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12/20/2021

Spring Boot JSP View Resolver Example

 Learn to create and configure spring boot jsp view resolver which uses JSP template files to render view layer. This example uses embedded Tomcat server to run the application.

Sourcecode Structure

The files in this application are placed as given structure in image.


Maven dependencies – pom.xml

This application uses given below dependencies.

    <modelVersion>4.0.0</modelVersion>
    <groupId>com.howtodoinjava</groupId>
    <artifactId>spring-boot-demo</artifactId>
    <packaging>war</packaging>
    <version>0.0.1-SNAPSHOT</version>
    <name>spring-boot-demo Maven Webapp</name>
    <url>http://maven.apache.org</url>
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>1.5.1.RELEASE</version>
    </parent>
    <properties>
        <java.version>1.8</java.version>
    </properties>
    <dependencies>
        <!-- Web -->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <!-- Tomcat Embed -->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-tomcat</artifactId>
            <scope>provided</scope>
        </dependency>
        <!-- JSTL -->
        <dependency>
            <groupId>javax.servlet</groupId>
            <artifactId>jstl</artifactId>
        </dependency>
        <!-- To compile JSP files -->
        <dependency>
            <groupId>org.apache.tomcat.embed</groupId>
            <artifactId>tomcat-embed-jasper</artifactId>
            <scope>provided</scope>
        </dependency>
    </dependencies>
</project>

Spring Boot Application Initializer

The first step in producing a deployable war file is to provide a SpringBootServletInitializer subclass and override its configure() method. This makes use of Spring Framework’s Servlet 3.0 support and allows you to configure your application when it’s launched by the servlet container.

package com.howtodoinjava.app.controller;
 
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.boot.builder.SpringApplicationBuilder;
import org.springframework.boot.web.support.SpringBootServletInitializer;
 
@SpringBootApplication
public class SpringBootWebApplication extends SpringBootServletInitializer {
 
    @Override
    protected SpringApplicationBuilder configure(SpringApplicationBuilder application) {
        return application.sources(SpringBootWebApplication.class);
    }
 
    public static void main(String[] args) throws Exception {
        SpringApplication.run(SpringBootWebApplication.class, args);
    }
}

Spring Controller

Controller classes can have methods mapped to specific URLs in the application. In given application, it has two views i.e. “/” and “/next”.

package com.howtodoinjava.app.controller;
 
import java.util.Map;
 
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
 
@Controller
public class IndexController {
 
    @RequestMapping("/")
    public String home(Map<String, Object> model) {
        model.put("message", "HowToDoInJava Reader !!");
        return "index";
    }
     
    @RequestMapping("/next")
    public String next(Map<String, Object> model) {
        model.put("message", "You are in new page !!");
        return "next";
    }
 
}

Spring Boot JSP ViewResolver Configuration

To resolve JSP files location, you can have two approaches.

1) Add entries in application.properties

spring.mvc.view.prefix=/WEB-INF/view/
spring.mvc.view.suffix=.jsp
 
//For detailed logging during development
 
logging.level.org.springframework=TRACE
logging.level.com=TRACE

2) Configure InternalResourceViewResolver to serve JSP pages

package com.howtodoinjava.app.controller;
 
import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.servlet.config.annotation.EnableWebMvc;
import org.springframework.web.servlet.config.annotation.ViewResolverRegistry;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurerAdapter;
import org.springframework.web.servlet.view.InternalResourceViewResolver;
import org.springframework.web.servlet.view.JstlView;
 
@Configuration
@EnableWebMvc
@ComponentScan
public class MvcConfiguration extends WebMvcConfigurerAdapter
{
    @Override
    public void configureViewResolvers(ViewResolverRegistry registry) {
        InternalResourceViewResolver resolver = new InternalResourceViewResolver();
        resolver.setPrefix("/WEB-INF/view/");
        resolver.setSuffix(".jsp");
        resolver.setViewClass(JstlView.class);
        registry.viewResolver(resolver);
    }
}

JSP Files

Two used JSP files in this spring boot jsp example – are below.

index.jsp

<!DOCTYPE html>
<%@ taglib prefix="spring" uri="http://www.springframework.org/tags"%>
<html lang="en">
<body>
    <div>
        <div>
            <h1>Spring Boot JSP Example</h1>
            <h2>Hello ${message}</h2>
             
            Click on this <strong><a href="next">link</a></strong> to visit another page.
        </div>
    </div>
</body>
</html>

next.jsp

<!DOCTYPE html>
<%@ taglib prefix="spring" uri="http://www.springframework.org/tags"%>
<html lang="en">
<body>
    <div>
        <div>
            <h1>Another page</h1>
            <h2>Hello ${message}</h2>
             
            Click on this <strong><a href="/">link</a></strong> to visit previous page.
        </div>
    </div>
</body>
</html>

Demo

After whole code is written and placed inside folders, run the application by executing main() method in SpringBootWebApplication class.

Now hit the URL: http://localhost:8080/


Click next link


Spring Boot JSP example Source Code

Download the sourcecode of this application with below ink.

In this tutorial, we learned Spring Boot JSP ViewResolver with example, among other possible multiple view resolvers available to use.



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