Java日記-強力なElastisearch検索エンジンを使用

Elastisearchは強力で、使いやすい検索エンジンでシステム上でElastisearchを実行するには以下のステップしかかかりません.
1.Elastisearchをダウンロード

wget https://artifacts.elastic.co/downloads/elasticsearch/elasticsearch-5.4.0.zip

2.解凍

unzip elasticsearch-5.4.0.zip

3.運転

elasticsearch-5.4.0/bin/elasticsearch

メモリオーバーフロー(OOM)、elastisearchが消費するメモリが非常に大きいため、メモリの小さいサーバで実行するにはjvmのメモリサイズを変更する必要があります.

vi elasticsearch-5.4.0/config/jvm.options

22行と23行のスタックサイズを512 Mに変更

-Xms512M
-Xmx512M

再起動してもkilledならもう少し小さくしてください
4.テストが成功したか

curl    'http://localhost:9200/?pretty'

次のメッセージが表示されます.

{
            "status":   200,
            "name": "Shrunken   Bones",
            "version":  {
                        "number":   "1.4.0",
                        "lucene_version":   "4.10"
            },
            "tagline":  "You    Know,   for Search"
}

起動に成功したことを示します
次にJavaのAPIでElasticsearchを操作します
まずelastisearchとlog 4 jをインポートしたパッケージ
POM

    4.0.0

    com.jk
    ElasticsearchExample
    1.0-SNAPSHOT
    
        
            org.elasticsearch.client
            transport
            
            5.4.0
        
        
            org.apache.logging.log4j
            log4j-api
            2.7
        
    

以下はよく使われるいくつかの操作です.
1.クライアントの作成

Client client = null;
        try {
            client = new PreBuiltTransportClient(Settings.EMPTY)
                    .addTransportAddress(new InetSocketTransportAddress(InetAddress.getByName("localhost"), 9300));
        } catch (Exception e) {
            e.printStackTrace();
        }

2.索引の作成

/**
     *     ，     
     * @param client
     */
    private static void recreateIndex(Client client) {
        if (client.admin().indices().prepareExists(index).execute().actionGet()
                .isExists()) {
            DeleteIndexResponse deleteIndexResponse = client.admin().indices()
                    .delete(new DeleteIndexRequest(index)).actionGet();
            System.out.println("delete index :");
            System.out.println(deleteIndexResponse);
        }

        CreateIndexResponse createIndexResponse = client.admin().indices()
                .prepareCreate(index).execute().actionGet();
        System.out.println("create index :");
        System.out.println(createIndexResponse);
    }

3.データの挿入

/**
     *     
     * @param client
     */
    @SuppressWarnings({"rawtypes", "unchecked"})
    private static void doIndex(final Client client) {
        Map s11 = new LinkedHashMap();
        s11.put("title", "Think in java");
        s11.put("origin", "  ");
        s11.put("description", "  java        ");
        s11.put("author", "Bruce Eckel");
        s11.put("price", 108);

        Map s12 = new LinkedHashMap();
        s12.put("title", "Head First Java");
        s12.put("origin", "  ");
        s12.put("description", "java    ");
        s12.put("author", "Kathy Sierra");
        s12.put("price", 54);

        Map s21 = new LinkedHashMap();
        s21.put("title", "Design Pattern");
        s21.put("origin", "  ");
        s21.put("description", "            ");
        s21.put("author", "Kathy Sierra");
        s21.put("price", 89);

        Map s22 = new LinkedHashMap();
        s22.put("title", "     ");
        s22.put("origin", "  ");
        s22.put("description", "        ");
        s22.put("author", "Paul Graham");
        s22.put("price", 35);

        BulkResponse bulkResponse = client
                .prepareBulk()
                .add(client.prepareIndex(index, type).setId("11").setSource(s11).setOpType(IndexRequest.OpType.INDEX).request())
                .add(client.prepareIndex(index, type).setId("12").setSource(s12).setOpType(IndexRequest.OpType.INDEX).request())
                .add(client.prepareIndex(index, type).setId("21").setSource(s21).setOpType(IndexRequest.OpType.INDEX).request())
                .add(client.prepareIndex(index, type).setId("22").setSource(s22).setOpType(IndexRequest.OpType.INDEX).request())
                .execute().actionGet();
        if (bulkResponse.hasFailures()) {
            System.err.println("index docs ERROR:" + bulkResponse.buildFailureMessage());
        } else {
            System.out.println("index docs SUCCESS:");
            System.out.println(bulkResponse);
        }
    }

4.すべてのクエリー

    /**
     *     
     */
    private static void searchAll(Client client) {
        SearchResponse response = client.prepareSearch(index)
                .setQuery(QueryBuilders.matchAllQuery())
                .setExplain(true).execute().actionGet();
        System.out.println("searchAll : ");
        for (SearchHit searchHit : response.getHits()) {
            System.out.println("********");
            System.out.println(searchHit.getSource());
        }
    }

5.キーワード検索

    /**
     *      
     *
     * @param client
     */
    private static void searchKeyWord(Client client) {
        SearchResponse response = client.prepareSearch(index)
                //           
                .setQuery(QueryBuilders.matchQuery("_all", "  "))
                //        
//                .setQuery(QueryBuilders.matchQuery("_all", "  ").minimumShouldMatch("100%"))
                .execute().actionGet();
        System.out.println("searchKeyWord : ");
        System.out.println(response);
    }

6.数値範囲フィルタ

    /**
     *       
     *
     * @param client
     */
    private static void searchRange(Client client) {
        SearchResponse response = client.prepareSearch(index).
                //  80，  100
                setQuery(QueryBuilders.rangeQuery("price").gt(80).lt(100))
                .execute()
                .actionGet();
        System.out.println("searchRange : ");
        System.out.println(response);
    }

7.ソート

    /**
     *   
     *
     * @param client
     */
    private static void searchOrdered(Client client) {
        SearchResponse response = client.prepareSearch(index)
                .setQuery(QueryBuilders.matchAllQuery())
                //        
                .addSort(SortBuilders.fieldSort("price")
                        .order(SortOrder.DESC)).execute().actionGet();
        System.out.println("searchOrdered : ");
        System.out.println(response);
    }

8.ハイライトキー

/**
     *      
     * @param client
     */
    private static void searchHightlight(Client client) {
        //      
        HighlightBuilder highlightBuilder = new HighlightBuilder();
        highlightBuilder.field("title");
        highlightBuilder.field("description");
        SearchResponse response = client.prepareSearch(index)
                //     ，          
//                .setQuery(QueryBuilders.matchQuery("title", "java"))
                //     ，           
                .setQuery(QueryBuilders.multiMatchQuery("      ", "title", "description"))
                .highlighter(highlightBuilder)
                .execute()
                .actionGet();
        System.out.println("searchHightlight : ");
        System.out.println(response);
    }

9.idによる検索

    /**
     *   id  
     * @param client
     */
    private static void findById(final Client client) {
        String id="12";
        GetResponse response = client.prepareGet(index, type, id).get();
        System.out.println("findById");
        System.out.println(response);
    }

10.削除

     /**
     *   
     * @param client
     */
    private static void deleteById(Client client) {
        String id="12";
        DeleteResponse response = client.prepareDelete(index, type, id).get();
    }

11.更新

    /**
     *   
     * @param client
     */
    private static void updateById(Client client) {
        try {
            String id="11";
            client.prepareUpdate(index, type, id)
                    .setDoc(jsonBuilder()
                            .startObject()
                            .field("title", "   ")
                            .endObject())
                    .get();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

よく使う操作はこれだけで、コードはhttps://github.com/jkgeekJack/ElasticsearchExample
Elasticsearch:権威ガイドもご覧になることをお勧めします.ここではもっと詳しく紹介します.