initial Commit

.gitignore

+HELP.md
+target/
+!.mvn/wrapper/maven-wrapper.jar
+!**/src/main/**/target/
+!**/src/test/**/target/
+
+### STS ###
+.apt_generated
+.classpath
+.factorypath
+.project
+.settings
+.springBeans
+.sts4-cache
+
+### IntelliJ IDEA ###
+.idea
+*.iws
+*.iml
+*.ipr
+
+### NetBeans ###
+/nbproject/private/
+/nbbuild/
+/dist/
+/nbdist/
+/.nb-gradle/
+build/
+!**/src/main/**/build/
+!**/src/test/**/build/
+
+### VS Code ###
+.vscode/

.mvn/wrapper/maven-wrapper.properties

+distributionUrl=https://repo.maven.apache.org/maven2/org/apache/maven/apache-maven/3.8.6/apache-maven-3.8.6-bin.zip
+wrapperUrl=https://repo.maven.apache.org/maven2/org/apache/maven/wrapper/maven-wrapper/3.1.0/maven-wrapper-3.1.0.jar

mvnw.cmd

+@REM ----------------------------------------------------------------------------
+@REM Licensed to the Apache Software Foundation (ASF) under one
+@REM or more contributor license agreements.  See the NOTICE file
+@REM distributed with this work for additional information
+@REM regarding copyright ownership.  The ASF licenses this file
+@REM to you under the Apache License, Version 2.0 (the
+@REM "License"); you may not use this file except in compliance
+@REM with the License.  You may obtain a copy of the License at
+@REM
+@REM    https://www.apache.org/licenses/LICENSE-2.0
+@REM
+@REM Unless required by applicable law or agreed to in writing,
+@REM software distributed under the License is distributed on an
+@REM "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+@REM KIND, either express or implied.  See the License for the
+@REM specific language governing permissions and limitations
+@REM under the License.
+@REM ----------------------------------------------------------------------------
+
+@REM ----------------------------------------------------------------------------
+@REM Maven Start Up Batch script
+@REM
+@REM Required ENV vars:
+@REM JAVA_HOME - location of a JDK home dir
+@REM
+@REM Optional ENV vars
+@REM M2_HOME - location of maven2's installed home dir
+@REM MAVEN_BATCH_ECHO - set to 'on' to enable the echoing of the batch commands
+@REM MAVEN_BATCH_PAUSE - set to 'on' to wait for a keystroke before ending
+@REM MAVEN_OPTS - parameters passed to the Java VM when running Maven
+@REM     e.g. to debug Maven itself, use
+@REM set MAVEN_OPTS=-Xdebug -Xrunjdwp:transport=dt_socket,server=y,suspend=y,address=8000
+@REM MAVEN_SKIP_RC - flag to disable loading of mavenrc files
+@REM ----------------------------------------------------------------------------
+
+@REM Begin all REM lines with '@' in case MAVEN_BATCH_ECHO is 'on'
+@echo off
+@REM set title of command window
+title %0
+@REM enable echoing by setting MAVEN_BATCH_ECHO to 'on'
+@if "%MAVEN_BATCH_ECHO%" == "on"  echo %MAVEN_BATCH_ECHO%
+
+@REM set %HOME% to equivalent of $HOME
+if "%HOME%" == "" (set "HOME=%HOMEDRIVE%%HOMEPATH%")
+
+@REM Execute a user defined script before this one
+if not "%MAVEN_SKIP_RC%" == "" goto skipRcPre
+@REM check for pre script, once with legacy .bat ending and once with .cmd ending
+if exist "%USERPROFILE%\mavenrc_pre.bat" call "%USERPROFILE%\mavenrc_pre.bat" %*
+if exist "%USERPROFILE%\mavenrc_pre.cmd" call "%USERPROFILE%\mavenrc_pre.cmd" %*
+:skipRcPre
+
+@setlocal
+
+set ERROR_CODE=0
+
+@REM To isolate internal variables from possible post scripts, we use another setlocal
+@setlocal
+
+@REM ==== START VALIDATION ====
+if not "%JAVA_HOME%" == "" goto OkJHome
+
+echo.
+echo Error: JAVA_HOME not found in your environment. >&2
+echo Please set the JAVA_HOME variable in your environment to match the >&2
+echo location of your Java installation. >&2
+echo.
+goto error
+
+:OkJHome
+if exist "%JAVA_HOME%\bin\java.exe" goto init
+
+echo.
+echo Error: JAVA_HOME is set to an invalid directory. >&2
+echo JAVA_HOME = "%JAVA_HOME%" >&2
+echo Please set the JAVA_HOME variable in your environment to match the >&2
+echo location of your Java installation. >&2
+echo.
+goto error
+
+@REM ==== END VALIDATION ====
+
+:init
+
+@REM Find the project base dir, i.e. the directory that contains the folder ".mvn".
+@REM Fallback to current working directory if not found.
+
+set MAVEN_PROJECTBASEDIR=%MAVEN_BASEDIR%
+IF NOT "%MAVEN_PROJECTBASEDIR%"=="" goto endDetectBaseDir
+
+set EXEC_DIR=%CD%
+set WDIR=%EXEC_DIR%
+:findBaseDir
+IF EXIST "%WDIR%"\.mvn goto baseDirFound
+cd ..
+IF "%WDIR%"=="%CD%" goto baseDirNotFound
+set WDIR=%CD%
+goto findBaseDir
+
+:baseDirFound
+set MAVEN_PROJECTBASEDIR=%WDIR%
+cd "%EXEC_DIR%"
+goto endDetectBaseDir
+
+:baseDirNotFound
+set MAVEN_PROJECTBASEDIR=%EXEC_DIR%
+cd "%EXEC_DIR%"
+
+:endDetectBaseDir
+
+IF NOT EXIST "%MAVEN_PROJECTBASEDIR%\.mvn\jvm.config" goto endReadAdditionalConfig
+
+@setlocal EnableExtensions EnableDelayedExpansion
+for /F "usebackq delims=" %%a in ("%MAVEN_PROJECTBASEDIR%\.mvn\jvm.config") do set JVM_CONFIG_MAVEN_PROPS=!JVM_CONFIG_MAVEN_PROPS! %%a
+@endlocal & set JVM_CONFIG_MAVEN_PROPS=%JVM_CONFIG_MAVEN_PROPS%
+
+:endReadAdditionalConfig
+
+SET MAVEN_JAVA_EXE="%JAVA_HOME%\bin\java.exe"
+set WRAPPER_JAR="%MAVEN_PROJECTBASEDIR%\.mvn\wrapper\maven-wrapper.jar"
+set WRAPPER_LAUNCHER=org.apache.maven.wrapper.MavenWrapperMain
+
+set DOWNLOAD_URL="https://repo.maven.apache.org/maven2/org/apache/maven/wrapper/maven-wrapper/3.1.0/maven-wrapper-3.1.0.jar"
+
+FOR /F "usebackq tokens=1,2 delims==" %%A IN ("%MAVEN_PROJECTBASEDIR%\.mvn\wrapper\maven-wrapper.properties") DO (
+    IF "%%A"=="wrapperUrl" SET DOWNLOAD_URL=%%B
+)
+
+@REM Extension to allow automatically downloading the maven-wrapper.jar from Maven-central
+@REM This allows using the maven wrapper in projects that prohibit checking in binary data.
+if exist %WRAPPER_JAR% (
+    if "%MVNW_VERBOSE%" == "true" (
+        echo Found %WRAPPER_JAR%
+    )
+) else (
+    if not "%MVNW_REPOURL%" == "" (
+        SET DOWNLOAD_URL="%MVNW_REPOURL%/org/apache/maven/wrapper/maven-wrapper/3.1.0/maven-wrapper-3.1.0.jar"
+    )
+    if "%MVNW_VERBOSE%" == "true" (
+        echo Couldn't find %WRAPPER_JAR%, downloading it ...
+        echo Downloading from: %DOWNLOAD_URL%
+    )
+
+    powershell -Command "&{"^
+		"$webclient = new-object System.Net.WebClient;"^
+		"if (-not ([string]::IsNullOrEmpty('%MVNW_USERNAME%') -and [string]::IsNullOrEmpty('%MVNW_PASSWORD%'))) {"^
+		"$webclient.Credentials = new-object System.Net.NetworkCredential('%MVNW_USERNAME%', '%MVNW_PASSWORD%');"^
+		"}"^
+		"[Net.ServicePointManager]::SecurityProtocol = [Net.SecurityProtocolType]::Tls12; $webclient.DownloadFile('%DOWNLOAD_URL%', '%WRAPPER_JAR%')"^
+		"}"
+    if "%MVNW_VERBOSE%" == "true" (
+        echo Finished downloading %WRAPPER_JAR%
+    )
+)
+@REM End of extension
+
+@REM Provide a "standardized" way to retrieve the CLI args that will
+@REM work with both Windows and non-Windows executions.
+set MAVEN_CMD_LINE_ARGS=%*
+
+%MAVEN_JAVA_EXE% ^
+  %JVM_CONFIG_MAVEN_PROPS% ^
+  %MAVEN_OPTS% ^
+  %MAVEN_DEBUG_OPTS% ^
+  -classpath %WRAPPER_JAR% ^
+  "-Dmaven.multiModuleProjectDirectory=%MAVEN_PROJECTBASEDIR%" ^
+  %WRAPPER_LAUNCHER% %MAVEN_CONFIG% %*
+if ERRORLEVEL 1 goto error
+goto end
+
+:error
+set ERROR_CODE=1
+
+:end
+@endlocal & set ERROR_CODE=%ERROR_CODE%
+
+if not "%MAVEN_SKIP_RC%"=="" goto skipRcPost
+@REM check for post script, once with legacy .bat ending and once with .cmd ending
+if exist "%USERPROFILE%\mavenrc_post.bat" call "%USERPROFILE%\mavenrc_post.bat"
+if exist "%USERPROFILE%\mavenrc_post.cmd" call "%USERPROFILE%\mavenrc_post.cmd"
+:skipRcPost
+
+@REM pause the script if MAVEN_BATCH_PAUSE is set to 'on'
+if "%MAVEN_BATCH_PAUSE%"=="on" pause
+
+if "%MAVEN_TERMINATE_CMD%"=="on" exit %ERROR_CODE%
+
+cmd /C exit /B %ERROR_CODE%

pom.xml

+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+	xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
+	<modelVersion>4.0.0</modelVersion>
+	<parent>
+		<groupId>org.springframework.boot</groupId>
+		<artifactId>spring-boot-starter-parent</artifactId>
+		<version>3.0.1</version>
+		<relativePath/> <!-- lookup parent from repository -->
+	</parent>
+	<groupId>com.nisum.poc</groupId>
+	<artifactId>Webflux</artifactId>
+	<version>0.0.1-SNAPSHOT</version>
+	<name>Webflux</name>
+	<description>Demo project for Spring Boot webFlux</description>
+	<properties>
+		<java.version>17</java.version>
+	</properties>
+	<dependencies>
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-starter-data-mongodb-reactive</artifactId>
+		</dependency>
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-starter-webflux</artifactId>
+		</dependency>
+
+		<dependency>
+			<groupId>org.projectlombok</groupId>
+			<artifactId>lombok</artifactId>
+			<optional>true</optional>
+		</dependency>
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-starter-test</artifactId>
+			<scope>test</scope>
+		</dependency>
+		<dependency>
+			<groupId>io.projectreactor</groupId>
+			<artifactId>reactor-test</artifactId>
+			<scope>test</scope>
+		</dependency>
+	</dependencies>
+
+	<build>
+		<plugins>
+			<plugin>
+				<groupId>org.springframework.boot</groupId>
+				<artifactId>spring-boot-maven-plugin</artifactId>
+				<configuration>
+					<excludes>
+						<exclude>
+							<groupId>org.projectlombok</groupId>
+							<artifactId>lombok</artifactId>
+						</exclude>
+					</excludes>
+				</configuration>
+			</plugin>
+		</plugins>
+	</build>
+
+</project>

src/main/java/com/nisum/poc/Webflux/WebFluxApplication.java

+package com.nisum.poc.Webflux;
+
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+import org.springframework.boot.autoconfigure.domain.EntityScan;
+import org.springframework.context.annotation.ComponentScan;
+import org.springframework.data.mongodb.repository.config.EnableReactiveMongoRepositories;
+import org.springframework.stereotype.Component;
+
+@SpringBootApplication
+@ComponentScan(basePackages = "com.nisum")
+@EntityScan("com.nisum.poc")
+//@EnableReactiveMongoRepositories(basePackages = "com.nisum.poc")
+public class WebFluxApplication {
+
+	public static void main(String[] args) {
+		SpringApplication.run(WebFluxApplication.class, args);
+	}
+
+}

src/main/java/com/nisum/poc/Webflux/config/MongoDBConfiguration.java

+package com.nisum.poc.Webflux.config;
+
+import com.mongodb.reactivestreams.client.MongoClient;
+import com.mongodb.reactivestreams.client.MongoClients;
+import org.springframework.beans.factory.annotation.Value;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.data.mongodb.config.AbstractReactiveMongoConfiguration;
+import org.springframework.data.mongodb.core.ReactiveMongoTemplate;
+import org.springframework.data.mongodb.repository.config.EnableMongoRepositories;
+import org.springframework.data.mongodb.repository.config.EnableReactiveMongoRepositories;
+
+@Configuration
+@EnableReactiveMongoRepositories(basePackages = "com.nisum")
+public class MongoDBConfiguration extends AbstractReactiveMongoConfiguration {
+
+
+    @Value("${db.name}")
+    private String dbname;
+
+    @Value("${db.host}")
+    private String dbHost;
+
+
+    @Override
+    public MongoClient reactiveMongoClient() {
+        return MongoClients.create();
+    }
+    @Override
+    protected String getDatabaseName() {
+        return dbname ;
+    }
+    @Bean
+    public ReactiveMongoTemplate reactiveMongoTemplate(){
+        return new ReactiveMongoTemplate(reactiveMongoClient(),getDatabaseName());
+
+    }
+}

src/main/java/com/nisum/poc/Webflux/config/WebFluxConfig.java

+package com.nisum.poc.Webflux.config;
+
+import org.springframework.context.annotation.Configuration;
+import org.springframework.stereotype.Component;
+import org.springframework.web.reactive.config.EnableWebFlux;
+import org.springframework.web.reactive.config.WebFluxConfigurer;
+
+@Configuration
+@EnableWebFlux
+public class WebFluxConfig implements WebFluxConfigurer {
+}

src/main/java/com/nisum/poc/Webflux/config/WebclientEx.java

+package com.nisum.poc.Webflux.config;
+
+import com.nisum.poc.Webflux.entity.Student;
+import io.netty.handler.codec.http.websocketx.extensions.compression.WebSocketClientCompressionHandler;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.http.MediaType;
+import org.springframework.web.reactive.function.client.WebClient;
+import reactor.core.publisher.Flux;
+
+@Configuration
+public class WebclientEx {
+
+    WebClient client = WebClient.create("http://localhost:4042");
+    public Flux<Student> getAllStudents(){
+        return client.get().uri("/allStudents").accept(MediaType.APPLICATION_JSON).retrieve().bodyToFlux(Student.class);
+    }
+}

src/main/java/com/nisum/poc/Webflux/controller/AddressController.java

+package com.nisum.poc.Webflux.controller;
+
+import com.nisum.poc.Webflux.entity.Address;
+import com.nisum.poc.Webflux.model.AddressPayload;
+import com.nisum.poc.Webflux.service.IAddressService;
+import lombok.extern.slf4j.Slf4j;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.PostMapping;
+import org.springframework.web.bind.annotation.RequestBody;
+import org.springframework.web.bind.annotation.RestController;
+import reactor.core.publisher.Flux;
+import reactor.core.publisher.Mono;
+
+@RestController
+public class AddressController {
+    @Autowired
+    IAddressService addressService;
+
+
+    @PostMapping("/saveaddress")
+    public Mono<Address> createAddress(@RequestBody Address address){
+        return addressService.createAddress(address);
+
+    }
+
+    @GetMapping("/alladdress")
+    public Flux<Address> getAllAddress(){
+        return addressService.getAllAddress();
+
+    }
+}

src/main/java/com/nisum/poc/Webflux/controller/StudentController.java

+package com.nisum.poc.Webflux.controller;
+
+import com.nisum.poc.Webflux.entity.Student;
+import com.nisum.poc.Webflux.entity.Subject;
+import com.nisum.poc.Webflux.model.StudentPayload;
+import com.nisum.poc.Webflux.service.IStudentService;
+import com.nisum.poc.Webflux.service.ISubjectsService;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.PostMapping;
+import org.springframework.web.bind.annotation.RequestBody;
+import org.springframework.web.bind.annotation.RestController;
+import reactor.core.publisher.Flux;
+import reactor.core.publisher.Mono;
+
+import java.time.Duration;
+import java.util.Arrays;
+import java.util.List;
+
+@RestController
+public class StudentController {
+
+    @Autowired
+    IStudentService studentService;
+
+    @PostMapping("/saveStudent")
+    public Mono<Student> creatStudent(@RequestBody Student student){
+        return studentService.createStudent(student);
+
+    }
+
+    @GetMapping("/allStudents")
+    public Flux<StudentPayload> getAllStudents(){
+        return studentService.getAllStudents();
+
+    }
+    @GetMapping("/concatEx")
+    public  Flux<String> concatFlux(){
+        return studentService.concat();
+
+    }
+
+    @GetMapping("/mergeEx")
+    public  Flux<String> mergeFlux(){
+        return studentService.merge().log();
+
+    }
+    @GetMapping("/zipEx")
+    public  Flux<Integer> zip(){
+        return studentService.combineWithZip();
+    }
+
+    @GetMapping("/zipWithEx")
+    public  Flux<Integer> zipWith(){
+        Flux<Integer> evenNumbers = Flux
+                .range(1, 5)
+                .filter(x -> x % 2 == 0); // i.e. 2, 4
+
+        Flux<Integer> oddNumbers = Flux
+                .range(1, 5)
+                .filter(x -> x % 2 > 0);//1,3,5
+        Flux<Integer> concatIntegers = Flux.concat(evenNumbers,oddNumbers);
+        Flux<Integer> mergefIntegers = Flux.merge(evenNumbers,oddNumbers);
+        Flux<Integer> zipIntegers = Flux.zip(evenNumbers,oddNumbers,(a,b)->a*b).log();
+        //flux to mono last(),next(),elementAt(1), haselements() haselement(1),
+        Mono<Integer> integerMono = oddNumbers.next();
+        Flux<Integer> zipwithIntegers = evenNumbers.zipWith(oddNumbers,(a,b)->a*b);//2,12
+        return zipwithIntegers;
+    }
+
+    @GetMapping("/flatMap")
+    public Flux<String> transformUsingFlatMap() {
+        List<String> names = Arrays.asList("google ", "abc", "fb", " stackoverflow"," bhanuchander"," reddy");
+        Flux<String> namess = Flux.fromIterable(names).filter(name -> name.length() >= 5).flatMap(name -> {
+            return Flux.just(name.toUpperCase()).
+                    delayElements(Duration.ofMillis(151)).log();
+        });
+        return namess;
+    }
+}

src/main/java/com/nisum/poc/Webflux/controller/SubjectsController.java

+package com.nisum.poc.Webflux.controller;
+
+import com.nisum.poc.Webflux.entity.Address;
+import com.nisum.poc.Webflux.entity.Subject;
+import com.nisum.poc.Webflux.service.ISubjectsService;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.PostMapping;
+import org.springframework.web.bind.annotation.RequestBody;
+import org.springframework.web.bind.annotation.RestController;
+import reactor.core.publisher.Flux;
+import reactor.core.publisher.Mono;
+
+@RestController
+public class SubjectsController {
+
+    @Autowired
+    ISubjectsService subjectsService;
+
+    @PostMapping("/savesubject")
+    public Mono<Subject> creatSubject(@RequestBody Subject subject){
+        return subjectsService.createSuject(subject);
+
+    }
+
+    @GetMapping("/allsubjects")
+    public Flux<Subject> getAllSubjects(){
+        return subjectsService.getAllSubjects();
+
+    }
+
+}

src/main/java/com/nisum/poc/Webflux/entity/Address.java

+package com.nisum.poc.Webflux.entity;
+
+import lombok.*;
+import org.springframework.context.annotation.Scope;
+import org.springframework.context.annotation.ScopedProxyMode;
+import org.springframework.data.annotation.Id;
+import org.springframework.data.annotation.Transient;
+import org.springframework.data.mongodb.core.mapping.Document;
+
+@AllArgsConstructor
+@NoArgsConstructor
+@Setter
+@Getter
+@Document
+@Builder
+//@Scope(scopeName="request",proxyMode = ScopedProxyMode.TARGET_CLASS)
+public class Address {
+
+    @Transient
+    public static final String SEQUENCE_NAME = "users_sequence";
+    @Id
+    private Long id;
+    private String address;
+    private String city;
+    private String pinCode;
+    private String addressType;
+    private Long studentId;
+}

src/main/java/com/nisum/poc/Webflux/entity/Student.java

+package com.nisum.poc.Webflux.entity;
+
+import lombok.*;
+import org.springframework.context.annotation.Scope;
+import org.springframework.context.annotation.ScopedProxyMode;
+import org.springframework.data.annotation.Id;
+import org.springframework.data.annotation.Transient;
+import org.springframework.data.mongodb.core.mapping.Document;
+
+import java.util.List;
+
+@Document
+@AllArgsConstructor
+@NoArgsConstructor
+@Setter
+@Getter
+@Builder
+//@Scope(scopeName="request",proxyMode = ScopedProxyMode.TARGET_CLASS)
+public class Student {
+
+    @Transient
+    public static final String SEQUENCE_NAME = "users_sequence";
+    @Id
+    private Long id;
+    private String firstName;
+    private String lastName;
+    private Integer age;
+    private List<String> phoneNumbers;
+    private List<Address> address;
+    private List<Subject> subjects;
+
+}

src/main/java/com/nisum/poc/Webflux/entity/Subject.java

+package com.nisum.poc.Webflux.entity;
+
+import lombok.AllArgsConstructor;
+import lombok.Builder;
+import lombok.Data;
+import lombok.NoArgsConstructor;
+import org.springframework.context.annotation.Scope;
+import org.springframework.context.annotation.ScopedProxyMode;
+import org.springframework.data.annotation.Id;
+import org.springframework.data.annotation.Transient;
+import org.springframework.data.mongodb.core.mapping.Document;
+
+@AllArgsConstructor
+@NoArgsConstructor
+@Data
+@Document
+@Builder
+//@Scope(scopeName="request",proxyMode = ScopedProxyMode.TARGET_CLASS)
+public class Subject {
+
+    @Transient
+    public static final String SEQUENCE_NAME = "users_sequence";
+    @Id
+    private Long id;
+    private String subjectName;
+    private Long studentId;
+
+
+}

src/main/java/com/nisum/poc/Webflux/model/AddressPayload.java

+package com.nisum.poc.Webflux.model;
+
+import lombok.AllArgsConstructor;
+import lombok.Data;
+import lombok.NoArgsConstructor;
+
+@Data
+@AllArgsConstructor
+@NoArgsConstructor
+public class AddressPayload {
+    private Integer id;
+    private String address;
+    private String city;
+    private String pinCode;
+    private String addressType;
+    private Long studentId;
+}

src/main/java/com/nisum/poc/Webflux/model/StudentPayload.java

+package com.nisum.poc.Webflux.model;
+
+
+import com.nisum.poc.Webflux.entity.Address;
+import com.nisum.poc.Webflux.entity.Subject;
+import lombok.AllArgsConstructor;
+import lombok.Data;
+import lombok.NoArgsConstructor;
+import org.springframework.data.mongodb.core.aggregation.ArrayOperators;
+
+import java.util.List;
+
+@Data
+@AllArgsConstructor
+@NoArgsConstructor
+public class StudentPayload {
+    private Long id;
+    private String firstName;
+    private String lastName;
+    private Integer age;
+    private List<String> phoneNumbers;
+    private List<Address> addresses;
+    private List<Subject> subjects;
+}

src/main/java/com/nisum/poc/Webflux/model/SubjectPayload.java

+package com.nisum.poc.Webflux.model;
+
+import lombok.AllArgsConstructor;
+import lombok.Data;
+import lombok.NoArgsConstructor;
+
+@Data
+@AllArgsConstructor
+@NoArgsConstructor
+public class SubjectPayload {
+
+    private Integer id;
+    private String subjectName;
+    private Long studentId;
+
+}

src/main/java/com/nisum/poc/Webflux/repository/AddressRepository.java

+package com.nisum.poc.Webflux.repository;
+
+import com.nisum.poc.Webflux.entity.Address;
+import org.springframework.data.mongodb.repository.ReactiveMongoRepository;
+import org.springframework.stereotype.Repository;
+import reactor.core.publisher.Flux;
+
+@Repository
+public interface AddressRepository extends ReactiveMongoRepository<Address, Long> {
+
+    Flux<Address> findByStudentId(Long studentId);
+}

src/main/java/com/nisum/poc/Webflux/repository/StudentRepository.java

+package com.nisum.poc.Webflux.repository;
+
+import org.springframework.data.mongodb.repository.ReactiveMongoRepository;
+import com.nisum.poc.Webflux.entity.Student;
+import org.springframework.stereotype.Repository;
+
+@Repository
+public interface StudentRepository extends ReactiveMongoRepository<Student,Long> {
+}

src/main/java/com/nisum/poc/Webflux/repository/SubjectRepository.java

+package com.nisum.poc.Webflux.repository;
+
+import com.nisum.poc.Webflux.entity.Address;
+import com.nisum.poc.Webflux.entity.Subject;
+import org.springframework.data.mongodb.repository.ReactiveMongoRepository;
+import org.springframework.stereotype.Repository;
+import reactor.core.publisher.Flux;
+
+@Repository
+public interface SubjectRepository extends ReactiveMongoRepository<Subject,Long> {
+    Flux<Subject> findByStudentId(Long subjectId);
+
+}

src/main/java/com/nisum/poc/Webflux/service/IAddressService.java

+package com.nisum.poc.Webflux.service;
+
+import com.nisum.poc.Webflux.entity.Address;
+import com.nisum.poc.Webflux.model.AddressPayload;
+import org.springframework.stereotype.Service;
+import reactor.core.publisher.Flux;
+import reactor.core.publisher.Mono;
+
+@Service
+public interface IAddressService {
+    Mono<Address> createAddress(Address address);
+
+    Flux<Address> getAllAddress();
+}

src/main/java/com/nisum/poc/Webflux/service/IStudentService.java

+package com.nisum.poc.Webflux.service;
+
+import com.nisum.poc.Webflux.entity.Student;
+import com.nisum.poc.Webflux.entity.Subject;
+import com.nisum.poc.Webflux.model.StudentPayload;
+import org.springframework.stereotype.Repository;
+import org.springframework.stereotype.Service;
+import reactor.core.publisher.Flux;
+import reactor.core.publisher.Mono;
+
+@Service
+public interface IStudentService {
+
+    Mono<Student> createStudent(Student student);
+
+    Flux<StudentPayload> getAllStudents();
+    Flux<String> concat();
+
+    Flux<String> merge();
+    public Flux<Integer> combineWithZip();
+}

src/main/java/com/nisum/poc/Webflux/service/ISubjectsService.java

+package com.nisum.poc.Webflux.service;
+
+import com.nisum.poc.Webflux.entity.Address;
+import com.nisum.poc.Webflux.entity.Subject;
+import org.springframework.stereotype.Service;
+import reactor.core.publisher.Flux;
+import reactor.core.publisher.Mono;
+
+@Service
+public interface ISubjectsService {
+    Mono<Subject> createSuject(Subject subject);
+
+    Flux<Subject> getAllSubjects();
+}

src/main/java/com/nisum/poc/Webflux/service/impl/AddressServiceImpl.java

+package com.nisum.poc.Webflux.service.impl;
+
+import com.nisum.poc.Webflux.entity.Address;
+import com.nisum.poc.Webflux.repository.AddressRepository;
+import com.nisum.poc.Webflux.service.IAddressService;
+import lombok.extern.slf4j.Slf4j;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.stereotype.Service;
+import reactor.core.publisher.Flux;
+import reactor.core.publisher.Mono;
+
+@Service
+@Slf4j
+public class AddressServiceImpl implements IAddressService {
+
+    @Autowired
+    AddressRepository addressRepository;
+    @Override
+    public Mono<Address> createAddress(Address address) {
+        return addressRepository.save(address);
+
+    }
+
+    @Override
+    public Flux<Address> getAllAddress() {
+        return addressRepository.findAll();
+    }
+}

src/main/java/com/nisum/poc/Webflux/service/impl/StudentServiceImpl.java

+package com.nisum.poc.Webflux.service.impl;
+
+import com.nisum.poc.Webflux.entity.Address;
+import com.nisum.poc.Webflux.entity.Student;
+import com.nisum.poc.Webflux.entity.Subject;
+import com.nisum.poc.Webflux.model.StudentPayload;
+import com.nisum.poc.Webflux.repository.AddressRepository;
+import com.nisum.poc.Webflux.repository.StudentRepository;
+import com.nisum.poc.Webflux.repository.SubjectRepository;
+import com.nisum.poc.Webflux.service.IStudentService;
+import lombok.extern.slf4j.Slf4j;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.stereotype.Service;
+import reactor.core.publisher.Flux;
+import reactor.core.publisher.Mono;
+import reactor.util.function.Tuple2;
+
+import java.util.ArrayList;
+import java.util.List;
+
+
+@Service
+@Slf4j
+public class StudentServiceImpl implements IStudentService {
+
+
+    @Autowired
+    StudentRepository studentRepository;
+    @Autowired
+    AddressRepository addressRepository;
+    @Autowired
+    SubjectRepository subjectRepository;
+    @Override
+    public Mono<Student> createStudent(Student student) {
+        Student student1 = new Student();
+        student1.setId(student.getId());
+        student1.setAge(student.getAge());
+        student1.setFirstName(student.getFirstName());
+        student1.setLastName(student.getLastName());
+        student1.setPhoneNumbers(student.getPhoneNumbers());
+        Mono<Student> studentMono = studentRepository.save(student1);
+
+        List<Address> addressList = new ArrayList<>();
+        List<Subject> subjectList = new ArrayList<>();
+
+        studentMono.subscribe(studentmono -> {
+            student.getAddress().forEach(address -> {
+                Address address1 = new Address();
+                address1.setId(address.getId());
+                address1.setAddress(address.getAddress());
+                address1.setStudentId(studentmono.getId());
+                address1.setCity(address.getCity());
+                address1.setAddressType(address.getAddressType());
+                address1.setPinCode(address.getPinCode());
+                addressList.add(address1);
+            });
+            student.getSubjects().forEach(sub -> {
+                Subject subject = new Subject();
+                subject.setId(sub.getId());
+                subject.setSubjectName(sub.getSubjectName());
+                subject.setStudentId(studentmono.getId());
+                subjectList.add(subject);
+            });
+            Flux<Address> addressFlux = addressRepository.saveAll(addressList);
+            Flux<Subject> subjectFlux = subjectRepository.saveAll(subjectList);
+        });
+        return studentMono;
+    }
+    @Override
+    public Flux<StudentPayload> getAllStudents() {
+       return studentRepository.findAll().flatMap(student -> {
+             Flux<Address> addressFlux = addressRepository.findByStudentId(student.getId()).switchIfEmpty(Flux.just(new Address()));
+             Flux<Subject> subjectFlux = subjectRepository.findByStudentId(student.getId()).switchIfEmpty(Flux.just(new Subject()));
+             StudentPayload studentPayload = new StudentPayload();
+             studentPayload.setId(student.getId());
+             studentPayload.setAge(student.getAge());
+             studentPayload.setPhoneNumbers(student.getPhoneNumbers());
+             studentPayload.setFirstName(student.getFirstName());
+             studentPayload.setLastName(student.getLastName());
+             studentPayload.setAddresses(addressFlux.collectList().block());
+             studentPayload.setSubjects(subjectFlux.collectList().block());
+             Flux<StudentPayload> studentPayloadFlux = Flux.just(studentPayload);
+             return studentPayloadFlux;
+         });
+       // return studentFlux;
+    }
+
+    public Flux<String> concat() {
+        Flux<String> names1 = Flux.just("Hi ", " Hello ", "how ");
+        Flux<String> names2 = Flux.just("are ", " you ", " Doing");
+        Flux<String> names = Flux.concat(names1, names2).log();
+        return names;
+    }
+
+    public Flux<String> merge() {
+        Flux<String> names1 = Flux.just("Hi ", " Hello ", "how ");
+        Flux<String> names2 = Flux.just("are ", " you ", " Doing");
+        Flux<String> names = Flux.merge(names1, names2).log();
+        return names;
+    }
+
+    public Flux<Integer> combineWithZip(){
+
+        Flux<Integer> name1 = Flux.just(1, 2, 3);
+        Flux<Integer> name2 = Flux.just(4,5,6);
+        Flux<Integer> name3 = Flux.zip(name1,name2,(n1, n2)->{
+            return n1*n2;
+        });
+        return name3;
+    }
+    public Mono<String> combineWithZipChara(){
+
+        Mono<String> name1 = Mono.just("Hi");
+        Mono<String> name2 = Mono.just("are");
+        Flux<String> name3 = Mono.zip(name1,name2).flatMap(a ->{
+            a.getT1().toString();
+        });
+
+    }
+
+}

src/main/java/com/nisum/poc/Webflux/service/impl/SubjectsServiceImpl.java

+package com.nisum.poc.Webflux.service.impl;
+
+import com.nisum.poc.Webflux.entity.Address;
+import com.nisum.poc.Webflux.entity.Subject;
+import com.nisum.poc.Webflux.repository.SubjectRepository;
+import com.nisum.poc.Webflux.service.ISubjectsService;
+import lombok.extern.slf4j.Slf4j;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.stereotype.Service;
+import reactor.core.publisher.Flux;
+import reactor.core.publisher.Mono;
+
+@Service
+@Slf4j
+public class SubjectsServiceImpl implements ISubjectsService {
+
+    @Autowired
+    SubjectRepository subjectRepository;
+    @Override
+    public Mono<Subject> createSuject(Subject subject) {
+        return subjectRepository.save(subject);
+    }
+
+    @Override
+    public Flux<Subject> getAllSubjects() {
+        return subjectRepository.findAll();
+    }
+}

src/main/resources/application.properties

+db.name=StudentDatabase
+db.host=mongodb://localhost:27017
+server.port=4042

src/test/java/com/nisum/poc/Webflux/WebfluxApplicationTests.java

+package com.nisum.poc.Webflux;
+
+import org.junit.jupiter.api.Test;
+import org.springframework.boot.test.context.SpringBootTest;
+
+@SpringBootTest
+class WebfluxApplicationTests {
+
+	@Test
+	void contextLoads() {
+	}
+
+}