lucene series 1 document 文档 索引创建

此图为lucene 获取数据建立索引  Understanding the indexing process

lucene 建立索引步骤

1，Extracting text and creating the document   提取数据，创建文档

2，Analysis         分析获取的内容，采用分词 过滤stop word（非关键字）

3，add  to the index  添加分析后的结果到 index

在此步 把索引分块存储，为了检索给力，这就是为什么lucene index中为啥有那么多小文件的原因吧

代码提现：

 protected String[] ids = {"1", "2"};
  protected String[] unindexed = {"Netherlands", "Italy"};
  protected String[] unstored = {"Amsterdam has lots of bridges",
                                 "Venice has lots of canals"};
  protected String[] text = {"Amsterdam", "Venice"};
  private Directory directory;
  protected void setUp() throws Exception {
    directory = new RAMDirectory();  //内存字典
    IndexWriter writer = getWriter(); //io操作，需要输出流，理所当然
    for (int i = 0; i < ids.length; i++) 
{
      Document doc = new Document();
      doc.add(new Field("id", ids[i],      
                        Field.Store.YES, 
                        Field.Index.NOT_ANALYZED)); //id 没有必要分词
      doc.add(new Field("country", unindexed[i],
                        Field.Store.YES,
                        Field.Index.NO));
      doc.add(new Field("contents", unstored[i],
                        Field.Store.NO,
                        Field.Index.ANALYZED));//内容分词
      doc.add(new Field("city", text[i],  /**获取数据**/
                        Field.Store.YES,
                        Field.Index.ANALYZED)); /**分析数据**/

	writer.addDocument(doc);   /**加入文档**/

} 

writer.close();  /**生成index**/

}