Micronaut + React JS + MongoDB CRUD Example

Hello everyone, today we will learn how to develop a full-stack web application that is a basic User Management Application using Micronaut, React and MongoDB.
GitHub repository link is provided at the end of this tutorial. You can download the source code.

After completing this tutorial what we will build? 

We will build a full-stack web application that is a basic User Management Application with CRUD features:

• Create User
• List User
• Update User 
• Delete User 


Add User:


View All Users:


Update User:


View User:



We divided this tutorial into two parts. 

PART 1 - Rest APIs Development using Micronaut
PART 2 - UI development using React.js

 PART 1 - Rest APIs Development using Micronaut 

Project Directory:



Maven[pom.xml]

A Project Object Model or POM is the fundamental unit of work in Maven. It is an XML file that contains information about the project and configuration details utilized by Maven to build the project. It contains default values for most projects. Some of the configurations that can be designated in the POM is the project dependencies, the plugins or goals that can be executed, the build profiles, and so on. Other information such as the project version, description, developers, mailing lists and such can withal be designated.
<?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 
    http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <groupId>com.knf.dev.demo</groupId>
    <artifactId>micronaut-mongodb-crud</artifactId>
    <version>0.1</version>
    <packaging>${packaging}</packaging>

    <parent>
        <groupId>io.micronaut</groupId>
        <artifactId>micronaut-parent</artifactId>
        <version>3.1.1</version>
    </parent>

    <properties>
        <packaging>jar</packaging>
        <jdk.version>11</jdk.version>
        <release.version>11</release.version>
        <micronaut.version>3.1.1</micronaut.version>
        <exec.mainClass>com.knf.dev.demo.Application
              </exec.mainClass>
        <micronaut.runtime>netty</micronaut.runtime>
    </properties>

    <repositories>
        <repository>
            <id>central</id>
            <url>https://repo.maven.apache.org/maven2</url>
        </repository>
    </repositories>

    <dependencies>
        <dependency>
            <groupId>io.micronaut</groupId>
            <artifactId>micronaut-inject</artifactId>
            <scope>compile</scope>
        </dependency>
        <dependency>
            <groupId>io.micronaut</groupId>
            <artifactId>micronaut-validation</artifactId>
            <scope>compile</scope>
        </dependency>
        <dependency>
            <groupId>io.micronaut</groupId>
            <artifactId>micronaut-http-server-netty</artifactId>
            <scope>compile</scope>
        </dependency>
        <dependency>
            <groupId>io.micronaut</groupId>
            <artifactId>micronaut-http-client</artifactId>
            <scope>compile</scope>
        </dependency>
        <dependency>
            <groupId>io.micronaut</groupId>
            <artifactId>micronaut-runtime</artifactId>
            <scope>compile</scope>
        </dependency>
        <dependency>
            <groupId>javax.annotation</groupId>
            <artifactId>javax.annotation-api</artifactId>
            <scope>compile</scope>
        </dependency>
        <dependency>
            <groupId>io.micronaut.mongodb</groupId>
            <artifactId>micronaut-mongo-sync</artifactId>
            <scope>compile</scope>
        </dependency>
        <dependency>
            <groupId>ch.qos.logback</groupId>
            <artifactId>logback-classic</artifactId>
            <scope>runtime</scope>
        </dependency>
        <dependency>
            <groupId>org.junit.jupiter</groupId>
            <artifactId>junit-jupiter-api</artifactId>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>org.junit.jupiter</groupId>
            <artifactId>junit-jupiter-engine</artifactId>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>io.micronaut.test</groupId>
            <artifactId>micronaut-test-junit5</artifactId>
            <scope>test</scope>
        </dependency>
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>io.micronaut.build</groupId>
                <artifactId>micronaut-maven-plugin</artifactId>
            </plugin>

            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-compiler-plugin</artifactId>
                <configuration>
                <annotationProcessorPaths>
                        <path>
                            <groupId>io.micronaut</groupId>
                   <artifactId>micronaut-inject-java</artifactId>
                            <version>${micronaut.version}</version>
                        </path>
                        <path>
                            <groupId>io.micronaut</groupId>
                     <artifactId>micronaut-validation</artifactId>
                            <version>${micronaut.version}</version>
                        </path>
                    </annotationProcessorPaths>
                    <compilerArgs>
          <arg>-Amicronaut.processing.group=com.knf.dev.demo</arg>
    <arg>-Amicronaut.processing.module=micronaut-mongodb-crud</arg>
                    </compilerArgs>
                </configuration>
            </plugin>
        </plugins>
    </build>
</project>


application.yaml

micronaut:
   application:
      name: micronautMongodbCrud
mongodb.uri: mongodb://localhost:27017

micronaut:
  server:   
    cors:
      enabled: true
      configurations:
        web:
          allowedOrigins:
            - http://localhost:3000


Create Document - User.java

package com.knf.dev.demo.entity;

import io.micronaut.core.annotation.Introspected;

@Introspected
public class User {
    
    private String id;
    private String firstName;
    private String lastName;
    private String emailId;

    public String getId() {
        return id;
    }

    public void setId(String id) {
        this.id = id;
    }

    public String getFirstName() {
        return firstName;
    }

    public void setFirstName(String firstName) {
        this.firstName = firstName;
    }

    public String getLastName() {
        return lastName;
    }

    public void setLastName(String lastName) {
        this.lastName = lastName;
    }

    public String getEmailId() {
        return emailId;
    }

    public void setEmailId(String emailId) {
        this.emailId = emailId;
    }

    public User(String id, String firstName, 
              String lastName, String emailId) {
        super();
        this.id = id;
        this.firstName = firstName;
        this.lastName = lastName;
        this.emailId = emailId;
    }

    public User() {
        super();
    }
}



Create UserRepository.java

package com.knf.dev.demo.repository.impl;

import java.util.ArrayList;
import java.util.List;
import java.util.Optional;
import org.bson.Document;
import org.bson.conversions.Bson;
import org.bson.types.ObjectId;
import com.knf.dev.demo.entity.User;
import com.mongodb.client.MongoClient;
import com.mongodb.client.MongoCollection;
import com.mongodb.client.MongoCursor;
import com.mongodb.client.model.Filters;
import jakarta.inject.Singleton;

@Singleton
public class UserRepository {
    private final MongoClient mongoClient;

    public UserRepository(MongoClient mongoClient) {
        this.mongoClient = mongoClient;
    }

    private MongoCollection<Document> getCollection() {

        return mongoClient.getDatabase("user-test").
                       getCollection("user-test");
    }

    public User saveUser(User user) {
        Document document = new Document().
        append("firstName", user.getFirstName())
                .append("lastName", user.getLastName()).
                append("emailId", user.getEmailId());
        getCollection().insertOne(document);
        user.setId(document.getObjectId("_id").toString());
        return user;
    }

    public User updateUser(String id, User user) {
        Optional<Document> optionalDocument = findDocumentById(id);
        if (optionalDocument.isPresent()) {
            Document document = optionalDocument.get();
            document.put("firstName", user.getFirstName());
            document.put("lastName", user.getLastName());
            document.put("emailId", user.getEmailId());
            Bson bsonFilter = Filters.eq("_id", new ObjectId(id));
            getCollection().replaceOne(bsonFilter, document);
        }
        return user;
    }

    public List<User> findAll() {
        List<User> users = new ArrayList<>();
        MongoCursor<Document> cursor = getCollection().
                          find().iterator();

        try {
            while (cursor.hasNext()) {
                Document document = cursor.next();
                User user = new User();
                user.setLastName(document.getString("lastName"));
                user.setFirstName(document.getString("firstName"));
                user.setEmailId(document.getString("emailId"));
                user.setId(String.
                     valueOf(document.getObjectId("_id")));
                users.add(user);
            }
        } finally {
            cursor.close();
        }
        return users;
    }

    public Optional<User> findUserById(String id) {
        return findDocumentById(id).map(this::mapUser);
    }

    public void deleteUserById(String id) {
        Bson bsonFilter = Filters.eq("_id", new ObjectId(id));
        getCollection().deleteOne(bsonFilter);
    }

    private Optional<Document> findDocumentById(String id) {
        Bson bsonFilter = Filters.eq("_id", new ObjectId(id));
        try (MongoCursor<Document> iterator = getCollection().
        find(bsonFilter).iterator()) {
            return iterator.hasNext() ? Optional.
            of(iterator.next()) : Optional.empty();
        }
    }

    private User mapUser(Document document) {
        User user = new User();
        user.setId(document.getObjectId("_id").toString());
        user.setEmailId(document.getString("emailId"));
        user.setLastName(document.getString("lastName"));
        user.setFirstName(document.getString("firstName"));
        return user;
    }
}


Create UserController.java

package com.knf.dev.demo.contoller;

import java.util.List;
import java.util.Optional;
import com.knf.dev.demo.entity.User;
import com.knf.dev.demo.repository.impl.UserRepository;
import io.micronaut.http.HttpResponse;
import io.micronaut.http.annotation.Body;
import io.micronaut.http.annotation.Controller;
import io.micronaut.http.annotation.Delete;
import io.micronaut.http.annotation.Get;
import io.micronaut.http.annotation.Post;
import io.micronaut.http.annotation.Put;
import jakarta.inject.Inject;

@Controller("/api/v1/users")
public class UserController {

    @Inject
    UserRepository userRepository;

    @Get
    public List<User> getUsers() {
        return userRepository.findAll();
    }

    @Get("/{id}")
    public Optional<User> getUser(String id) {
        return userRepository.findUserById(id);
    }

    @Post
    public HttpResponse<User> addUser(@Body User user) {
        userRepository.saveUser(user);
        return HttpResponse.created(user);
    }

    @Put("/{id}")
    public HttpResponse<User> updateUser(String id, 
           @Body User user) {

        userRepository.updateUser(id, user);
        return HttpResponse.created(user);
    }

    @Delete("/{id}")
    public HttpResponse<Void> delete(String id) {
        userRepository.deleteUserById(id);
        return HttpResponse.noContent();
    }
}


Create Main Class

package com.knf.dev.demo;

import io.micronaut.runtime.Micronaut;

public class Application {

    public static void main(String[] args) {
        Micronaut.run(Application.class, args);
    }
}


Run the backend application

mvn mn:run or run as java application


PART 2 - UI Development using React.js

Package structure - Front end



package.json

{
    "name": "react-frontend",
    "version": "0.1.0",
    "private": true,
    "dependencies": {
        "@testing-library/jest-dom": "^4.2.4",
        "@testing-library/react": "^9.5.0",
        "@testing-library/user-event": "^7.2.1",
        "axios": "^0.19.2",
        "bootstrap": "^4.5.0",
        "react": "^16.13.1",
        "react-dom": "^16.13.1",
        "react-router-dom": "^5.2.0",
        "react-scripts": "3.4.1"
    },
    "scripts": {
        "start": "react-scripts start",
        "build": "react-scripts build",
        "test": "react-scripts test",
        "eject": "react-scripts eject"
    },
    "eslintConfig": {
        "extends": "react-app"
    },
    "browserslist": {
        "production": [
            ">0.2%",
            "not dead",
            "not op_mini all"
        ],
        "development": [
            "last 1 chrome version",
            "last 1 firefox version",
            "last 1 safari version"
        ]
    }
}



CreateUserComponent.jsx

import React, { Component } from 'react'
import UserService from '../services/UserService';
class CreateUserComponent extends Component {
    constructor(props) {
        super(props)
        this.state = {
            // step 2
            id: this.props.match.params.id,
            firstName: '',
            lastName: '',
            emailId: ''
        }
        this.changeFirstNameHandler = this.
                         changeFirstNameHandler.bind(this);
        this.changeLastNameHandler = this.
                         changeLastNameHandler.bind(this);
        this.saveOrUpdateUser = this.saveOrUpdateUser.bind(this);
    }
    // step 3
    componentDidMount() {
        // step 4
        if (this.state.id === '_add') {
            return
        } else {
            UserService.getUserById(this.state.id).then((res) => {
                let user = res.data;
                this.setState({
                    firstName: user.firstName,
                    lastName: user.lastName,
                    emailId: user.emailId
                });
            });
        }
    }
    saveOrUpdateUser = (e) => {
        e.preventDefault();
        let user = {
            firstName: this.state.firstName, 
             lastName: this.state.lastName,
              emailId: this.state.emailId
        };
        console.log('user => ' + JSON.stringify(user));
        // step 5
        if (this.state.id === '_add') {
            UserService.createUser(user).then(res => {
                this.props.history.push('/users');
            });
        } else {
            UserService.updateUser(user, this.state.id).then(res => {
                this.props.history.push('/users');
            });
        }
    }
    changeFirstNameHandler = (event) => {
        this.setState({ firstName: event.target.value });
    }
    changeLastNameHandler = (event) => {
        this.setState({ lastName: event.target.value });
    }
    changeEmailHandler = (event) => {
        this.setState({ emailId: event.target.value });
    }
    cancel() {
        this.props.history.push('/users');
    }
    getTitle() {
        if (this.state.id === '_add') {
            return <h3 className="text-center">Add User</h3>
        } else {
            return <h3 className="text-center">Update User</h3>
        }
    }
    render() {
        return (
            <div>
                <br></br>
                <div className="container">
                    <div className="row">
          <div className="card col-md-6 offset-md-3 offset-md-3">
                            {
                                this.getTitle()
                            }
                            <div className="card-body">
                                <form>
                                    <div className="form-group">
                                       <label> First Name: </label>
   <input placeholder="First Name" name="firstName" 
        className="form-control"
         value={this.state.firstName} 
          onChange={this.changeFirstNameHandler} />
                                    </div>
                                    <div className="form-group">
                                        <label> Last Name: </label>
      <input placeholder="Last Name" name="lastName" 
        className="form-control"
          value={this.state.lastName} 
            onChange={this.changeLastNameHandler} />
                                    </div>
                                    <div className="form-group">
                                        <label> Email Id: </label>
   <input placeholder="Email Address" name="emailId" 
      className="form-control"
           value={this.state.emailId} 
               onChange={this.changeEmailHandler} />
                                    </div>
  <button className="btn btn-success" 
         onClick={this.saveOrUpdateUser}>
                                 Save</button>
   <button className="btn btn-danger" 
         onClick={this.cancel.bind(this)} 
            style={{ marginLeft: "10px" }}>Cancel</button>
                               </form>
                            </div>
                        </div>
                    </div>
                </div>
            </div>
        )
    }
}
export default CreateUserComponent



ListUserComponent.jsx

import React, { Component } from 'react'
import UserService from '../services/UserService'
class ListUserComponent extends Component {
    constructor(props) {
        super(props)
        this.state = {
            users: []
        }
        this.addUser = this.addUser.bind(this);
        this.editUser = this.editUser.bind(this);
        this.deleteUser = this.deleteUser.bind(this);
    }
    deleteUser(id) {
        UserService.deleteUser(id).then(res => {
            this.setState({
                users: this.state.users.filter(user =>
                    user.id !== id)
            });
        });
    }
    viewUser(id) {
        this.props.history.push(`/view-user/${id}`);
    }
    editUser(id) {
        this.props.history.push(`/add-user/${id}`);
    }
    componentDidMount() {
        UserService.getUsers().then((res) => {
            this.setState({ users: res.data });
        });
    }
    addUser() {
        this.props.history.push('/add-user/_add');
    }
    render() {
        return (
            <div>
                <h2 className="text-center">Users List</h2>
                <div className="row">
                    <button className="btn btn-primary" 
                       onClick={this.addUser}>
                         Add User</button>
                </div>
                <br></br>
                <div className="row">
            <table className="table table-striped table-bordered">
                        <thead>
                            <tr>
                                <th> User First Name</th>
                                <th> User Last Name</th>
                                <th> User Email Id</th>
                                <th> Actions</th>
                            </tr>
                        </thead>
                        <tbody>
                            {
                                this.state.users.map(
                                    user =>
                                        <tr key={user.id}>
                                        <td> {user.firstName} </td>
                                        <td> {user.lastName}</td>
                                        <td> {user.emailId}</td>
                                           <td>
        <button onClick={() => this.editUser(user.id)} 
          className="btn btn-info">Update </button>
        <button style={{ marginLeft: "10px" }} onClick=
          {() => this.deleteUser(user.id)} 
          className="btn btn-danger">Delete </button>
        <button style={{ marginLeft: "10px" }} onClick=
          {() => this.viewUser(user.id)} 
            className="btn btn-info">View </button>
                                            </td>
                                        </tr>
                                )
                            }
                        </tbody>
                    </table>
                </div>
            </div>
        )
    }
}
export default ListUserComponent


UpdateUserComponent.jsx

import React, { Component } from 'react'
import UserService from '../services/UserService';
class UpdateUserComponent extends Component {
    constructor(props) {
        super(props)
        this.state = {
            id: this.props.match.params.id,
            firstName: '',
            lastName: '',
            emailId: ''
        }
        this.changeFirstNameHandler = 
              this.changeFirstNameHandler.bind(this);
        this.changeLastNameHandler = 
              this.changeLastNameHandler.bind(this);
        this.updateUser = this.updateUser.bind(this);
    }
    componentDidMount() {
        UserService.getUserById(this.state.id).then((res) => {
            let user = res.data;
            this.setState({
                firstName: user.firstName,
                lastName: user.lastName,
                emailId: user.emailId
            });
        });
    }
    updateUser = (e) => {
        e.preventDefault();
        let user = {
            firstName: this.state.firstName, 
             lastName: this.state.lastName,
              emailId: this.state.emailId
        };
        console.log('user => ' + JSON.stringify(user));
        console.log('id => ' + JSON.stringify(this.state.id));
        UserService.updateUser(user, this.state.id).then(res => {
            this.props.history.push('/users');
        });
    }
    changeFirstNameHandler = (event) => {
        this.setState({ firstName: event.target.value });
    }
    changeLastNameHandler = (event) => {
        this.setState({ lastName: event.target.value });
    }
    changeEmailHandler = (event) => {
        this.setState({ emailId: event.target.value });
    }
    cancel() {
        this.props.history.push('/users');
    }
    render() {
        return (
            <div>
                <br></br>
                <div className="container">
                    <div className="row">
           <div className="card col-md-6 offset-md-3 offset-md-3">
                      <h3 className="text-center">Update User</h3>
                            <div className="card-body">
                                <form>
                                    <div className="form-group">
                                       <label> First Name: </label>
     <input placeholder="First Name" name="firstName" 
         className="form-control"
           value={this.state.firstName} 
             onChange={this.changeFirstNameHandler} />
                                    </div>
                                    <div className="form-group">
                                        <label> Last Name: </label>
     <input placeholder="Last Name" name="lastName" 
         className="form-control"
           value={this.state.lastName} 
             onChange={this.changeLastNameHandler} />
                                    </div>
                                    <div className="form-group">
                                        <label> Email Id: </label>
     <input placeholder="Email Address" name="emailId"
          className="form-control"
             value={this.state.emailId} 
               onChange={this.changeEmailHandler} />
                                    </div>
     <button className="btn btn-success" 
           onClick={this.updateUser}>Save</button>
     <button className="btn btn-danger" 
           onClick={this.cancel.bind(this)} style=
                 {{ marginLeft: "10px" }}>Cancel</button>
                                </form>
                            </div>
                        </div>
                    </div>
                </div>
            </div>
        )
    }
}
export default UpdateUserComponent


ViewUserComponent.jsx

import React, { Component } from 'react'
import UserService from '../services/UserService'
class ViewUserComponent extends Component {
    constructor(props) {
        super(props)
        this.state = {
            id: this.props.match.params.id,
            user: {}
        }
    }
    componentDidMount() {
        UserService.getUserById(this.state.id).then(res => {
            this.setState({ user: res.data });
        })
    }
    render() {
        return (
            <div>
                <br></br>
                <div className="card col-md-6 offset-md-3">
               <h3 className="text-center"> View User Details</h3>
                    <div className="card-body">
                        <div className="row">
                            <label> User First Name: </label>
                            <div> {this.state.user.firstName}</div>
                        </div>
                        <div className="row">
                            <label> User Last Name: </label>
                            <div> {this.state.user.lastName}</div>
                        </div>
                        <div className="row">
                            <label> User Email ID: </label>
                            <div> {this.state.user.emailId}</div>
                        </div>
                    </div>
                </div>
            </div>
        )
    }
}
export default ViewUserComponent


UserService.js

import axios from 'axios';

const USER_API_BASE_URL = "http://localhost:8080/api/v1/users";
class UserService {
    getUsers() {
        return axios.get(USER_API_BASE_URL);
    }
    createUser(user) {
        return axios.post(USER_API_BASE_URL, user);
    }
    getUserById(userId) {
        return axios.get(USER_API_BASE_URL + '/' + userId);
    }
    updateUser(user, userId) {
        return axios.put(USER_API_BASE_URL + '/' + userId, user);
    }
    deleteUser(userId) {
        return axios.delete(USER_API_BASE_URL + '/' + userId);
    }
}
export default new UserService()

App.js

import React from 'react';
import logo from './logo.svg';
import './App.css';
import {BrowserRouter as Router, Route, Switch} from 'react-router-dom'
import ListUserComponent from './components/ListUserComponent';
import HeaderComponent from './components/HeaderComponent';
import FooterComponent from './components/FooterComponent';
import CreateUserComponent from './components/CreateUserComponent';
import ViewUserComponent from './components/ViewUserComponent';

function App() {
  return (
    <div>
        <Router>
              <HeaderComponent />
                <div className="container">

                    <Switch> 

  <Route path = "/" exact component = {ListUserComponent}></Route>
  <Route path = "/users" component = {ListUserComponent}></Route>
  <Route path = "/add-user/:id" 
            component = {CreateUserComponent}></Route>
  <Route path = "/view-user/:id" 
          component = {ViewUserComponent}></Route>
                     
                    </Switch>
                </div>
              <FooterComponent />
        </Router>
    </div>
    
  );
}

export default App;

Download Source code - Local environment setup

Step1: Install JDK 17 - click here


Step2: Install eclipse - click here


Step3: Install ReactJS - click here


Step4: Install VS code - click here


Step5: Download/clone source code - click here


Step6: Install Apache Maven - click here


Step7: Install MongoDB - click here



Backend setup


Step8: Execute the command - mvn clean install


Step9: Run the app as a Java application or execute  mvn mn:run



Frontend setup


Step10: The npm install installs all modules that are listed on package.json file and their dependencies - npm install


Step11: Run the Frontend application - npm start

Popular posts from this blog

Learn Java 8 streams with an example - print odd/even numbers from Array and List

Example 1: Java 8 program to print odd numbers from a List   import java.util.Arrays; import java.util.List; import java.util.stream.Collectors; /*Java 8 Program to find Odd Numbers from a List*/ public class DriverClass { public static void main( String [] args) { List < Integer > numbers = Arrays. asList( 1 , 4 , 8 , 40 , 11 , 22 , 33 , 99 ); List < Integer > oddNumbers = numbers.stream(). filter(o -> o % 2 != 0 ). collect(Collectors.toList()); System.out.println(oddNumbers); } } 1. Initialize List using Arrays.asList() method. Java's built-in Arrays.asList() method converts an array into a list. This method takes an array as an argument and returns a List object. 2.  Java List interface provides stream() method which returns a sequential Stream with list of Integer as its source. 3. The Java stream filter(...
Read more

Java Stream API - How to convert List of objects to another List of objects using Java streams?

Image
In this section, we will show you how to convert a List of objects to another List of objects in Java using the Java streams map(). The ‘map’ method maps each element to its corresponding result. Java Stream API   The Java Stream API provides a functional programming approach over the object oriented capabilities of Java. It is used for processing collections of objects. The Stream in Java can be defined as a sequence of elements from a source List, Set or Array. Most of the stream operations return a Stream. This avails engender a chain of stream operations(stream pipe-lining). The streams withal support the aggregate or terminal operations on the elements. for example, finding the sum or maximum element or finding the average etc...Stream operations can either be executed sequentially or parallel. when performed parallelly, it is called a parallel stream.   Stream map() Method   The Java 8 Stream map() is an intermediate operation. It converts Stream<obj1> to Str...
Read more

Registration and Login with Spring Boot + Spring Security + Thymeleaf

Image
In this section, we will learn how to create user registration and login using Spring boot, Spring security, Thymeleaf, JPA, and H2DB. The GitHub repository link is provided at the end of this tutorial. You can download the source code. Technologies used: Spring Boot 2.5.5  Spring Data JPA  Spring Security  Thymeleaf  Maven 3+  Java 17  H2 Database   User Interface User Registration Authentication Failed Authentication success Sign out Final Project Structure: Complete 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-pare...
Read more

Java, Spring Boot Mini Project - Library Management System - Download

Image
Hello everyone, Hope you are doing well. Here, we provide a Library Management System mini-project for beginners, it's free for download. Maybe you can build more on top of this project and create your own product, that's all about you. The source code download link is provided at the end of this post. 1. Benefit of this project You could cover the following technologies and features by learning and debugging this mini project. Java 17 Java Stream Java Lamda Expressions Java Records Functional programming Object-oriented programming var Keyword in Java Generics in Java Java Switch Spring boot 2.6.4 Spring Security Thymeleaf template engine OpenCSV Spring Data JPA Server Side Pagination H2 Database  Bootstrap HTML CSS and more... 2. Objective Of Spring Boot On Library Management System The main objective of this project is to manage the details of the books, author, category, and publisher. Only Admin/Librarian will manage all these activities. Also, they can export the data in ...
Read more

ReactJS, Spring Boot JWT Authentication Example

Image
In this tutorial, we’ll create a user registration & login example using ReactJS, Spring Boot, Spring Security, and JWT authentication. You could download the source code from our Github repository, the download link is provided at the end of this tutorial. Technologies used Backend Technologies: Java 17 Spring Boot 2.7.0 Spring Security Spring Data JPA JWT H2 Database Frontend Technologies: React 17.0.1 Axios 0.27.2 Redux 4.0.5 Bootstrap 4.5.2 ReactJS - SpringBoot - JWT - Flow Backend Project Directory: Frontend Project Directory: Following is the screenshot of our application - User Registration: User Signin: Profile View: Access Resource: We will build two projects:  1. Backend:   spring-boot-security-jwt 2. Frontend: react-redux-jwt Project 1: spring-boot-security-jwt 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"...
Read more

Top 5 Java ORM tools - 2024

Image
  The term ORM refers to object-relational mapping, which uses objects to adapt programming languages to database systems while allowing them to function with SQL and object-oriented programming ideas. Any kind of database management system that can accomplish object mapping to the table in the virtual system is suitable for the implementation of ORM. Java has a wide variety of ORM tools, some of which are mentioned below: 1. Hibernate Hibernate is a lightweight, open-source, non-invasive Java ORM (Object-Relational Mapping) framework that allows developers to create objects that function independently of database software and create persistence logic in any Java or JavaEE application. It offers an abstraction layer, so developers don't have to bother about implementations; Hibernate handles these tasks internally, such as connecting to databases and creating queries to carry out CRUD operations, among other things. Persistence logic development is done with it. Persistence logic r...
Read more

Java - Blowfish Encryption and decryption Example

Image
Blowfish is an encryption method developed by Bruce Schneier in 1993 as an alternative to the DES encryption method. It is significantly faster than DES and provides good encryption speed, although no effective cryptanalysis technique has been found to date. It is one of the first secure block ciphers that is not protected by any patents and is therefore freely available for anyone to use. This is a symmetric block cipher algorithm. Block size: 64 bits Key size: variable size from 32 to 448 bits number of subsections: 18 [P-array] number of rounds: 16 number of substitution blocks: 4 [each with 512 records of 32 bits each] develop  Example 1: Encryption and decryption using Blowfish import java.io.UnsupportedEncodingException; import java.nio.charset.Charset; import java.security.InvalidKeyException; import java.security.NoSuchAlgorithmException; import java.util.Base64; import javax.crypto.BadPaddingException; import javax.crypto.Cipher; import javax.crypto.IllegalBlockSiz...
Read more

Spring boot video streaming example-HTML5

Image
Hello everyone, Today we will learn how to stream MP4 video using Spring Boot and Spring Web Flux.  The Source code download link is provided at the end of this post. New, Quarkus Practice User Interface   Project Structure: G radle(build.gradle) plugins { id 'org.springframework.boot' version '2.5.4' id 'io.spring.dependency-management' version '1.0.11.RELEASE' id 'java' } group = 'com.knf.demo' version = '0.0.1-SNAPSHOT' sourceCompatibility = '11' repositories { mavenCentral() } dependencies { implementation 'org.springframework.boot:spring-boot-starter-webflux' testImplementation 'org.springframework.boot:spring-boot-starter-test' testImplementation 'io.projectreactor:reactor-test' } test { useJUnitPlatform() } Service (VideoStreamingService.java) package  com.knf.demo.service ; import org.springframework.beans.factory.annotation. Autowired ; import org.springframework...
Read more

Google Cloud Storage + Spring Boot - File Upload, Download, and Delete

Image
In this section, we will learn  how to  create a simple spring boot application to perform different file operations such as upload, download, list, and delete files from the Google Cloud Storage. 1.  A little bit of Background Google Cloud Storage Cloud Storage is a managed service for storing unstructured data. Store any amount of data and retrieve it as often as you like. More Info - click here! Spring Boot Spring Boot makes it easy to create stand-alone, production-grade Spring-based Applications that you can "just run".  More Info - click here! 2. Create a GCP Project First, Sign into the Google console at  https://console.cloud.google.com . You can create a new project by first selecting the project dropdown in the top left and selecting " New Project ". Next, specify your GCP  Project name  and  Project ID . Then  Click on the " CREATE " button. Copy " Project ID " and keep it for future purposes. 3. Create a Google Cloud Storage bucke...
Read more