我在这里有一个非常简单的Spring-Boot MVC应用程序无效。一个控制器,其中一页未加载并且未找到404。
我在控制器方法中放置了一个System.out.println(“Home Page”)语句,并验证它是否已映射并正确触发,但模板未加载。
错误:
Whitelabel Error Page
This application has no explicit mapping for /error, so you are seeing this as a fallback.
Thu Nov 06 23:43:51 EST 2014
There was an unexpected error (type=Not Found, status=404).
文件夹结构:
src/main/java
+-Application.java
+-WebController.java
src/main/resources
+-templates
+-index.html
缩略控制台输出:
Server initialized with port: 8080
Starting service Tomcat
Starting Servlet Engine: Apache Tomcat/7.0.55
Initializing Spring embedded WebApplicationContext
Root WebApplicationContext: initialization completed in 1947 ms
Mapping servlet: 'dispatcherServlet' to [/]
Mapping filter: 'hiddenHttpMethodFilter' to: [/*]
Mapped "{[/],methods=[],params=[],headers=[],consumes=[],produces=[],custom=[]}" onto public java.lang.String app.WebController.index()
Tomcat started on port(s): 8080/http
Started Application in 5.552 seconds (JVM running for 6.366)
Home Page
Home Page
Home Page
配置:
@EnableAutoConfiguration
@Configuration
@ComponentScan
public class Application extends WebMvcConfigurerAdapter {
public static void main(String[] args) {
ConfigurableApplicationContext context = SpringApplication.run(Application.class);
}
}
控制器:
@Controller
public class WebController {
@RequestMapping(value="/")
public String index(){
System.out.println("Home Page");
return "index";
}
}
index.html:
<!DOCTYPE html>
<html lang="en">
<body>
<h1>Hello</h1>
</body>
</html>
我在这里有一个非常简单的Spring-Boot MVC应用程序无效。一个控制器,其中一页未加载并且未找到404。
我在控制器方法中放置了一个System.out.println(“Home Page”)语句,并验证它是否已映射并正确触发,但模板未加载。
错误:
Whitelabel Error Page
This application has no explicit mapping for /error, so you are seeing this as a fallback.
Thu Nov 06 23:43:51 EST 2014
There was an unexpected error (type=Not Found, status=404).
文件夹结构:
src/main/java
+-Application.java
+-WebController.java
src/main/resources
+-templates
+-index.html
缩略控制台输出:
Server initialized with port: 8080
Starting service Tomcat
Starting Servlet Engine: Apache Tomcat/7.0.55
Initializing Spring embedded WebApplicationContext
Root WebApplicationContext: initialization completed in 1947 ms
Mapping servlet: 'dispatcherServlet' to [/]
Mapping filter: 'hiddenHttpMethodFilter' to: [/*]
Mapped "{[/],methods=[],params=[],headers=[],consumes=[],produces=[],custom=[]}" onto public java.lang.String app.WebController.index()
Tomcat started on port(s): 8080/http
Started Application in 5.552 seconds (JVM running for 6.366)
Home Page
Home Page
Home Page
配置:
@EnableAutoConfiguration
@Configuration
@ComponentScan
public class Application extends WebMvcConfigurerAdapter {
public static void main(String[] args) {
ConfigurableApplicationContext context = SpringApplication.run(Application.class);
}
}
控制器:
@Controller
public class WebController {
@RequestMapping(value="/")
public String index(){
System.out.println("Home Page");
return "index";
}
}
index.html:
<!DOCTYPE html>
<html lang="en">
<body>
<h1>Hello</h1>
</body>
</html>
POM:
<?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.App</groupId>
<artifactId>App</artifactId>
<version>0.0.1-SNAPSHOT</version>
<name>App</name>
<description>App</description>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>1.1.8.RELEASE</version>
</parent>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-data-jpa</artifactId>
</dependency>
<dependency>
<groupId>com.h2database</groupId>
<artifactId>h2</artifactId>
<version>1.4.181</version>
</dependency>
<!--dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-redis</artifactId>
</dependency-->
<dependency>
<groupId>com.firebase</groupId>
<artifactId>firebase-client</artifactId>
<version>1.0.1</version>
</dependency>
<dependency>
<groupId>org.scala-lang</groupId>
<artifactId>scala-library</artifactId>
<version>2.10.4</version>
</dependency>
</dependencies>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<start-class>App.Application</start-class>
<java.version>1.7</java.version>
</properties>
<repositories>
<repository>
<id>spring-releases</id>
<name>Spring Releases</name>
<url>http://repo.spring.io/libs-release</url>
</repository>
</repositories>
<pluginRepositories>
<pluginRepository>
<id>spring-releases</id>
<name>Spring Releases</name>
<url>http://repo.spring.io/libs-release</url>
</pluginRepository>
</pluginRepositories>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
</plugins>
</build>
</project>
答案 0 :(得分:49)
看起来你没有在你的课程路径上有Thymeleaf。
添加此依赖项:
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-thymeleaf</artifactId>
</dependency>
然后一切都应该工作。
如果您仍然遇到某些问题,我建议您使用http://start.spring.io/
创建新项目答案 1 :(得分:2)
点击此链接。给出了一个例子 http://spring.io/guides/gs/handling-form-submission/
的src /主/ JAVA /你好/ GreetingController.java
package hello;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.ModelAttribute;
import org.springframework.web.bind.annotation.PostMapping;
@Controller
public class GreetingController {
@GetMapping("/greeting")
public String greetingForm(Model model) {
model.addAttribute("greeting", new Greeting());
return "greeting";
}
@PostMapping("/greeting")
public String greetingSubmit(@ModelAttribute Greeting greeting) {
return "result";
}
}
的src /主/资源/模板/ greeting.html
<html xmlns:th="http://www.thymeleaf.org">
<head>
<title>Getting Started: Handling Form Submission</title>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />
</head>
<body>
<h1>Form</h1>
<form action="#" th:action="@{/greeting}" th:object="${greeting}" method="post">
<p>Id: <input type="text" th:field="*{id}" /></p>
<p>Message: <input type="text" th:field="*{content}" /></p>
<p><input type="submit" value="Submit" /> <input type="reset" value="Reset" /></p>
</form>
</body>
</html>
的src /主/资源/模板/ result.html
<!DOCTYPE HTML>
<html xmlns:th="http://www.thymeleaf.org">
<head>
<title>Getting Started: Handling Form Submission</title>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />
</head>
<body>
<h1>Result</h1>
<p th:text="'id: ' + ${greeting.id}" />
<p th:text="'content: ' + ${greeting.content}" />
<a href="/greeting">Submit another message</a>
</body>
</html>
的src /主/ JAVA /你好/ Application.java
package hello;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
@SpringBootApplication
public class Application {
public static void main(String[] args) {
SpringApplication.run(Application.class, args);
}
}
答案 2 :(得分:1)
尝试从这个网站http://start.spring.io/创建一个spring boot项目,这是一个spring初始化程序,用于创建一个带有spring boot的maven项目。添加web和thymeleaf依赖项并生成项目。将项目作为maven项目导入IDE中,或使用Spring工具套件。
DemoApplication.java:
@Controller
@SpringBootApplication
public class DemoApplication {
public static void main(String[] args) {
SpringApplication.run(DemoApplication.class, args);
}
@RequestMapping(value = "/homepage" , method = RequestMethod.GET )
public String sample()
{
return "home";
}
}
的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.example</groupId>
<artifactId>demo</artifactId>
<version>0.0.1-SNAPSHOT</version>
<packaging>jar</packaging>
<name>demo</name>
<description>Demo project for Spring Boot</description>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>1.4.2.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>1.7</java.version>
</properties>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-thymeleaf</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</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>
home.html的:
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8"></meta>
<title>HomePage</title>
</head>
<body>
<h1>MY Spring Boot Home Page</h1>
</body>
</html>
答案 3 :(得分:0)
这是一个极端情况,是偶然的。但是,可能是一个可能的原因。
确保没有更改application.properties
中的静态资源路径,例如:
spring.resources.static-locations=classpath:/META-INF/resources/,classpath:/META-INF/resources/webjars/
我将此属性用于SwaggerUI,该属性还有其他解决方法。 删除此属性有效。