Spring Boot Application War Deployment- 404 Not Found

I have created a war file from my Spring Boot application and deployed into Tomcat server, but it gives 404: not found error. The application works perfectly when run using the IDE embedded server. To convert the application to war, I have done the following:

1- Change Application class to:

@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);
    }

}

2- Modified pom.xml and changed spring-boot-starter-tomcat to provided

I created the war file using mvn clean package -Pproduction command

To identify the homepage, I use this tag: @RouteAlias(value = “”)

Any help is appreciated.

Do the Tomcat logs give any hints?

Artur Signell:
Do the Tomcat logs give any hints?

I have viewed the logs and haven’t seen any issue there

If you take a starter app from start.vaadin.com what you need to change is:

  1. packaging in pom.xml from jar to war
  2. exclude spring-boot-starter-tomcat e.g. by making it provided

Maybe you can try that and see if it works the same or differently.

Another issue I have run into is compiling the project with a newer JDK than the server is running on. Sometimes this results in just nothing being deployed.

Artur Signell:
If you take a starter app from start.vaadin.com what you need to change is:

  1. packaging in pom.xml from jar to war
  2. exclude spring-boot-starter-tomcat e.g. by making it provided

Maybe you can try that and see if it works the same or differently.

Another issue I have run into is compiling the project with a newer JDK than the server is running on. Sometimes this results in just nothing being deployed.

Surprisingly, I am getting the same error message with the starter app. So, the problem is most likely related to tomcat. I will try it on a different server and let you know.

I tried to run the starter project using eclipse’s embedded Tomcat server and I am getting the same error, see the attached image. This is my Application class:

package com.example.application;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.boot.builder.SpringApplicationBuilder;
import org.springframework.boot.web.servlet.support.SpringBootServletInitializer;


/**
 * The entry point of the Spring Boot 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);
    }

}

And this is my pom.xml file:

<?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.application</groupId>
    <artifactId>myapp</artifactId>
    <name>Project base for Spring Boot and Vaadin Flow</name>
    <packaging>war</packaging>

    <properties>
        <start-class>com.example.application.Application</start-class>
        <java.version>8</java.version>
        <vaadin.version>14.5.2</vaadin.version>
    </properties>

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.4.4</version>
    </parent>

    <repositories>
        <!-- The order of definitions matters. Explicitly defining central here to make sure it has the highest priority. -->

        <!-- Main Maven repository -->
        <repository>
            <id>central</id>
            <url>https://repo.maven.apache.org/maven2</url>
            <snapshots>
                <enabled>false</enabled>
            </snapshots>
        </repository>
        <!-- Repository used by many Vaadin add-ons -->
        <repository>
            <id>Vaadin Directory</id>
            <url>https://maven.vaadin.com/vaadin-addons</url>
            <snapshots>
                <enabled>false</enabled>
            </snapshots>
        </repository>
    </repositories>

    <pluginRepositories>
        <!-- Main Maven repository -->
        <pluginRepository>
            <id>central</id>
            <url>https://repo.maven.apache.org/maven2</url>
            <snapshots>
                <enabled>false</enabled>
            </snapshots>
        </pluginRepository>
    </pluginRepositories>

    <dependencyManagement>
        <dependencies>
            <dependency>
                <groupId>com.vaadin</groupId>
                <artifactId>vaadin-bom</artifactId>
                <version>${vaadin.version}</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
        </dependencies>
    </dependencyManagement>

    <dependencies>
        <dependency>
            <groupId>com.vaadin</groupId>
            <!-- Replace artifactId with vaadin-core to use only free components -->
            <artifactId>vaadin</artifactId>
            <exclusions>
                <!-- Webjars are only needed when running in Vaadin 13 compatibility mode -->
                <exclusion>
                    <groupId>com.vaadin.webjar</groupId>
                    <artifactId>*</artifactId>
                </exclusion>
                <exclusion>
                    <groupId>org.webjars.bowergithub.insites</groupId>
                    <artifactId>*</artifactId>
                </exclusion>
                <exclusion>
                    <groupId>org.webjars.bowergithub.polymer</groupId>
                    <artifactId>*</artifactId>
                </exclusion>
                <exclusion>
                    <groupId>org.webjars.bowergithub.polymerelements</groupId>
                    <artifactId>*</artifactId>
                </exclusion>
                <exclusion>
                    <groupId>org.webjars.bowergithub.vaadin</groupId>
                    <artifactId>*</artifactId>
                </exclusion>
                <exclusion>
                    <groupId>org.webjars.bowergithub.webcomponents</groupId>
                    <artifactId>*</artifactId>
                </exclusion>
            </exclusions>
        </dependency>
        <dependency>
            <groupId>com.vaadin</groupId>
            <artifactId>vaadin-spring-boot-starter</artifactId>
            <exclusions>
                <!-- Excluding so that webjars are not included. -->
                <exclusion>
                    <groupId>com.vaadin</groupId>
                    <artifactId>vaadin-core</artifactId>
                </exclusion>
            </exclusions>
        </dependency>
           <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-tomcat</artifactId>
            <scope>provided</scope>
        </dependency>
        <dependency>
            <groupId>org.vaadin.artur</groupId>
            <artifactId>a-vaadin-helper</artifactId>
            <version>1.6.0</version>
        </dependency>

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

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-devtools</artifactId>
            <optional>true</optional>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>com.vaadin</groupId>
            <artifactId>vaadin-testbench</artifactId>
            <scope>test</scope>
        </dependency>
        <!-- Include JUnit 4 support for TestBench and others -->
        <dependency>
            <groupId>org.junit.vintage</groupId>
            <artifactId>junit-vintage-engine</artifactId>
            <scope>test</scope>
            <exclusions>
                <exclusion>
                    <groupId>org.hamcrest</groupId>
                    <artifactId>hamcrest-core</artifactId>
                </exclusion>
            </exclusions>
        </dependency>
        <dependency>
            <groupId>io.github.bonigarcia</groupId>
            <artifactId>webdrivermanager</artifactId>
            <version>3.8.1</version>
            <scope>test</scope>
        </dependency>
    </dependencies>

    <build>
        <defaultGoal>spring-boot:run</defaultGoal>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
                <!-- Clean build and startup time for Vaadin apps sometimes may exceed
                     the default Spring Boot's 30sec timeout.  -->
                <configuration>
                    <wait>500</wait>
                    <maxAttempts>240</maxAttempts>
                </configuration>
            </plugin>

            <!--
                Take care of synchronizing java dependencies and imports in
                package.json and main.js files.
                It also creates webpack.config.js if not exists yet.
            -->
            <plugin>
                <groupId>com.vaadin</groupId>
                <artifactId>vaadin-maven-plugin</artifactId>
                <version>${vaadin.version}</version>
                <executions>
                    <execution>
                        <goals>
                            <goal>prepare-frontend</goal>
                        </goals>
                    </execution>
                </executions>
            </plugin>
        </plugins>
    </build>

    <profiles>
        <profile>
            <!-- Production mode is activated using -Pproduction -->
            <id>production</id>
            <build>
                <plugins>
                    <plugin>
                        <groupId>com.vaadin</groupId>
                        <artifactId>vaadin-maven-plugin</artifactId>
                        <version>${vaadin.version}</version>
                        <executions>
                            <execution>
                                <goals>
                                    <goal>build-frontend</goal>
                                </goals>
                                <phase>compile</phase>
                            </execution>
                        </executions>
                        <configuration>
                            <productionMode>true</productionMode>
                        </configuration>
                    </plugin>
                </plugins>
            </build>
        </profile>

        <profile>
            <id>it</id>
            <build>
                <plugins>
                    <plugin>
                        <groupId>org.springframework.boot</groupId>
                        <artifactId>spring-boot-maven-plugin</artifactId>
                        <executions>
                            <execution>
                                <id>start-spring-boot</id>
                                <phase>pre-integration-test</phase>
                                <goals>
                                    <goal>start</goal>
                                </goals>
                            </execution>
                            <execution>
                                <id>stop-spring-boot</id>
                                <phase>post-integration-test</phase>
                                <goals>
                                    <goal>stop</goal>
                                </goals>
                            </execution>
                        </executions>
                    </plugin>

                    <!-- Runs the integration tests (*IT) after the server is started -->
                    <plugin>
                        <groupId>org.apache.maven.plugins</groupId>
                        <artifactId>maven-failsafe-plugin</artifactId>
                        <executions>
                            <execution>
                                <goals>
                                    <goal>integration-test</goal>
                                    <goal>verify</goal>
                                </goals>
                            </execution>
                        </executions>
                        <configuration>
                            <trimStackTrace>false</trimStackTrace>
                            <enableAssertions>true</enableAssertions>
                        </configuration>
                    </plugin>
                </plugins>
            </build>
        </profile>

    </profiles>
</project>

I made sure that both the project and tomcat server use the same JDK. I am not sure what to do here, please advise.

18571891.png

Normally you should have an error in your logs/catalina.out when you run/deploy the application.

You can also exclude the tomcat embedded with Spring boot, it can cause a conflict if you are using a different version. For example if you are trying on tomcat8. You have this kind of error:

java.lang.NoSuchMethodError: javax.servlet.http.HttpServletRequest.getHttpServletMapping()Ljavax/servlet/http/HttpServletMapping;

You can add/merge this in your pom.xml:

        <!-- Spring -->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter</artifactId>
            <exclusions>
                <exclusion>
                    <groupId>org.springframework.boot</groupId>
                    <artifactId>spring-boot-starter-tomcat</artifactId>
                </exclusion>
                <exclusion>
                    <groupId>org.springframework.boot</groupId>
                    <artifactId>spring-boot-starter-logging</artifactId>
                </exclusion>
            </exclusions>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-tomcat</artifactId>
            <scope>provided</scope>
        </dependency>

Are you using Tomcat 10?

Olli Tietäväinen:
Are you using Tomcat 10?

Yes, switching to Tomcat 9 fixed the problem :slight_smile: