gobblin.ingestion.google.webmaster.UrlTriePrefixGrouper.java Source code

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Here is the source code for gobblin.ingestion.google.webmaster.UrlTriePrefixGrouper.java

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/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package gobblin.ingestion.google.webmaster;

import java.util.ArrayList;
import java.util.Iterator;
import java.util.NoSuchElementException;

import org.apache.commons.lang3.tuple.Pair;
import org.apache.commons.lang3.tuple.Triple;

public class UrlTriePrefixGrouper implements UrlGrouper {

    private final int _groupSize;
    private final UrlTrie _trie;
    private final Iterator<Pair<String, UrlTrieNode>> _iterator;
    private Triple<String, GoogleWebmasterFilter.FilterOperator, UrlTrieNode> _retVal;

    public UrlTriePrefixGrouper(UrlTrie trie, int groupSize) {
        _trie = trie;
        _groupSize = groupSize;
        _iterator = new UrlTriePostOrderIterator(trie, groupSize);
    }

    @Override
    public boolean hasNext() {
        if (_retVal != null) {
            return true;
        }

        while (_iterator.hasNext() && _retVal == null) {
            Pair<String, UrlTrieNode> nextPair = _iterator.next();
            UrlTrieNode nextNode = nextPair.getRight();
            if (nextNode.getSize() <= _groupSize) {
                _retVal = Triple.of(nextPair.getLeft(), GoogleWebmasterFilter.FilterOperator.CONTAINS, nextNode);
                return true;
            } else if (nextNode.isExist()) {
                _retVal = Triple.of(nextPair.getLeft(), GoogleWebmasterFilter.FilterOperator.EQUALS, nextNode);
                return true;
            }
        }
        return false;
    }

    @Override
    public Triple<String, GoogleWebmasterFilter.FilterOperator, UrlTrieNode> next() {
        if (hasNext()) {
            Triple<String, GoogleWebmasterFilter.FilterOperator, UrlTrieNode> retVal = _retVal;
            _retVal = null;
            return retVal;
        }
        throw new NoSuchElementException();
    }

    public UrlTrie getTrie() {
        return _trie;
    }

    /**
     * Get the detailed pages under this group
     */
    public static ArrayList<String> groupToPages(
            Triple<String, GoogleWebmasterFilter.FilterOperator, UrlTrieNode> group) {
        ArrayList<String> ret = new ArrayList<>();
        if (group.getMiddle().equals(GoogleWebmasterFilter.FilterOperator.EQUALS)) {
            if (group.getRight().isExist()) {
                ret.add(group.getLeft());
            }
        } else if (group.getMiddle().equals(GoogleWebmasterFilter.FilterOperator.CONTAINS)) {
            UrlTrie trie = new UrlTrie(group.getLeft(), group.getRight());
            Iterator<Pair<String, UrlTrieNode>> iterator = new UrlTriePostOrderIterator(trie, 1);
            while (iterator.hasNext()) {
                Pair<String, UrlTrieNode> next = iterator.next();
                if (next.getRight().isExist()) {
                    ret.add(next.getLeft());
                }
            }
        }
        return ret;
    }

    @Override
    public void remove() {
        throw new UnsupportedOperationException();
    }

    @Override
    public int getGroupSize() {
        return _groupSize;
    }
}