Step26.md

What we will do:

• Basic Spring Rest Services.
• We use com.fasterxml.jackson.core:jackson-databind
• http://localhost:8080/rest/todos
• How does the magic happen?

Useful Snippets

@RestController
public class TodoRestController {
    @Autowired
    private TodoService service;

    @RequestMapping(value = "/rest/todos", method = RequestMethod.GET)
    public List<Todo> listAllTodos() {
        List<Todo> users = service.retrieveTodos("in28Minutes");
        return users;
    }

}	

Files List

/pom.xml

<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.in28minutes.springboot.web</groupId>
    <artifactId>Spring-Boot-First-Web-Application</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <packaging>jar</packaging>

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>1.4.0.RELEASE</version>
    </parent>

    <dependencies>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-security</artifactId>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-tomcat</artifactId>
            <scope>provided</scope>
        </dependency>

        <dependency>
            <groupId>org.apache.tomcat.embed</groupId>
            <artifactId>tomcat-embed-jasper</artifactId>
            <scope>provided</scope>
        </dependency>

        <dependency>
            <groupId>javax.servlet</groupId>
            <artifactId>jstl</artifactId>
        </dependency>

        <dependency>
            <groupId>org.webjars</groupId>
            <artifactId>bootstrap</artifactId>
            <version>3.3.6</version>
        </dependency>

        <dependency>
            <groupId>org.webjars</groupId>
            <artifactId>jquery</artifactId>
            <version>1.9.1</version>
        </dependency>

        <dependency>
            <groupId>org.webjars</groupId>
            <artifactId>bootstrap-datepicker</artifactId>
            <version>1.0.1</version>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-devtools</artifactId>
            <optional>true</optional>
        </dependency>


    </dependencies>

    <properties>
        <java.version>1.8</java.version>
    </properties>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>

</project>

/src/main/java/com/in28minutes/springboot/web/controller/ExceptionController.java

package com.in28minutes.springboot.web.controller;

import javax.servlet.http.HttpServletRequest;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.ExceptionHandler;
import org.springframework.web.servlet.ModelAndView;

@Controller("error")
public class ExceptionController {

    private Log logger = LogFactory.getLog(ExceptionController.class);

    @ExceptionHandler(Exception.class)
    public ModelAndView handleError(HttpServletRequest req, Exception ex) {
        logger.error("Request: " + req.getRequestURL() + " raised " + ex);

        ModelAndView mav = new ModelAndView();
        mav.addObject("exception", ex);
        mav.addObject("url", req.getRequestURL());
        mav.setViewName("error");
        return mav;
    }
}

/src/main/java/com/in28minutes/springboot/web/controller/LogoutController.java

package com.in28minutes.springboot.web.controller;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.springframework.security.core.Authentication;
import org.springframework.security.core.context.SecurityContextHolder;
import org.springframework.security.web.authentication.logout.SecurityContextLogoutHandler;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;

@Controller
public class LogoutController {

    @RequestMapping(value = "/logout", method = RequestMethod.GET)
    public String logout(HttpServletRequest request,
            HttpServletResponse response) {
        Authentication auth = SecurityContextHolder.getContext()
                .getAuthentication();
        if (auth != null) {
            new SecurityContextLogoutHandler().logout(request, response, auth);
        }
        return "redirect:/";
    }
}

/src/main/java/com/in28minutes/springboot/web/controller/TodoController.java

package com.in28minutes.springboot.web.controller;

import java.text.SimpleDateFormat;
import java.util.Date;

import javax.validation.Valid;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.propertyeditors.CustomDateEditor;
import org.springframework.security.core.context.SecurityContextHolder;
import org.springframework.security.core.userdetails.UserDetails;
import org.springframework.stereotype.Controller;
import org.springframework.ui.ModelMap;
import org.springframework.validation.BindingResult;
import org.springframework.web.bind.WebDataBinder;
import org.springframework.web.bind.annotation.InitBinder;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RequestParam;

import com.in28minutes.springboot.web.model.Todo;
import com.in28minutes.springboot.web.service.TodoService;

@Controller
public class TodoController {

    @Autowired
    private TodoService service;

    @InitBinder
    protected void initBinder(WebDataBinder binder) {
        SimpleDateFormat dateFormat = new SimpleDateFormat("dd/MM/yyyy");
        binder.registerCustomEditor(Date.class, new CustomDateEditor(
                dateFormat, false));
    }

    @RequestMapping(value = "/list-todos", method = RequestMethod.GET)
    public String showTodosList(ModelMap model) {
        String user = getLoggedInUserName();
        model.addAttribute("todos", service.retrieveTodos(user));
        return "list-todos";
    }

    @RequestMapping(value = "/add-todo", method = RequestMethod.GET)
    public String showAddTodoPage(ModelMap model) {
        model.addAttribute("todo", new Todo());
        return "todo";
    }

    @RequestMapping(value = "/add-todo", method = RequestMethod.POST)
    public String addTodo(ModelMap model, @Valid Todo todo, BindingResult result) {

        if (result.hasErrors()) {
            return "todo";
        }

        service.addTodo(getLoggedInUserName(), todo.getDesc(),
                todo.getTargetDate(), false);
        model.clear();// to prevent request parameter "name" to be passed
        return "redirect:/list-todos";
    }

    private String getLoggedInUserName() {
        Object principal = SecurityContextHolder.getContext()
                .getAuthentication().getPrincipal();

        if (principal instanceof UserDetails) {
            return ((UserDetails) principal).getUsername();
        }

        return principal.toString();
    }

    @RequestMapping(value = "/update-todo", method = RequestMethod.GET)
    public String showUpdateTodoPage(ModelMap model, @RequestParam int id) {
        model.addAttribute("todo", service.retrieveTodo(id));
        return "todo";
    }

    @RequestMapping(value = "/update-todo", method = RequestMethod.POST)
    public String updateTodo(ModelMap model, @Valid Todo todo,
            BindingResult result) {
        if (result.hasErrors()) {
            return "todo";
        }

        todo.setUser(getLoggedInUserName());
        service.updateTodo(todo);

        model.clear();// to prevent request parameter "name" to be passed
        return "redirect:/list-todos";
    }

    @RequestMapping(value = "/delete-todo", method = RequestMethod.GET)
    public String deleteTodo(@RequestParam int id) {
        service.deleteTodo(id);

        return "redirect:/list-todos";
    }

}

/src/main/java/com/in28minutes/springboot/web/controller/TodoRestController.java

package com.in28minutes.springboot.web.controller;

import java.util.List;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RestController;

import com.in28minutes.springboot.web.model.Todo;
import com.in28minutes.springboot.web.service.TodoService;

@RestController
public class TodoRestController {
    @Autowired
    private TodoService service;

    @RequestMapping(value = "/rest/todos", method = RequestMethod.GET)
    public List<Todo> listAllTodos() {
        List<Todo> users = service.retrieveTodos("in28Minutes");
        return users;
    }

}

/src/main/java/com/in28minutes/springboot/web/controller/WelcomeController.java

package com.in28minutes.springboot.web.controller;

import org.springframework.security.core.context.SecurityContextHolder;
import org.springframework.security.core.userdetails.UserDetails;
import org.springframework.stereotype.Controller;
import org.springframework.ui.ModelMap;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;

@Controller
public class WelcomeController {

    @RequestMapping(value = "/", method = RequestMethod.GET)
    public String showWelcomePage(ModelMap model) {
        model.put("name", getLoggedInUserName());
        return "welcome";
    }

    private String getLoggedInUserName() {
        Object principal = SecurityContextHolder.getContext()
                .getAuthentication().getPrincipal();

        if (principal instanceof UserDetails) {
            return ((UserDetails) principal).getUsername();
        }

        return principal.toString();
    }

}

/src/main/java/com/in28minutes/springboot/web/model/Todo.java

package com.in28minutes.springboot.web.model;

import java.util.Date;

import javax.validation.constraints.Size;

public class Todo {

    private int id;

    private String user;

    @Size(min = 10, message = "Enter atleast 10 Characters.")
    private String desc;

    private Date targetDate;

    private boolean isDone;

    public Todo() {
        super();
    }

    public Todo(int id, String user, String desc, Date targetDate,
            boolean isDone) {
        super();
        this.id = id;
        this.user = user;
        this.desc = desc;
        this.targetDate = targetDate;
        this.isDone = isDone;
    }

    public int getId() {
        return id;
    }

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

    public String getUser() {
        return user;
    }

    public void setUser(String user) {
        this.user = user;
    }

    public String getDesc() {
        return desc;
    }

    public void setDesc(String desc) {
        this.desc = desc;
    }

    public Date getTargetDate() {
        return targetDate;
    }

    public void setTargetDate(Date targetDate) {
        this.targetDate = targetDate;
    }

    public boolean isDone() {
        return isDone;
    }

    public void setDone(boolean isDone) {
        this.isDone = isDone;
    }

    @Override
    public int hashCode() {
        final int prime = 31;
        int result = 1;
        result = prime * result + id;
        return result;
    }

    @Override
    public boolean equals(Object obj) {
        if (this == obj) {
            return true;
        }
        if (obj == null) {
            return false;
        }
        if (getClass() != obj.getClass()) {
            return false;
        }
        Todo other = (Todo) obj;
        if (id != other.id) {
            return false;
        }
        return true;
    }

    @Override
    public String toString() {
        return String.format(
                "Todo [id=%s, user=%s, desc=%s, targetDate=%s, isDone=%s]", id,
                user, desc, targetDate, isDone);
    }

}

/src/main/java/com/in28minutes/springboot/web/security/SecurityConfiguration.java

package com.in28minutes.springboot.web.security;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.Configuration;
import org.springframework.security.config.annotation.authentication.builders.AuthenticationManagerBuilder;
import org.springframework.security.config.annotation.web.builders.HttpSecurity;
import org.springframework.security.config.annotation.web.configuration.EnableWebSecurity;
import org.springframework.security.config.annotation.web.configuration.WebSecurityConfigurerAdapter;

@Configuration
@EnableWebSecurity
public class SecurityConfiguration extends WebSecurityConfigurerAdapter {

    @Autowired
    public void configureGlobalSecurity(AuthenticationManagerBuilder auth)
            throws Exception {
        auth.inMemoryAuthentication().withUser("in28Minutes").password("dummy")
        .roles("USER", "ADMIN");
    }

    @Override
    protected void configure(HttpSecurity http) throws Exception {
        http.authorizeRequests().antMatchers("/login").permitAll()
        .antMatchers("/", "/*todo*/**").access("hasRole('USER')").and()
        .formLogin();
    }
}

/src/main/java/com/in28minutes/springboot/web/service/LoginService.java

package com.in28minutes.springboot.web.service;

import org.springframework.stereotype.Component;

@Component
public class LoginService {
    public boolean validateUser(String user, String password) {
        return user.equalsIgnoreCase("in28Minutes") && password.equals("dummy");
    }
}

/src/main/java/com/in28minutes/springboot/web/service/TodoService.java

package com.in28minutes.springboot.web.service;

import java.util.ArrayList;
import java.util.Date;
import java.util.Iterator;
import java.util.List;

import org.springframework.stereotype.Service;

import com.in28minutes.springboot.web.model.Todo;

@Service
public class TodoService {
    private static List<Todo> todos = new ArrayList<Todo>();
    private static int todoCount = 3;

    static {
        todos.add(new Todo(1, "in28Minutes", "Learn Spring MVC", new Date(),
                false));
        todos.add(new Todo(2, "in28Minutes", "Learn Struts", new Date(), false));
        todos.add(new Todo(3, "in28Minutes", "Learn Hibernate", new Date(),
                false));
    }

    public List<Todo> retrieveTodos(String user) {
        List<Todo> filteredTodos = new ArrayList<Todo>();
        for (Todo todo : todos) {
            if (todo.getUser().equalsIgnoreCase(user)) {
                filteredTodos.add(todo);
            }
        }
        return filteredTodos;
    }

    public Todo retrieveTodo(int id) {
        for (Todo todo : todos) {
            if (todo.getId() == id) {
                return todo;
            }
        }
        return null;
    }

    public void updateTodo(Todo todo) {
        todos.remove(todo);
        todos.add(todo);
    }

    public void addTodo(String name, String desc, Date targetDate,
            boolean isDone) {
        todos.add(new Todo(++todoCount, name, desc, targetDate, isDone));
    }

    public void deleteTodo(int id) {
        Iterator<Todo> iterator = todos.iterator();
        while (iterator.hasNext()) {
            Todo todo = iterator.next();
            if (todo.getId() == id) {
                iterator.remove();
            }
        }
    }
}

/src/main/java/com/in28minutes/springboot/web/WebApplication.java

package com.in28minutes.springboot.web;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.ApplicationContext;

@SpringBootApplication
public class WebApplication {

    public static void main(String[] args) {
        ApplicationContext ctx = SpringApplication.run(WebApplication.class, args);
    }
}

/src/main/resources/application.properties

spring.mvc.view.prefix: /WEB-INF/jsp/
spring.mvc.view.suffix: .jsp
logging.level.: DEBUG

/src/main/webapp/WEB-INF/jsp/common/footer.jspf

<script src="webjars/jquery/1.9.1/jquery.min.js"></script>
<script src="webjars/bootstrap/3.3.6/js/bootstrap.min.js"></script>
<script
    src="webjars/bootstrap-datepicker/1.0.1/js/bootstrap-datepicker.js"></script>

</body>
</html>

/src/main/webapp/WEB-INF/jsp/common/header.jspf

<%@taglib uri="http://www.springframework.org/tags/form" prefix="form"%>
<%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%>
<%@ taglib uri="http://java.sun.com/jsp/jstl/fmt" prefix="fmt"%>
<html>
<head>
<title>Todos Application</title>
<link href="webjars/bootstrap/3.3.6/css/bootstrap.min.css"
    rel="stylesheet">
</head>

<body>

/src/main/webapp/WEB-INF/jsp/common/navigation.jspf

<nav role="navigation" class="navbar navbar-default">

    <div class="">
        <a href="http://www.in28minutes.com" class="navbar-brand">in28Minutes</a>
    </div>

    <div class="navbar-collapse">
        <ul class="nav navbar-nav">
            <li class="active"><a href="/">Home</a></li>
            <li><a href="/list-todos">Todos</a></li>
        </ul>
        <ul class="nav navbar-nav navbar-right">
            <li><a href="/logout">Logout</a></li>
        </ul>
    </div>

</nav>

/src/main/webapp/WEB-INF/jsp/error.jsp

<%@ include file="common/header.jspf"%>
<%@ include file="common/navigation.jspf"%>
<div class="container">
    Application has encountered an error. Please contact support on ...
</div>

<%@ include file="common/footer.jspf"%>

/src/main/webapp/WEB-INF/jsp/list-todos.jsp

<%@ include file="common/header.jspf"%>
<%@ include file="common/navigation.jspf"%>

<div class="container">
    <table class="table table-striped">
        <caption>Your Todos are</caption>
        <thead>
            <tr>
                <th>Description</th>
                <th>Date</th>
                <th>Completed</th>
                <th></th>
            </tr>
        </thead>
        <tbody>
            <c:forEach items="${todos}" var="todo">
                <tr>
                    <td>${todo.desc}</td>
                    <td><fmt:formatDate pattern="dd/MM/yyyy"
                            value="${todo.targetDate}" /></td>
                    <td>${todo.done}</td>
                    <td><a type="button" class="btn btn-primary"
                        href="/update-todo?id=${todo.id}">Edit</a> <a type="button"
                        class="btn btn-warning" href="/delete-todo?id=${todo.id}">Delete</a>
                    </td>
                </tr>
            </c:forEach>
        </tbody>
    </table>
    <div>
        <a type="button" class="btn btn-success" href="/add-todo">Add</a>
    </div>
</div>
<%@ include file="common/footer.jspf"%>

/src/main/webapp/WEB-INF/jsp/login.jsp

<%@ include file="common/header.jspf"%>
<%@ include file="common/navigation.jspf"%>
<div class="container">
    <p>
        <font color="red">${errorMessage}</font>
    </p>
    <form action="/login" method="POST">
        <fieldset class="form-group">
            <label>Name</label> <input name="name" type="text"
                class="form-control" />
        </fieldset>
        <fieldset class="form-group">
            <label>Password</label> <input name="password" type="password"
                class="form-control" />
        </fieldset>
        <button type="submit" class="btn btn-success">Submit</button>
    </form>

</div>

<%@ include file="common/footer.jspf"%>

/src/main/webapp/WEB-INF/jsp/todo.jsp

<%@ include file="common/header.jspf"%>
<%@ include file="common/navigation.jspf"%>
<div class="container">
    <form:form method="post" commandName="todo">
        <form:hidden path="id" />
        <fieldset class="form-group">
            <form:label path="desc">Description</form:label>
            <form:input path="desc" type="text" class="form-control"
                required="required" />
            <form:errors path="desc" cssClass="text-warning" />
        </fieldset>
        <fieldset class="form-group">
            <form:label path="targetDate">Target Date</form:label>
            <form:input path="targetDate" type="text" class="form-control"
                required="required" />
            <form:errors path="targetDate" cssClass="text-warning" />
        </fieldset>
        <button type="submit" class="btn btn-success">Submit</button>
    </form:form>
</div>

<%@ include file="common/footer.jspf"%>

<script>
    $('#targetDate').datepicker({
        format : 'dd/mm/yyyy'
    });
</script>

/src/main/webapp/WEB-INF/jsp/welcome.jsp

<%@ include file="common/header.jspf"%>
<%@ include file="common/navigation.jspf"%>
<div class="container">
    Welcome ${name}. You are now authenticated.
</div>

<%@ include file="common/footer.jspf"%>