Elasticsearch-RestClient基础
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- 一、认识RestClient
-
- 二、使用RestClient
1、基础准备- 2、RestClient操作索引库 ... ③ 编写创建索引库方法 ④ 编写删除索引库方法 ⑤ 编写判断是否存在索引库方法 3、RestClient操作文档 ① 添加文档数据方法 ② 获取文档数据方法 ③ 更新文档数据方法 ④ 删除文档数方法 ⑤ 批量操作方法
一、认识RestClient
Java REST Client (deprecated) | ElasticOverview (rest-high-level 7.12.1 API) (elastic.co)
ES官方提供了各种不同语言的客户端，用来操作ES。这些客户端的本质就是组装DSL语句，通过http请求发送给ES。
RestClient是提供给Java的客户端。
二、使用RestClient
1、基础准备
- ① 创建表格
创建数据表tb_hotel，如下：
DROP TABLE IF EXISTS `tb_hotel`;
CREATE TABLE `tb_hotel` (
`id` bigint(20) NOT NULL COMMENT 酒店id,
`name` varchar(255) CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci NOT NULL COMMENT 酒店名称,
`address` varchar(255) CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci NOT NULL COMMENT 酒店地址,
`price` int(10) NOT NULL COMMENT 酒店价格,
`score` int(2) NOT NULL COMMENT 酒店评分,
`brand` varchar(32) CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci NOT NULL COMMENT 酒店品牌,
`city` varchar(32) CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci NOT NULL COMMENT 所在城市,
`star_name` varchar(16) CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci NULL DEFAULT NULL COMMENT 酒店星级，1星到5星，1钻到5钻,
`business` varchar(255) CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci NULL DEFAULT NULL COMMENT 商圈,
`latitude` varchar(32) CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci NOT NULL COMMENT 纬度,
`longitude` varchar(32) CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci NOT NULL COMMENT 经度,
`pic` varchar(255) CHARACTER SET utf8mb4 COLLATE utf8mb4_general_ci NULL DEFAULT NULL COMMENT 酒店图片,
PRIMARY KEY (`id`) USING BTREE
) ENGINE = InnoDB CHARACTER SET = utf8mb4 COLLATE = utf8mb4_general_ci ROW_FORMAT = Compact;
插入数据，如下：
INSERT INTO `tb_hotel` VALUES (36934, 7天连锁酒店(上海宝山路地铁站店), 静安交通路40号, 336, 37, 7天酒店, 上海, 二钻, 四川北路商业区, 31.251433, 121.47522, https://m.tuniucdn.com/fb2/t1/G1/M00/3E/40/Cii9EVkyLrKIXo1vAAHgrxo_pUcAALcKQLD688AAeDH564_w200_h200_c1_t0.jpg);
INSERT INTO `tb_hotel` VALUES (38609, 速8酒店(上海赤峰路店), 广灵二路126号, 249, 35, 速8, 上海, 二钻, 四川北路商业区, 31.282444, 121.479385, https://m.tuniucdn.com/fb2/t1/G2/M00/DF/96/Cii-TFkx0ImIQZeiAAITil0LM7cAALCYwKXHQ4AAhOi377_w200_h200_c1_t0.jpg);
INSERT INTO `tb_hotel` VALUES (38665, 速8酒店上海中山北路兰田路店, 兰田路38号, 226, 35, 速8, 上海, 二钻, 长风公园地区, 31.244288, 121.422419, https://m.tuniucdn.com/fb2/t1/G2/M00/EF/86/Cii-Tlk2mV2IMZ-_AAEucgG3dx4AALaawEjiycAAS6K083_w200_h200_c1_t0.jpg);
INSERT INTO `tb_hotel` VALUES (38812, 7天连锁酒店(上海漕溪路地铁站店), 徐汇龙华西路315弄58号, 298, 37, 7天酒店, 上海, 二钻, 八万人体育场地区, 31.174377, 121.442875, https://m.tuniucdn.com/fb2/t1/G2/M00/E0/0E/Cii-TlkyIr2IEWNoAAHQYv7i5CkAALD-QP2iJwAAdB6245_w200_h200_c1_t0.jpg);
INSERT INTO `tb_hotel` VALUES (39106, 7天连锁酒店（上海莘庄地铁站店）, 闵行莘庄镇七莘路299号, 348, 41, 7天酒店, 上海, 二钻, 莘庄工业区, 31.113812, 121.375869, https://m.tuniucdn.com/fb2/t1/G2/M00/D8/11/Cii-T1ku2zGIGR7uAAF1NYY9clwAAKxZAHO8HgAAXVN368_w200_h200_c1_t0.jpg);
INSERT INTO `tb_hotel` VALUES (39141, 7天连锁酒店(上海五角场复旦同济大学店), 杨浦国权路315号, 349, 38, 7天酒店, 上海, 二钻, 江湾、五角场商业区, 31.290057, 121.508804, https://m.tuniucdn.com/fb2/t1/G2/M00/C7/E3/Cii-T1knFXCIJzNYAAFB8-uFNAEAAKYkQPcw1IAAUIL012_w200_h200_c1_t0.jpg);
INSERT INTO `tb_hotel` VALUES (416121, 如家酒店(北京西客站北广场店), 莲花池东路120-2号6层, 275, 43, 如家, 北京, 二钻, 北京西站/丽泽商务区, 39.896449, 116.317382, https://m.tuniucdn.com/fb3/s1/2n9c/42DTRnKbiYoiGFVzrV9ZJUxNbvRo_w200_h200_c1_t0.jpg);
- ② 引入依赖
elasticsearch相关依赖，如下：
<!--elasticsearch-->
<dependency>
<groupId>org.elasticsearch.client</groupId>
<artifactId>elasticsearch-rest-high-level-client</artifactId>
<version>7.12.1</version>
</dependency>
因为SpringBoot默认的ES版本是7.6.2，所以我们需要覆盖默认的ES版本：
<properties>
<!--指定我们所需的版本，覆盖springboot默认配置-->
<elasticsearch.version>7.12.1</elasticsearch.version>
</properties>
其他依赖，如下：
<!--web-->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<!--mybatis_plus-->
<dependency>
<groupId>com.baomidou</groupId>
<artifactId>mybatis-plus-boot-starter</artifactId>
<version>3.4.2</version>
</dependency>
<!--mysql_connector-->
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<scope>runtime</scope>
</dependency>
<!--lombok-->
<dependency>
<groupId>org.projectlombok</groupId>
<artifactId>lombok</artifactId>
<optional>true</optional>
</dependency>
<!--test-->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
<exclusions>
<exclusion>
<groupId>org.junit.vintage</groupId>
<artifactId>junit-vintage-engine</artifactId>
</exclusion>
</exclusions>
</dependency>
<!--FastJson-->
<dependency>
<groupId>com.alibaba</groupId>
<artifactId>fastjson</artifactId>
<version>1.2.71</version>
</dependency>
<!--commons-lang3:工具包-->
<dependency>
<groupId>org.apache.commons</groupId>
<artifactId>commons-lang3</artifactId>
</dependency>
- ③ application.yml
Ⅰ 配置服务端口；
Ⅱ 配置数据源；
Ⅲ 配置日志；
Ⅳ 配置mybatis-plus。
server:
port: 8089
spring:
datasource:
url: jdbc:mysql://localhost:3306/test?useSSL=false
username: root
password: root
driver-class-name: com.mysql.jdbc.Driver
logging:
level:
cn.test: debug
pattern:
dateformat: MM-dd HH:mm:ss:SSS
mybatis-plus:
configuration:
map-underscore-to-camel-case: true
type-aliases-package: cn.test.hotel.pojo
- ④ 编写实体类
Hotel类
@Data
@TableName("tb_hotel")
public class Hotel
@TableId(type = IdType.INPUT)
private Long id;
private String name;
private String address;
private Integer price;
private Integer score;
private String brand;
private String city;
private String starName;
private String business;
private String longitude;
private String latitude;
private String pic;
HotelDoc类
@Data
@NoArgsConstructor
public class HotelDoc
private Long id;
private String name;
private String address;
private Integer price;
private Integer score;
private String brand;
private String city;
private String starName;
private String business;
private String location;
private String pic;
public HotelDoc(Hotel hotel)
this.id = hotel.getId();
this.name = hotel.getName();
this.address = hotel.getAddress();
this.price = hotel.getPrice();
this.score = hotel.getScore();
this.brand = hotel.getBrand();
this.city = hotel.getCity();
this.starName = hotel.getStarName();
this.business = hotel.getBusiness();
this.location = hotel.getLatitude() + ", " + hotel.getLongitude();
this.pic = hotel.getPic();
geo_point类型属性映射的形式有多种，官方文档见此：Geopoint field type
，常见的形式如下图。此处我们采用第2种形式，做属性映射"location": "41.12,-71.34"，所以在类型转换的时候手动拼接了属性值this.location = hotel.getLatitude() + ", " + hotel.getLongitude();。
- ⑤ 编写mapper接口及service接口&实现类
public interface HotelMapper extends BaseMapper<Hotel>
public interface IHotelService extends IService<Hotel>
@Service
public class HotelService extends ServiceImpl<HotelMapper, Hotel> implements IHotelService
2、RestClient操作索引库
- ① 创建索引库
Ⅰ 编写创建索引库语句：这个步骤可以在自己Dev Tools控制台内完成，然后将字段复制到IDEA。
public class HotelConstant
public static final String MAPPING_TEMPLATE = "" +
"\\n" +
" \\"mappings\\": \\n" +
" \\"properties\\": \\n" +
" \\"id\\":\\n" +
" \\"type\\": \\"keyword\\"\\n" +
" ,\\n" +
" \\"name\\":\\n" +
" \\"type\\": \\"text\\",\\n" +
" \\"analyzer\\": \\"ik_max_word\\",\\n" +
" \\"copy_to\\": \\"all\\"\\n" +
" ,\\n" +
" \\"address\\":\\n" +
" \\"type\\": \\"keyword\\",\\n" +
" \\"index\\": false\\n" +
" ,\\n" +
" \\"price\\":\\n" +
" \\"type\\": \\"integer\\"\\n" +
" ,\\n" +
" \\"score\\":\\n" +
" \\"type\\": \\"integer\\"\\n" +
" ,\\n" +
" \\"brand\\":\\n" +
" \\"type\\": \\"keyword\\",\\n" +
" \\"copy_to\\": \\"all\\"\\n" +
" ,\\n" +
" \\"city\\":\\n" +
" \\"type\\": \\"keyword\\"\\n" +
" ,\\n" +
" \\"starName\\":\\n" +
" \\"type\\":\\"keyword\\"\\n" +
" ,\\n" +
" \\"business\\":\\n" +
" \\"type\\": \\"keyword\\",\\n" +
" \\"copy_to\\": \\"all\\"\\n" +
" ,\\n" +
" \\"location\\":\\n" +
" \\"type\\": \\"geo_point\\"\\n" +
" ,\\n" +
" \\"pic\\":\\n" +
" \\"type\\": \\"keyword\\",\\n" +
" \\"index\\": false\\n" +
" ,\\n" +
" \\"all\\":\\n" +
" \\"type\\": \\"text\\",\\n" +
" \\"analyzer\\": \\"ik_max_word\\"\\n" +
" \\n" +
" \\n" +
" \\n" +
"";
- ② 编写测试类
@BeforeEach内完成client对象的初始化配置，@AfterEach内完成操作后的资源释放。
public class HotelIndexTest
private RestHighLevelClient client;
@BeforeEach
void setUp()
this.client = new RestHighLevelClient(RestClient.builder(
HttpHost.create("http://192.168.253.128:9200")
));
... ...
@AfterEach
void tearDown()
try
this.client.close();
catch (IOException e)
e.printStackTrace();
- ③ 编写创建索引库方法
@Test
void createHotelIndex()
// 1. 创建Request对象
CreateIndexRequest request = new CreateIndexRequest("hotel");
// 2. 准备请求参数DSL语句
request.source(HotelConstant.MAPPING_TEMPLATE, XContentType.JSON);
// 3. 发送请求
try
client.indices().create(request, RequestOptions.DEFAULT);
catch (IOException e)
e.printStackTrace();
- ④ 编写删除索引库方法
@Test
void deleteHotelIndex()
// 1. 创建Request对象
DeleteIndexRequest request = new DeleteIndexRequest("hotel");
// 2. 发送请求
try
client.indices().delete(request, RequestOptions.DEFAULT);
catch (IOException e)
e.printStackTrace();
- ⑤ 编写判断是否存在索引库方法
@Test
void existsHotelIndex()
// 1. 创建Request对象
GetIndexRequest request = new GetIndexRequest("hotel");
// 2. 发送请求
try
boolean exists = client.indices().exists(request, RequestOptions.DEFAULT);
System.err.println(exists ? "hotel index exists!" : "hotel index not exist!");
catch (IOException e)
e.printStackTrace();
不难看出对索引库的操作有一定的相似性：
Ⅰ XXXIndexRequest：Create、Delete、Get的请求request对象；
Ⅱ client.indices().XXX()：create、delete、get方法。
3、RestClient操作文档
添加@SpringBootTest注解，注入hotelService：
@Resource
private IHotelService hotelService;
- ① 添加文档数据方法
@Test
void addDocument()
// 1. 查询数据库
Hotel hotel = hotelService.getById(36934L);
// 2. 封装成DOC对象
HotelDoc hotelDoc = new HotelDoc(hotel);
// 3. 获取request对象
IndexRequest request = new IndexRequest("hotel").id(hotel.getId().toString());
// 4. 将数据放入request
request.source(JSON.toJSONString(hotelDoc), XContentType.JSON);
// 5. 存储数据
try
client.index(request, RequestOptions.DEFAULT);
catch (IOException e)
e.printStackTrace();
- ② 获取文档数据方法
@Test
void getDocumentById()
// 1. 创建request对象
GetRequest request = new GetRequest("hotel", "36934");
try
// 2. 发送请求，得到结果
GetResponse response = client.get(request, RequestOptions.DEFAULT);
// 3. 解析结果
String json = response.getSourceAsString();
System.out.println(json);
catch (IOException e)
e.printStackTrace();
- ③ 更新文档数据方法
@Test
void updateDocumentById()
// 1. 创建request对象
UpdateRequest request = new UpdateRequest("hotel", "36934");
// 2. 设置更新字段
request.doc(
"price", "346",
"starName", "三钻"
);
// 3. 更新文档
try
client.update(request, RequestOptions.DEFAULT);
catch (IOException e)
e.printStackTrace();
- ④ 删除文档数方法
@Test
void deleteDocumentById()
// 1. 创建request对象
DeleteRequest request = new DeleteRequest("hotel", "36934");
// 2. 删除文档
try
client.delete(request, RequestOptions.DEFAULT);
catch (IOException e)
e.printStackTrace();
- ⑤ 批量操作方法
@Test
void bulkRequest()
// 1. 获取请求对象
BulkRequest request = new BulkRequest();
// 2. 准备参数，添加多个新增的Request
// 2.1 批量获取数据库的数据
List<Hotel> hotelList = hotelService.list();
for (int i = 0; i < hotelList.size(); i++)
// 2.2 获取hotel对象
Hotel hotel = hotelList.get(i);
// 2.3 转换成hotelDoc对象
HotelDoc hotelDoc = new HotelDoc(hotel);
/*// 2.4 获取request对象
IndexRequest indexRequest = new IndexRequest("hotel").id(hotel.getId().toString());
// 2.5 将数据放入request
indexRequest.source(JSON.toJSONString(hotelDoc), XContentType.JSON);
// 2.6 将indexRequest对象加入request
request.add(indexRequest);*/
request.add(new IndexRequest("hotel")
.id(hotelDoc.getId().toString())
.source(JSON.toJSONString(hotelDoc), XContentType.JSON));
// 3. 批量添加
try
client.bulk(request, RequestOptions.DEFAULT);
catch (IOException e)
e.printStackTrace();
不难看出对索引文档的操作也具有一定的相似性：
Ⅰ XXXRequest：Index、Get、Update、Delete、Bulk的请求request对象；
Ⅱ client.XXX(方法：index、get、update、delete、bulk方法。
三、结尾
以上即为RestClient基础的全部内容
线性基入门
线性基入门
简要讲解
xor下的线性基:
线性基求法:
从高位向低位求，如果控制i位的线性基存在，则a[k]^=p[i]
否则 p[i] = a[k];break;
进一步，将除线性基p[i]外的线性基的i位变为0；则得到元素最小的线性基；求第k小；
注意当元素存在冗余，则可以异或生成0；反之，不能生成0
将k进行2进制表示，则可对应相应的线性基进行异或线性基的概念类似于空间张成，即通过最少的元素能张成异或运算下的整个空间
参考博客
例题HDU3949
code
#include <bits/stdc++.h>
using namespace std;
#pragma GCC optimize("O3")
#define ll long long
#define ull unsigned long long
#define db(x) cout<<#x"=["<<(x)<<"]"<<endl
#define CL(a,b) memset(a,b,sizeof(a))
#define fast() ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0)
#define fr0(i,m) for(int i=0;i<m;i++)
#define fr1(i,m) for(int i=1;i<=m;i++)
//author:fridayfang
//date:19 7月 07
const double esp=1e-8;
const int mod=1e9+7;
const double pi=acos(-1);
const int inf=0x3f3f3f3f;
const int maxn = 1e4 + 5;
const int maxm = 1e6+5;
ll a[maxn];
ll p[64];
int to[100];//
ll t,n,q;
int getBase()//处理处理出线性基
CL(p,0);//先要清0
for(ll i=1;i<=n;i++)
for(int j=63;j>=0;j--)
if((a[i]>>j)&1)
if(!p[j])p[j] = a[i]; break;
a[i]^=p[j];
// 更小的线性基
int cnt = 0;
for(int j=0;j<=63;j++)
if(!p[j]) continue;
for(int i=j+1;i<=63;i++)
if((p[i]>>j)&1) p[i] = p[i]^p[j];
to[cnt++]=j;
return cnt;//cnt是线性基的个数 to[0]...to[cnt-1]有正确的映射
ll getK(ll k,int bound)//除0外的最k小
int t = 0;
ll tmp = k;
ll ans = 0;
while(tmp)
if(t>=bound) return -1;
if(tmp&1) ans^=p[to[t]];
tmp = tmp>>1;
t++;
return ans;
int main()
fast();cin>>t;
for(ll i=1;i<=t;i++)
cout<<"Case #"<<i<<":\\n";
cin>>n;
for(ll k=1;k<=n;k++) cin>>a[k];
int cnt = getBase();
int t = (cnt==(int)n)?0:1;//不等表示有冗余，则可表示0；此时第k小时第k-1小
cin>>q;
ll k;
for(ll s=1;s<=q;s++)
cin>>k; k-=t;
cout<<getK(k,cnt)<<endl;
return 0;
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