetIteratorArray = new DocIdSetIterator[list.size()];
            long c = 0;
            int index = 0;
            for (DocIdSet docIdSet : list) {
                DocIdSetIterator iterator = docIdSet.iterator();
                iterator.nextDoc();
                docIdSetIteratorArray[index] = iterator;
                c += iterator.cost();
                index++;
            }
            final long cost = c;
            return new DocIdSetIterator() {

                private int _docId = -1;

                @Override
                public int advance(int target) throws IOException {
                    callAdvanceOnAllThatAreBehind(target);
                    Arrays.sort(docIdSetIteratorArray, COMPARATOR);
                    DocIdSetIterator iterator = docIdSetIteratorArray[0];
                    return _docId = iterator.docID();
                }

                private void callAdvanceOnAllThatAreBehind(int target) throws IOException {
                    for (int i = 0; i < docIdSetIteratorArray.length; i++) {
                        DocIdSetIterator iterator = docIdSetIteratorArray[i];
                        if (iterator.docID() < target) {
                            iterator.advance(target);
                        }
                    }
                }

                @Override
                public int nextDoc() throws IOException {
                    return advance(_docId + 1);
                }

                @Override
                public int docID() {
                    return _docId;
                }

                @Override
                public long cost() {
                    return cost;
                }

            };
        }
    };
}

From source file:lux.functions.Count.java