搜索引擎信息搜索，搜索引擎信息搜索什么意思

在Java中，我们可以使用Lucene库来实现搜索引擎信息搜索功能，以下是使用Lucene实现索引管理、查询解析和查询处理的示例代码：

import org.apache.lucene.analysis.Analyzer;
import org.apache.lucene.analysis.standard.StandardAnalyzer;
import org.apache.lucene.document.Document;
import org.apache.lucene.document.Field;
import org.apache.lucene.document.TextField;
import org.apache.lucene.index.IndexWriter;
import org.apache.lucene.index.IndexWriterConfig;
import org.apache.lucene.store.Directory;
import org.apache.lucene.store.RAMDirectory;
import org.apache.lucene.util.Version;
import java.io.IOException;
import java.util.HashMap;
import java.util.Map;
import java.util.regex.Pattern;
import java.util.stream.Collectors;
import java.util.stream.Stream;
public class IndexManager extends Thread {
  private static final Pattern PATTERN = PatternSyntaxException.class;
  private static final Version VERSION = new Version("7.10");
  private Directory indexDirectory;
  private Analyzer analyzer;
  private Map<String, Integer> keywordIndices;
  private boolean isRunning = true;
  public IndexManager() throws IOException {
    indexDirectory = new RAMDirectory();
    analyzer = new StandardAnalyzer();
  }
  public void createIndex(String content) throws IOException {
    Document document = new Document();
    for (String word : content.split("\\s+")) {
      int index = keywordIndices == null || keywordIndices.getOrDefault(word, -1) < 0 ? keywordIndices.size() : keywordIndices.getOrDefault(word, -1);
      Field field = new Field("content", word, Field.Store.YES, Field.Index.ANALYZED);
      field.setTokenized(true);
      field.setStored(true);
      field.setOmitNorms(true);
      int boost = Math.max(1, index * 2);
      field = new Field("keyword", word, Field.Store.NO, Field.Index.ANALYZED, boost);
      document.add(field);
    }
    IndexWriterConfig config = new IndexWriterConfig(analyzer);
    config.setOpenMode(IndexWriterConfig.OpenMode.CREATE_OR_APPEND);
    IndexWriter writer = new IndexWriter(indexDirectory, config);
    writer.addDocument(document);
    writer.close();
  }
  public void updateKeywordIndices() throws Exception {
    HashMap<String, Integer> newKeywordIndices = new HashMap<>();
    int maxKeywordIndex = Collections.max(keywordIndices.values());
    int maxContentIndex = Collections.max(keywordIndicesByContent().values());
    int currentIndex = maxKeywordIndex + maxContentIndex + 1;
    int minIndex = Math.min(maxKeywordIndex, maxContentIndex) + 1;
    int maxIndex = Math.max(maxKeywordIndex, maxContentIndex) + currentIndex;
    int[] indices = new int[currentIndex];
    int[] counts = new int[currentIndex];
    int[] offsets = new int[currentIndex];
    int i = minIndex;
    int j = minIndex;
    int k = minIndex;
    int count = minIndex;
    int offset = minIndex;
    int[] contentIndices = keywordIndicesByContent().values().stream().mapToInt(Integer::intValue).toArray();
    int[] keywordIndicesByContentCopy = keywordIndicesByContent().values().toArray(); // 避免原数组被修改时影响后续计算结果
    Arrays