Spring Boot总是返回404错误

Question

我试图获得一个Spring Boot(1.5.9)项目，以响应一个简单的Hello world消息。但是，我发送的任何请求都会立即返回404异常。

MyBackEndApplication

package net.mypackage.backend;

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

@SpringBootApplication
public class MyBackendApplication {

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

控制器/指挥机

package net.mypackage.backend.controllers;

import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.bind.annotation.RequestMapping;

@RestController
public class HelloController {

    @RequestMapping("/hello")
    public String sayHello() {
        return "Hello, world!";
    }

}

server.port = 5000
server.contextPath=/
logging.level.org=DEBUG

Build.Gradle

buildscript {
    ext {
        springBootVersion = '1.5.9.RELEASE'
    }
    repositories {
        mavenCentral()
    }
    dependencies {
        classpath("org.springframework.boot:spring-boot-gradle-plugin:${springBootVersion}")
    }
}

apply plugin: 'java'
apply plugin: 'eclipse'
apply plugin: 'org.springframework.boot'

group = 'net.mypackage'
version = '0.0.1-SNAPSHOT'
sourceCompatibility = 1.8

repositories {
    mavenCentral()
}


dependencies {
    compile('org.springframework.boot:spring-boot-starter-jersey')
    runtime('org.springframework.boot:spring-boot-devtools')
    testCompile('org.springframework.boot:spring-boot-starter-test')
    compile("org.springframework.boot:spring-boot-starter-actuator")
}

当请求一个页面(localhost:5000/hello)时，我得到一个404错误。以下信息显示在此请求的日志中（这里有一个要点，因为我不喜欢将其格式化为引号的方式）：

2018-02-05 13:01:37.600 DEBUG 17448---[nio-5000-exec-2]o.a.coyote.http11.http11inputbuffer:接收[GET/HTTP/1.1
缓存-控制：无缓存用户代理：PostmanRuntime/7.1.1 Accept://host:127.0.0.1:5000 Accept-Encoding:gzip,deflate Connection:keep-alive]2018-02-05 13:01:37.601 DEBUG 17448--[nio-5000-exec-2]O.A.C.Authenticator.AuthenticatorBase：安全检查请求GET/2018-02-05 13:01:37.601 DEBUG 17448--[nio-5000-exec-2]org.apache.catalina.realmBase：未定义适用的约束2018-02-05 13:01:37.601 DEBUG任何约束2018-02-05 13:01:37.604 DEBUG 17448----[nio-5000-exec-2]o.a.tomcat.util.net.socketwrapperbase:socket:[org.apache.tomcat.util.net.nioendpoint$niosocketwrapper@4bfc0a6:org.apache.tomcat.util.net.niochannel@b945368:java.nio.channels.socketchannel[connected local=/127.0.0.1:5000 G17448--[nio-5000-exec-2]O.apache.coyote.http11.http11Processor:Socket:[org.apache.tomcat.util.net.nioEndpoint$nioSocketWrapper@4bfc0a6:或g.apache.tomcat.util.net.nioChannel@b945368:java.nio.channels.socketChannel[connected local=/127.0.0.1:5000 remote=/127.0.0.1:53684]]，状态in:[OPEN_READ]，状态out:[OPEN]

我肯定我错过了一些非常基本的东西，但我一辈子都想不出来是什么。提前致谢：）

Answer 1

您提供的信息是不够的。

当我使用这个pom.xml尝试您的应用程序和控制器时：

<?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>mvc</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <packaging>jar</packaging>

    <name>MVC</name>
    <description>Demo project for Spring Boot</description>

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>1.5.9.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.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>

它可以与server.contextpath=/一起使用，也可以在注释掉时使用。