16、ElasticSearch 7.3 实战：RestHighLevelClient Java api实现索引的创建、删除、是否存在、关闭、开启
1、写在前面
注意：导入的包区别，不同的包创建索引的方式不同。博主亲身实践，具体体现在createIndexRequest.mapping()里面。读者可自行试验。
import org.elasticsearch.client.indices.CreateIndexRequest;
import org.elasticsearch.action.admin.indices.create.CreateIndexRequest;
由此可以猜想一下：
import org.elasticsearch.client.indices.*;
import org.elasticsearch.action.admin.indices.*;
可以看到上述两种方式导入的包的子类名是相同的，但是具体对索引的操作方式可能是不同的。具体的区别博主暂时还不清楚，后续若有进展再在此处更新。
2、同步创建索引
例如要实现如下索引的创建
PUT /my_index
{
"settings": {
"number_of_shards": 1,
"number_of_replicas": 1
},
"mappings": {
"properties": {
"name": {
"type": "keyword"
},
"description": {
"type": "text"
},
"price": {
"type": "long"
},
"pic": {
"type": "text",
"index": false
}
}
},
"aliases": {
"default_index": {}
}
}
代码如下（3种方式）：
//创建索引
@Test
public void testCreateIndex() throws IOException {
//创建索引对象
CreateIndexRequest createIndexRequest = new CreateIndexRequest("itheima_book");
//设置参数
createIndexRequest.settings(Settings.builder().put("number_of_shards", "1").put("number_of_replicas", "0"));
//指定映射1
createIndexRequest.mapping(" {\n" +
" \t\"properties\": {\n" +
" \"name\":{\n" +
" \"type\":\"keyword\"\n" +
" },\n" +
" \"description\": {\n" +
" \"type\": \"text\"\n" +
" },\n" +
" \"price\":{\n" +
" \"type\":\"long\"\n" +
" },\n" +
" \"pic\":{\n" +
" \"type\":\"text\",\n" +
" \"index\":false\n" +
" }\n" +
" \t}\n" +
"}", XContentType.JSON);
//指定映射2
// Map<String, Object> message = new HashMap<>();
// message.put("type", "text");
// Map<String, Object> properties = new HashMap<>();
// properties.put("message", message);
// Map<String, Object> mapping = new HashMap<>();
// mapping.put("properties", properties);
// createIndexRequest.mapping(mapping);
//指定映射3
// XContentBuilder builder = XContentFactory.jsonBuilder();
// builder.startObject();
// {
// builder.startObject("properties");
// {
// builder.startObject("message");
// {
// builder.field("type", "text");
// }
// builder.endObject();
// }
// builder.endObject();
// }
// builder.endObject();
// createIndexRequest.mapping(builder);
//设置别名
createIndexRequest.alias(new Alias("itheima_index_new"));
// 额外参数
//设置超时时间
createIndexRequest.setTimeout(TimeValue.timeValueMinutes(2));
//设置主节点超时时间
createIndexRequest.setMasterTimeout(TimeValue.timeValueMinutes**1、** );
//在创建索引API返回响应之前等待的活动分片副本的数量，以int形式表示
createIndexRequest.waitForActiveShards(ActiveShardCount.from(2));
createIndexRequest.waitForActiveShards(ActiveShardCount.DEFAULT);
//操作索引的客户端
IndicesClient indices = client.indices();
//执行创建索引库
CreateIndexResponse createIndexResponse = indices.create(createIndexRequest, RequestOptions.DEFAULT);
//得到响应（全部）
boolean acknowledged = createIndexResponse.isAcknowledged();
//得到响应 指示是否在超时前为索引中的每个分片启动了所需数量的碎片副本
boolean shardsAcknowledged = createIndexResponse.isShardsAcknowledged();
System.out.println("acknowledged:" + acknowledged);
System.out.println("shardsAcknowledged:" + shardsAcknowledged);
}
3、异步创建索引
//创建索引异步方式
@Test
public void testCreateIndexAsync() throws IOException {
//创建索引对象
CreateIndexRequest createIndexRequest = new CreateIndexRequest("itheima_book");
//设置参数
createIndexRequest.settings(Settings.builder().put("number_of_shards", "1").put("number_of_replicas", "0"));
//指定映射1 与创建文档做类别
createIndexRequest.mapping(" {\n" +
" \t\"properties\": {\n" +
" \"name\":{\n" +
" \"type\":\"keyword\"\n" +
" },\n" +
" \"description\": {\n" +
" \"type\": \"text\"\n" +
" },\n" +
" \"price\":{\n" +
" \"type\":\"long\"\n" +
" },\n" +
" \"pic\":{\n" +
" \"type\":\"text\",\n" +
" \"index\":false\n" +
" }\n" +
" \t}\n" +
"}", XContentType.JSON);
//指定映射2
// Map<String, Object> message = new HashMap<>();
// message.put("type", "text");
// Map<String, Object> properties = new HashMap<>();
// properties.put("message", message);
// Map<String, Object> mapping = new HashMap<>();
// mapping.put("properties", properties);
// createIndexRequest.mapping(mapping);
//指定映射3
// XContentBuilder builder = XContentFactory.jsonBuilder();
// builder.startObject();
// {
// builder.startObject("properties");
// {
// builder.startObject("message");
// {
// builder.field("type", "text");
// }
// builder.endObject();
// }
// builder.endObject();
// }
// builder.endObject();
// createIndexRequest.mapping(builder);
//设置别名
createIndexRequest.alias(new Alias("itheima_index_new"));
// 额外参数
//设置超时时间
createIndexRequest.setTimeout(TimeValue.timeValueMinutes(2));
//设置主节点超时时间
createIndexRequest.setMasterTimeout(TimeValue.timeValueMinutes**1、** );
//在创建索引API返回响应之前等待的活动分片副本的数量，以int形式表示
createIndexRequest.waitForActiveShards(ActiveShardCount.from(2));
createIndexRequest.waitForActiveShards(ActiveShardCount.DEFAULT);
//操作索引的客户端
IndicesClient indices = client.indices();
//执行创建索引库
// CreateIndexResponse createIndexResponse = indices.create(createIndexRequest, RequestOptions.DEFAULT);
ActionListener<CreateIndexResponse> listener = new ActionListener<CreateIndexResponse>() {
@Override
public void onResponse(CreateIndexResponse createIndexResponse) {
//得到响应（全部）
boolean acknowledged = createIndexResponse.isAcknowledged();
//得到响应 指示是否在超时前为索引中的每个分片启动了所需数量的碎片副本
boolean shardsAcknowledged = createIndexResponse.isShardsAcknowledged();
System.out.println("acknowledged:" + acknowledged);
System.out.println("shardsAcknowledged:" + shardsAcknowledged);
}
@Override
public void onFailure(Exception e) {
e.printStackTrace();
}
};
client.indices().createAsync(createIndexRequest, RequestOptions.DEFAULT, listener);
try {
Thread.sleep(5000);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
4、同步删除索引
// 删除索引
@Test
public void testDeleteIndex() throws IOException {
//创建删除索引请求
DeleteIndexRequest deleteIndexRequest = new DeleteIndexRequest("itheima_book");
// 执行
AcknowledgedResponse delete = client.indices().delete(deleteIndexRequest, RequestOptions.DEFAULT);
//得到相应
boolean acknowledged = delete.isAcknowledged();
System.out.println("acknowledged:" + acknowledged);
}
5、异步删除索引
// 删除索引异步操作
@Test
public void testDeleteIndexAsync() throws IOException {
//创建删除索引请求
DeleteIndexRequest deleteIndexRequest = new DeleteIndexRequest("itheima_book");
// 执行
ActionListener<AcknowledgedResponse> listener = new ActionListener<AcknowledgedResponse>() {
@Override
public void onResponse(AcknowledgedResponse acknowledgedResponse) {
//得到相应
boolean acknowledged = acknowledgedResponse.isAcknowledged();
System.out.println("acknowledged:" + acknowledged);
}
@Override
public void onFailure(Exception e) {
e.printStackTrace();
}
};
// AcknowledgedResponse delete = client.indices().delete(deleteIndexRequest, RequestOptions.DEFAULT);
}
6、索引是否存在
//index exist api
@Test
public void testExistIndex() throws IOException {
GetIndexRequest request=new GetIndexRequest("itheima_book");
//参数
request.local(false);//从主节点返回本地索引信息状态
request.humanReadable(true);//以适合人类的格式返回
request.includeDefaults(false);//是否返回每个索引的所有默认配置
boolean exists = client.indices().exists(request, RequestOptions.DEFAULT);
System.out.println("exists:"+exists);
}
7、关闭索引
//关闭索引
@Test
public void testCloseIndex() throws IOException {
CloseIndexRequest request=new CloseIndexRequest("itheima_book");
AcknowledgedResponse close = client.indices().close(request, RequestOptions.DEFAULT);
boolean acknowledged = close.isAcknowledged();
System.out.println("acknowledged:"+acknowledged);
}
8、开启索引
//开启索引
@Test
public void testOpenIndex() throws IOException {
OpenIndexRequest request=new OpenIndexRequest("itheima_book");
OpenIndexResponse open = client.indices().open(request, RequestOptions.DEFAULT);
boolean acknowledged = open.isAcknowledged();
System.out.println("acknowledged:"+acknowledged);
}