package com.wp.util;

import java.nio.file.Paths;

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.StringField;

import org.apache.lucene.document.TextField;

import org.apache.lucene.index.DirectoryReader;

import org.apache.lucene.index.IndexReader;

import org.apache.lucene.index.IndexWriter;

import org.apache.lucene.index.IndexWriterConfig;

import org.apache.lucene.index.Term;

import org.apache.lucene.store.Directory;

import org.apache.lucene.store.FSDirectory;

import org.junit.Before;

import org.junit.Test;

public class IndexIngTest {

    private String ids[] = { "1", "2", "3" };

    private String citys[] = { "qingdao", "nanjing", "shanghai" };

    private String descs[] = { "Qingdao is a beautiful city.",

            "Nanjing is a city of culture.", "Shanghai is a bustling city." };

    private Directory dir;// 目录

    /**

     * 获取IndexWriter实例

     *

     * @return

     * @throws Exception

     */

    private IndexWriter getWriter() throws Exception {

        Analyzer analyzer = new StandardAnalyzer(); // 标准分词器

        IndexWriterConfig iwc = new IndexWriterConfig(analyzer);

        IndexWriter writer = new IndexWriter(dir, iwc);

        return writer;

    }

    /**

     * 添加文档

     *

     * @throws Exception

     */

    @Before

    public void setUp() throws Exception {

        dir = FSDirectory.open(Paths.get("D:\\lucene\\luceneIndex"));// 得到luceneIndex目录

        IndexWriter writer = getWriter();// 得到索引

        for (int i = 0; i < ids.length; i++) {

            Document doc = new Document();// 创建文档

            doc.add(new StringField("id", ids[i], Field.Store.YES));// 将id属性存入内存中

            doc.add(new StringField("city", citys[i], Field.Store.YES));

            doc.add(new TextField("desc", descs[i], Field.Store.NO));

            writer.addDocument(doc); // 添加文档

        }

        writer.close();

    }

    /**

     * 测试写了几个文档

     *

     * @throws Exception

     */

    @Test

    public void testIndexWriter() throws Exception {

        IndexWriter writer = getWriter();

        System.out.println("写入了" + writer.numDocs() + "个文档");

        writer.close();

    }

    /**

     * 测试读取文档

     *

     * @throws Exception

     */

    @Test

    public void testIndexReader() throws Exception {

        IndexReader reader = DirectoryReader.open(dir);

        System.out.println("最大文档数：" + reader.maxDoc());

        System.out.println("实际文档数：" + reader.numDocs());

        reader.close();

    }

    /**

     * 测试删除 在合并前（先删除后增加，结果为删除前的结果）

     *

     * @throws Exception

     */

    @Test

    public void testDeleteBeforeMerge() throws Exception {

        IndexWriter writer = getWriter();

        System.out.println("删除前：" + writer.numDocs());

        writer.deleteDocuments(new Term("id", "1"));// term：根据id找到为1的

        writer.commit();

        System.out.println("writer.maxDoc()：" + writer.maxDoc());

        System.out.println("writer.numDocs()：" + writer.numDocs());

        writer.close();

    }

    /**

     * 测试删除 在合并后（先删除后增加，结果为删除后的结果）

     *

     * @throws Exception

     */

    @Test

    public void testDeleteAfterMerge() throws Exception {

        IndexWriter writer = getWriter();

        System.out.println("删除前：" + writer.numDocs());

        writer.deleteDocuments(new Term("id", "1"));

        writer.forceMergeDeletes(); // 强制删除

        writer.commit();

        System.out.println("writer.maxDoc()：" + writer.maxDoc());

        System.out.println("writer.numDocs()：" + writer.numDocs());

        writer.close();

    }

    /**

     * 测试更新

     *

     * @throws Exception

     */

    @Test

    public void testUpdate() throws Exception {

        IndexWriter writer = getWriter();

        Document doc = new Document();

        doc.add(new StringField("id", "1", Field.Store.YES));

        doc.add(new StringField("city", "qingdao", Field.Store.YES));

        doc.add(new TextField("desc", "dsss is a city.", Field.Store.NO));

        writer.updateDocument(new Term("id", "1"), doc);

        writer.close();

    }

}