Spring Boot MVC not using model values in JSP

2019-07-28 19:11发布

问题:

I am working on an Spring Boot MVC application. My issue is that when the view appears, it does not parse the values from the Model.

application.properties

spring.application.name=test-mvc
server.context-path=/test-mvc

Config

@Configuration
@EnableWebMvc
public class ApplicationConfigurerAdapter extends WebMvcConfigurerAdapter{

    @Override
    public void configureDefaultServletHandling(DefaultServletHandlerConfigurer configurer) {
        configurer.enable();
    }

    @Bean
    public InternalResourceViewResolver viewResolver() {
        InternalResourceViewResolver resolver = new InternalResourceViewResolver();
        resolver.setPrefix("/WEB-INF/pages/");
        resolver.setSuffix(".jsp");

        return resolver;
    }
}

Application

@SpringBootApplication
public class Application extends SpringBootServletInitializer {
    @Override
    protected SpringApplicationBuilder configure(SpringApplicationBuilder application) {
        return application.sources(Application.class);
    }

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

Controller

@Controller
@RequestMapping("/view")
public class TestController {

    @RequestMapping("/greeting")
    public String greeting(@RequestParam(value="name", required=false, defaultValue="World") String name, ModelMap model) {
        model.addAttribute("name", name);

        return "greeting";
    }
}

greeting.jsp

<html>
 <head><title>Hello world Example</title></head>
 <body>
     <h1>Hello ${name}, How are you?</h1>
 </body>
</html> 

Output from http://localhost:8080/test-mvc/view/greeting?name=Mikey:

Hello ${name}, How are you?

I have also tried returning a ModelAndView. I am not sure why it's not putting "Mikey" in where ${name} is.

Update

Every time I add a taglib or anything to the JSP page, it displays the page source. It doesn't render the page. Below is my pom.xml

<parent>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-parent</artifactId>
    <version>1.3.3.RELEASE</version>
</parent>

<properties>
    <hibernate.version>5.0.5.Final</hibernate.version>
    <postgres.version>9.4.1208</postgres.version>
</properties>

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

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

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

    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-log4j</artifactId>
    </dependency>

    <dependency>
        <groupId>org.hibernate</groupId>
        <artifactId>hibernate-validator</artifactId>
    </dependency>

    <dependency>
        <groupId>org.postgresql</groupId>
        <artifactId>postgresql</artifactId>
    </dependency>

    <dependency>
        <groupId>jstl</groupId>
        <artifactId>jstl</artifactId>
        <version>1.2</version>
    </dependency>

    <dependency>
        <groupId>javax.servlet</groupId>
        <artifactId>javax.servlet-api</artifactId>
    </dependency>

    <dependency>
        <groupId>org.apache.taglibs</groupId>
        <artifactId>taglibs-standard-impl</artifactId>
        <version>1.2.5</version>
    </dependency>
</dependencies>

回答1:

Add below dependencies in your pom.xml:

    <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>

You might have to add below dependency to avoid javax.servlet.ServletException: java.lang.NoSuchMethodError: org.apache.el.lang.ELSupport.coerceToType. If you don't add this as scope=required then tomcat-embed-el-8.0.32.jar will be placed in your Tomcat 8.0\webapps\AppName\WEB-INF\lib folder and will cause above error. You don't need to add below dependency if you run your app from IDE or mvn Spring-boot:run command.

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

Then visit - http://localhost:8080/AppName/view/greeting?name=Mikey

Check this repo for Complete Source Code.

UPDATE: The issue Tomcat war deployment of JSP sample is not working due to "tomcat-embed-el" dependency is fixed in Spring Boot - 1.4.0.M2