elasticsearch-2.3.5示列代码

2018-09-05

一、简介

该示列是基于elasticsearch-2.3.5版本开发，参考地址：https://www.elastic.co/guide/en/elasticsearch/client/java-api/2.3/index.html

二、Maven依赖

<dependency>
    <groupId>org.elasticsearch</groupId>
    <artifactId>elasticsearch</artifactId>
    <version>2.3.5</version>
</dependency>
<dependency>
    <groupId>com.alibaba</groupId>
    <artifactId>fastjson</artifactId>
    <version>1.1.35</version>
</dependency>

三、Java代码

package easticsearch;

import com.alibaba.fastjson.JSON;
import org.elasticsearch.action.delete.DeleteResponse;
import org.elasticsearch.action.get.GetResponse;
import org.elasticsearch.action.index.IndexResponse;
import org.elasticsearch.action.search.SearchResponse;
import org.elasticsearch.action.update.UpdateRequest;
import org.elasticsearch.client.transport.TransportClient;
import org.elasticsearch.common.settings.Settings;
import org.elasticsearch.common.transport.InetSocketTransportAddress;
import org.elasticsearch.index.query.QueryBuilder;
import org.elasticsearch.index.query.QueryBuilders;
import org.elasticsearch.search.SearchHit;
import org.elasticsearch.search.SearchHits;

import java.net.InetAddress;
import java.util.ArrayList;
import java.util.Date;
import java.util.List;
import java.util.Map;

/**
 * Created by zhengyong on 16/11/22.
 */
public class Elasticsearch {

    private static TransportClient client   = null;

    /**
     * es index
     */
    private static final String    ES_INDEX = "database_test";
    /**
     * es type
     */
    private static final String    ES_TYPE  = "user";

    public static void main(String[] args) throws Exception {

        createClient();

        String _id = createIndex();

        getDataResponse(_id);

        updateData(_id);

        getDataResponse(_id);

        QueryBuilder builder = QueryBuilders.matchAllQuery();
        // QueryBuilder builder = QueryBuilders.termQuery("username", "zhengyong");
        queryDataList(builder);

        // deleteDataResponse(_id);

        shutdown();
    }

    private static void createClient() throws Exception {
        if (client == null) {
            synchronized (Elasticsearch.class) {
                Settings settings = Settings.settingsBuilder().put("cluster.name", "myCluster").build();
                client = TransportClient.builder().settings(settings).build().addTransportAddress(new InetSocketTransportAddress(InetAddress.getByName("localhost"),
                                                                                                                                 9300));
            }
        }
    }

    /**
     * 创建es库并导入数据
     * 
     * @return _id
     */
    private static String createIndex() {
        String json = "{" + "\"username\":\"zhengyong\"," + "\"postDate\":\"" + new Date().toLocaleString() + "\","
                      + "\"message\":\"create\"" + "}";

        IndexResponse response = client.prepareIndex(ES_INDEX, ES_TYPE).setSource(json).get();

        System.out.println(String.format("create index response: %s", response.toString()));

        return response.getId();
    }

    /**
     * 根据_id获取数据
     * 
     * @param _id 唯一标识
     * @return GetResponse
     */
    private static GetResponse getDataResponse(String _id) {
        GetResponse response = client.prepareGet(ES_INDEX, ES_TYPE, _id).get();
        System.out.println(String.format("get data response: %s", JSON.toJSONString(response.getSource())));
        return response;
    }

    /**
     * 根据查询条件查询结果集
     * 
     * @param queryBuilder 查询条件
     * @return List
     */
    private static List<String> queryDataList(QueryBuilder queryBuilder) {
        SearchResponse sResponse = client.prepareSearch(ES_INDEX).setTypes(ES_TYPE).setQuery(queryBuilder).setSize(1000).execute().actionGet();
        SearchHits hits = sResponse.getHits();

        List<String> list = new ArrayList<>();
        System.out.println(hits.getTotalHits());
        SearchHit[] hitArray = hits.hits();
        for (SearchHit hit : hitArray) {
            Map<String, Object> map = hit.getSource();

            String username = (String) map.get("username");
            String postDate = (String) map.get("postDate");
            String message = (String) map.get("message");

            StringBuilder br = new StringBuilder();
            br.append(username).append("_").append(message).append("_").append(postDate);
            list.add(br.toString());
        }

        System.out.println(String.format("query data count=%s, list : %s", list.size(), JSON.toJSONString(list)));

        return list;
    }

    /**
     * 根据_id删除数据
     * 
     * @param _id 唯一标识
     * @return DeleteResponse
     */
    private static DeleteResponse deleteDataResponse(String _id) {
        DeleteResponse response = client.prepareDelete(ES_INDEX, ES_TYPE, _id).get();
        System.out.println(String.format("delete data response: %s", JSON.toJSONString(response)));
        return response;
    }

    /**
     * 根据_id跟下数据
     * 
     * @param _id 唯一标识
     * @throws Exception
     */
    private static void updateData(String _id) throws Exception {
        UpdateRequest updateRequest = new UpdateRequest();
        updateRequest.index(ES_INDEX);
        updateRequest.type(ES_TYPE);
        updateRequest.id(_id);

        String json = "{" + "\"username\":\"lisi\"," + "\"postDate\":\"" + new Date().toLocaleString() + "\","
                      + "\"message\":\"update\"" + "}";

        updateRequest.doc(json);

        client.update(updateRequest).get();
    }

    private static void shutdown() {
        if (client == null) {
            client.close();
        }
    }

}

四、异常信息

开发时由于maven依赖elasticsearch版本与安装包版本不一致，出现以下异常：

Exception in thread "main" NoNodeAvailableException[None of the configured nodes are available: []]
	at org.elasticsearch.client.transport.TransportClientNodesService.ensureNodesAreAvailable(TransportClientNodesService.java:314)
	at org.elasticsearch.client.transport.TransportClientNodesService.execute(TransportClientNodesService.java:228)
	at org.elasticsearch.client.transport.support.TransportProxyClient.execute(TransportProxyClient.java:63)
	at org.elasticsearch.client.transport.TransportClient.doExecute(TransportClient.java:326)
	at org.elasticsearch.client.support.AbstractClient.execute(AbstractClient.java:403)
	at org.elasticsearch.action.ActionRequestBuilder.execute(ActionRequestBuilder.java:80)
	at org.elasticsearch.action.ActionRequestBuilder.execute(ActionRequestBuilder.java:54)
	at org.elasticsearch.action.ActionRequestBuilder.get(ActionRequestBuilder.java:62)
	at easticsearch.Elasticsearch.createIndex(Elasticsearch.java:51)
	at easticsearch.Elasticsearch.main(Elasticsearch.java:23)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.lang.reflect.Method.invoke(Method.java:497)
	at com.intellij.rt.execution.application.AppMain.main(AppMain.java:144)

五、解决办法

1	需要elasticsearch-2.3.5与client的jar版本一致