弹簧启动-Whitelabel错误页面

Question

package com.example.demo;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.boot.autoconfigure.security.SecurityAutoConfiguration;
import org.springframework.context.annotation.ComponentScan;


@SpringBootApplication(exclude = SecurityAutoConfiguration.class)
@ComponentScan
public class SpringbootdemoApplication {

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

controller:

package com.example.controller;
import java.util.ArrayList;
import java.util.List;

import org.springframework.http.MediaType;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RestController;
import com.example.module.*;


@RestController
public class EmployeeController 
{
    @RequestMapping(value="/getemp", method = RequestMethod.GET)
    public List<Employee> getEmployees() 
    {
        List<Employee> employeesList = new ArrayList<Employee>();
        employeesList.add(new Employee(1,"lokesh","gupta","howtodoinjava@gmail.com"));
        return employeesList;
    }
}

bean:

package com.example.module;

public class Employee {

    public Employee() {

    }
    public Employee(Integer id, String firstName, String lastName, String email) {
        super();
        this.id = id;
        this.firstName = firstName;
        this.lastName = lastName;
        this.email = email;
    }

    private Integer id;
    private String firstName;
    private String lastName;
    private String email;

    public Integer getId() {
        return id;
    }
    public void setId(Integer id) {
        this.id = id;
    }
    public String getFirstName() {
        return firstName;
    }
    public void setFirstName(String firstName) {
        this.firstName = firstName;
    }
    public String getLastName() {
        return lastName;
    }
    public void setLastName(String lastName) {
        this.lastName = lastName;
    }
    public String getEmail() {
        return email;
    }
    public void setEmail(String email) {
        this.email = email;
    }

    @Override
    public String toString() {
        return "Employee [id=" + id + ", firstName=" + firstName
                + ", lastName=" + lastName + ", email=" + email + "]";
    }
}

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.demo</groupId>
    <artifactId>springbootdemo</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <packaging>jar</packaging>

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

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>1.4.3.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-data-jpa</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-hateoas</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-jersey</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-security</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>

        <dependency>
            <groupId>org.hsqldb</groupId>
            <artifactId>hsqldb</artifactId>
            <scope>runtime</scope>
        </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>

error: Whitelabel Error Page

This application has no explicit mapping for /error, so you are seeing this as a fallback.

Thu Jan 19 15:27:39 IST 2017 There was an unexpected error (type=Not Found, status=404). No message available

i am new to spring boot.plese help me to solve this error

Answer 1

I think the problem is related with the @ComponentScan and the packaging. If specific packages are not defined, scanning will occur from the package of the class that declares this annotation. Try to change the package of your class SpringbootdemoApplication from:

package com.example.demo;

... to this one:

package com.example;

Answer 2

you no more need @ComponentScan as it's already into @SpringBootApplication

on the other side, the error is related to the fact the you didn't provide fall back to the application root context /

Answer 3

This is because Spring Boot scans the package under package com.example.demo . Change the package name of EmployeeController from com.example.controller to com.example.demo.controller