删除可以是删除整个索引库，也可以根据文档id删除索引库下的文档，还可以通过query查询条件删除所有符合条件的数据。

一、删除整个索引库

下面的例子会删除indexName索引：

DeleteIndexResponse dResponse = client.admin().indices().prepareDelete(indexName)
                        .execute().actionGet();

可以根据DeleteIndexResponse对象的isAcknowledged()方法判断删除是否成功,返回值为boolean类型. 
如果传人的indexName不存在会出现异常.可以先判断索引是否存在：

IndicesExistsRequest inExistsRequest = new IndicesExistsRequest(indexName);

IndicesExistsResponse inExistsResponse = client.admin().indices()
                    .exists(inExistsRequest).actionGet();

根据IndicesExistsResponse对象的isExists()方法的boolean返回值可以判断索引库是否存在.

二、通过ID删除

下面的例子是删除索引名为blog，类型为article，id为1的文档：

DeleteResponse dResponse = client.prepareDelete("blog", "article", "1").execute().actionGet();

通过DeleteResponse对象的isFound()方法，可以得到删除是否成功，返回值为boolean类型.

三、通过Query删除

elasticsearch-2.3 中和旧版本api不太一样，安装插件：

sudo bin/plugin install delete-by-query

集群有多个节点的情况下，每个节点都需要安装并重启. 
如果想要移除插件，可以执行以下命令：

sudo bin/plugin remove delete-by-query

删除索引名为twitter，类型为tweet，user字段中含有kimchy的所有文档：

DELETE /twitter/tweet/_query?q=user:kimchy

Java api参考Elasticsearch Java Api(六)–DeleteByQuery。

四、java demo

package cn.com.bropen.es;

import static org.elasticsearch.index.query.QueryBuilders.termQuery; import java.net.InetAddress; import java.net.UnknownHostException; import org.elasticsearch.action.admin.indices.create.CreateIndexRequest; import org.elasticsearch.action.admin.indices.create.CreateIndexResponse; import org.elasticsearch.action.admin.indices.delete.DeleteIndexResponse; import org.elasticsearch.action.admin.indices.exists.indices.IndicesExistsRequest; import org.elasticsearch.action.admin.indices.exists.indices.IndicesExistsResponse; import org.elasticsearch.action.delete.DeleteResponse; import org.elasticsearch.client.Client; import org.elasticsearch.client.transport.TransportClient; import org.elasticsearch.common.transport.InetSocketTransportAddress; import org.elasticsearch.index.query.QueryBuilder; public class ElasticSearchCreate { private static String ServerIP = "127.0.0.1";// ElasticSearch server ip private static int ServerPort = 9300;// port private Client client; public static void main(String[] args) { try { Client client = TransportClient.builder().build().addTransportAddress( new InetSocketTransportAddress(InetAddress.getByName("127.0.0.1"), 9300)); DeleteResponse dResponse = client.prepareDelete("blog", "article", "11").execute() .actionGet(); if (dResponse.isFound()) { System.out.println("删除成功"); } else { System.out.println("删除失败"); } QueryBuilder qb1 = termQuery("title", "hibernate"); } catch (UnknownHostException e) { e.printStackTrace(); } deleteIndex("test");//删除名为test的索引库 } // 删除索引库 public static void deleteIndex(String indexName) { try { if (!isIndexExists(indexName)) { System.out.println(indexName + " not exists"); } else { Client client = TransportClient.builder().build().addTransportAddress( new InetSocketTransportAddress(InetAddress.getByName(ServerIP), ServerPort)); DeleteIndexResponse dResponse = client.admin().indices().prepareDelete(indexName) .execute().actionGet(); if (dResponse.isAcknowledged()) { System.out.println("delete index "+indexName+" successfully!"); }else{ System.out.println("Fail to delete index "+indexName); } } } catch (UnknownHostException e) { e.printStackTrace(); } } // 创建索引库 public static void createIndex(String indexName) { try { Client client = TransportClient.builder().build().addTransportAddress( new InetSocketTransportAddress(InetAddress.getByName(ServerIP), ServerPort)); // 创建索引库 if (isIndexExists("indexName")) { System.out.println("Index " + indexName + " already exits!"); } else { CreateIndexRequest cIndexRequest = new CreateIndexRequest("indexName"); CreateIndexResponse cIndexResponse = client.admin().indices().create(cIndexRequest) .actionGet(); if (cIndexResponse.isAcknowledged()) { System.out.println("create index successfully！"); } else { System.out.println("Fail to create index!"); } } } catch (UnknownHostException e) { e.printStackTrace(); } } // 判断索引是否存在 传入参数为索引库名称 public static boolean isIndexExists(String indexName) { boolean flag = false; try { Client client = TransportClient.builder().build().addTransportAddress( new InetSocketTransportAddress(InetAddress.getByName(ServerIP), ServerPort)); IndicesExistsRequest inExistsRequest = new IndicesExistsRequest(indexName); IndicesExistsResponse inExistsResponse = client.admin().indices() .exists(inExistsRequest).actionGet(); if (inExistsResponse.isExists()) { flag = true; } else { flag = false; } } catch (UnknownHostException e) { e.printStackTrace(); } return flag; } }