Spring Boot REST接口出现HTTP 404错误，请求资源不可用求助

问题描述 #

创建了一个Spring Boot REST应用，通过「Run on server」运行时，浏览器会重定向到包含context-path的URL，但调用自定义接口时抛出HTTP 404 - 请求资源不可用错误，尝试多种方法未解决。

控制器代码 #

package in.ineuron.controller;

import java.time.LocalDateTime;

import org.springframework.http.HttpStatus;    
import org.springframework.http.HttpStatusCode;    
import org.springframework.http.ResponseEntity;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

import in.ineuron.response.CurrencyResponse;

@RestController
@RequestMapping("/api/currency")
public class CurrencyController {

@GetMapping("/getCurrencyValue/from/{from}/to/{to}")
public ResponseEntity<CurrencyResponse> getCurrencyValue(@PathVariable String from,
        @PathVariable String to){
    CurrencyResponse response=new CurrencyResponse();
    response.setCurrencyId(1);
    response.setCurrencyFrom(from);
    response.setCurrencyTo(to);
    response.setCurrencyValue(82);
    return new ResponseEntity<CurrencyResponse>(response, HttpStatus.OK);   
}

@GetMapping("/wish")
public ResponseEntity<String> wishMessage(){
    LocalDateTime ldt=LocalDateTime.now();
    int hour=ldt.getHour();
    String body=null;
    if(hour<12)
        body="Good Morning";
    else if(hour<16)
        body="Good Noon";
    else if(hour<20)
        body="Good evening";
    else
        body="Good Night";
    return new ResponseEntity<String>(body, HttpStatus.OK);
    
}

}

Pom.xml配置 #

<?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 https://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<parent>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-parent</artifactId>
    <version>3.1.6</version>
    <relativePath/> <!-- lookup parent from repository -->
</parent>
<groupId>in.ineuron</groupId>
<artifactId>1.SpringRest-WebclientProducerApp</artifactId>
<version>0.0.1-SNAPSHOT</version>
<name>1.SpringRest-WebclientProducerApp</name>
<description>Webclient ProducerApp</description>
<properties>
    <java.version>17</java.version>
</properties>
<dependencies>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter</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-web</artifactId>
    </dependency>
    <dependency>
        <groupId>org.projectlombok</groupId>
        <artifactId>lombok</artifactId>
        <optional>true</optional>
    </dependency>
</dependencies>

<build>
    <plugins>
        <plugin>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-maven-plugin</artifactId>
            <configuration>
                <image>
                    <builder>paketobuildpacks/builder-jammy-base:latest</builder>
                </image>
            </configuration>
        </plugin>
    </plugins>
</build>

</project>

测试请求URL #

• http://localhost:8081/1.SpringRest-WebclientProducerApp/api/currency/getCurrencyValue/from/USD/to/INR
• http://localhost:8081/1.SpringRest-WebclientProducerApp/api/currency/wish

报错信息 #

HTTP Status 404 – Not Found，请求的资源[/1.SpringRest-WebclientProducerApp/api/currency/wish]不可用

排查与解决方法 #

1. 检查启动类位置
   确保带@SpringBootApplication注解的启动类位于in.ineuron根包下，否则Spring无法自动扫描到控制器。若启动类在子包，需手动添加@ComponentScan(basePackages = "in.ineuron")注解。

2. 确认context-path配置
   Spring Boot默认无context-path，URL中的/1.SpringRest-WebclientProducerApp可能是Tomcat自动添加的项目名。可在application.properties中显式配置：

   server.servlet.context-path=/1.SpringRest-WebclientProducerApp
   

   或直接去掉该部分，用http://localhost:8081/api/currency/wish测试。

3. 验证端口正确性
   查看启动日志中的Tomcat started on port(s): 8081 (http)信息，确认应用确实运行在8081端口，避免端口冲突。

4. 检查控制器注解
   确保@RestController、@RequestMapping、@GetMapping注解无拼写错误，路径配置符合预期。

5. 清理重构项目
   执行mvn clean install清理缓存，重新构建后启动，避免编译或打包问题导致控制器未加载。

内容的提问来源于stack exchange，提问作者DhivyaViswanatha