Step08.md

What You Will Learn during this Step:

• Add validation for userid and password
• Hard coded validation!!

Useful Snippets and References

First Snippet

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");
    }
}

Second Snippet

    @Autowired
    private LoginService service;

    @RequestMapping(value = "/login", method = RequestMethod.POST)
    public String handleLogin(ModelMap model, @RequestParam String name,
            @RequestParam String password) {

        boolean isValidUser = service.validateUser(name, password);

        if (isValidUser) {
            model.put("name", name);
            return "welcome";
        } else {
            model.put("errorMessage", "Invalid Credentials!!");
            return "login";
        }
    }

Files List

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 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>

	<name>spring-boot-first-web-application</name>
	<description>Demo project for Spring Boot</description>

	<parent>
		<groupId>org.springframework.boot</groupId>
		<artifactId>spring-boot-starter-parent</artifactId>
		<version>1.4.3.RELEASE</version>
		<relativePath/> <!-- lookup parent from repository -->
	</parent>

	<properties>
		<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
		<project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
		<java.version>1.8</java.version>
	</properties>

	<dependencies>
		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-web</artifactId>
		</dependency>
		
		<dependency>
            <groupId>org.apache.tomcat.embed</groupId>
            <artifactId>tomcat-embed-jasper</artifactId>
            <scope>provided</scope>
        </dependency>
		
		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-devtools</artifactId>
			<scope>runtime</scope>
		</dependency>
		
		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-test</artifactId>
			<scope>test</scope>
		</dependency>
	</dependencies>

	<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/LoginController.java

package com.in28minutes.springboot.web.controller;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.ui.ModelMap;
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.service.LoginService;

@Controller
public class LoginController {
	
	@Autowired
	LoginService service;
	
	@RequestMapping(value="/login", method = RequestMethod.GET)
	public String showLoginPage(ModelMap model){
		return "login";
	}
	
	@RequestMapping(value="/login", method = RequestMethod.POST)
	public String showWelcomePage(ModelMap model, @RequestParam String name, @RequestParam String password){
		boolean isValidUser = service.validateUser(name, password);
		
		if (!isValidUser) {
			model.put("errorMessage", "Invalid Credentials");
			return "login";
		}
		
		model.put("name", name);
		model.put("password", password);
		
		return "welcome";
	}

}

---

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 userid, String password) {
		// in28minutes, dummy
		return userid.equalsIgnoreCase("in28minutes")
				&& password.equalsIgnoreCase("dummy");
	}

}

---

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

package com.in28minutes.springboot.web;

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

@SpringBootApplication
public class SpringBootFirstWebApplication {

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

---

src/main/resources/application.properties

spring.mvc.view.prefix=/WEB-INF/jsp/
spring.mvc.view.suffix=.jsp
logging.level.org.springframework.web=DEBUG

---

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

<html>

<head>
<title>First Web Application</title>
</head>

<body>
	<font color="red">${errorMessage}</font>
	<form method="post">
		Name : <input type="text" name="name" />
		Password : <input type="password" name="password" /> 
		<input type="submit" />
	</form>
</body>

</html>

---

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

<html>

<head>
<title>First Web Application</title>
</head>

<body>
	Welcome ${name}!!
</body>

</html>

---

src/test/java/com/in28minutes/springboot/web/SpringBootFirstWebApplicationTests.java

package com.in28minutes.springboot.web;

import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.test.context.junit4.SpringRunner;

@RunWith(SpringRunner.class)
@SpringBootTest
public class SpringBootFirstWebApplicationTests {

	@Test
	public void contextLoads() {
	}

}

---

todo.txt

Component, Service, Repository, Controller
Autowired
ComponentScan


Spring Boot Starter Parent
Spring Boot Starter Web
@SpringBootApplication
Auto Configuration

Dispatcher Servlet

/login => "login"

"login" => src/main/webapp/WEB-INF/jsp/login.jsp 


Search for a view named "login"



/login => LoginController 

---