1. 今天写了一段ES的测试代码，如下：

   package elasticSearch;

   import java.net.InetSocketAddress; import java.util.ArrayList; import java.util.List; import java.util.Map;

   import org.elasticsearch.action.index.IndexRequestBuilder; import org.elasticsearch.action.index.IndexResponse; import org.elasticsearch.action.search.SearchResponse; import org.elasticsearch.client.Client; 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 entity.Person; import util.JsonUtils;

   public class ESTest {

   private Client client;
   
   public ESTest() {
       this("localhost");
   }
   
   public ESTest(String ip) {
       Settings settings = Settings.settingsBuilder().put("cluster.name", "huiTest")
               .build();
       client = TransportClient.builder().settings(settings).build();
       client = ((TransportClient) client).addTransportAddress(
               new InetSocketTransportAddress(new InetSocketAddress(ip, 9300)));
   
   }
   
   public IndexResponse createIndex(String indexName, String type,
           List<String> jsonArray) {
   
       IndexRequestBuilder builder = client.prepareIndex(indexName, type);
       for (String jsonTemp : jsonArray) {
           System.out.println(jsonTemp);
           builder = builder.setSource(jsonTemp);
       }
       IndexResponse response = builder.execute().actionGet();
       return response;
   
   }
   
   public List<Person> search(QueryBuilder queryBuilder, String indexName, String type) {
       List<Person> persons = new ArrayList<>();
   
       SearchResponse sResponse = client.prepareSearch(indexName).setTypes(type)
               .setQuery(queryBuilder).execute().actionGet();
       SearchHits hits = sResponse.getHits();
   
       System.out.println(hits.getTotalHits());
       Double salary = 0.0;
       SearchHit[] hitArray = hits.hits();
       for (SearchHit hit : hitArray) {
           Map<String, Object> map = hit.getSource();
   
           Integer age = (Integer) map.get("age");
           String name = (String) map.get("name");
           Object salaryO = map.get("salary");
           if (salaryO instanceof Integer) {
               salary = (Integer) salaryO * 1.0;
           } else {
               salary = (Double) salaryO;
           }
           Person p = new Person(name, age, salary);
   
           persons.add(p);
       }
       return persons;
   }
   
   public static void main(String[] args) {
       ESTest esTest = new ESTest();
   
       List<Person> persons = JsonUtils.getData(10);
       List<String> jsonArray = JsonUtils.covertList2String(persons);
   
       String indexName = "liuhui'sindex";// 要小写
       String type = "liuhui'sType";
        esTest.createIndex(indexName, type, jsonArray);
   
       // QueryBuilder builder = QueryBuilders.matchAllQuery();
       // QueryBuilder builder = QueryBuilders.termQuery("name", "hui10");
       QueryBuilder builder = QueryBuilders.termQuery("age", "20");
   
       List<Person> list = esTest.search(builder, indexName, type);
       System.out.println(list);
   
   }
   

   }

运行时报错如下：

Exception in thread "main" NoNodeAvailableException[None of the configured nodes are available: [{#transport#-1}{127.0.0.1}{localhost/127.0.0.1:9300}]]
     at org.elasticsearch.client.transport.TransportClientNodesService.ensureNodesAreAvailable(TransportClientNodesService.java:290)
     at org.elasticsearch.client.transport.TransportClientNodesService.execute(TransportClientNodesService.java:207)
     at org.elasticsearch.client.transport.support.TransportProxyClient.execute(TransportProxyClient.java:55)
     at org.elasticsearch.client.transport.TransportClient.doExecute(TransportClient.java:288)
     at org.elasticsearch.client.support.AbstractClient.execute(AbstractClient.java:359)
     at org.elasticsearch.action.ActionRequestBuilder.execute(ActionRequestBuilder.java:86)
     at org.elasticsearch.action.ActionRequestBuilder.execute(ActionRequestBuilder.java:56)
     at elasticSearch.ESTest.search( ESTest.java:60)
     at elasticSearch.ESTest.main( ESTest.java:99)

造成这一异常的原因，仅我所知的，有以下几个：

1. 运行该客户端时 elasticsearch.bat未启动；

2. cluster.name:huiTest未在ES的安装目录config下的elasticsearch.yml中配置，即如果代码里使用了put("cluster.name","huiTest")，则一定要在elasticsearch.yml中添加一行配置：cluster.name:huiTest，因为cluster.name默认是elasticsearch。当然也可以不使用put("cluster.name","huiTest")，或者使用put("cluster.name","elasticsearch");这里要注意如果修改了elasticsearch.yml文件，一定要重启elasticsearch.bat；

3. 客户端端口不是用的9300，而是9200.9200是为http协议准备的，9300才是客户端使用的；

   以上3条逐个排查，多半问题就解决了；