Exception while starting spring boot application as jar

Question

I created a jar using maven spring boot plugin and tried to run the jar using java -jar App.jar. The main file is configured with Spring boot and when I tried package it start the jar I am getting error as -

Exception in thread "main" java.lang.NoClassDefFoundError: org/springframework/boot/SpringApplication
        at com.database.DatabaseApplication.main(DatabaseApplication.java:12)
Caused by: java.lang.ClassNotFoundException: org.springframework.boot.SpringApplication
        at java.net.URLClassLoader.findClass(Unknown Source)
        at java.lang.ClassLoader.loadClass(Unknown Source)
        at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)
        at java.lang.ClassLoader.loadClass(Unknown Source)
        ... 1 more

This indicated that the dependency jar is missing in the packaged jar. I tried looking for various solutions on the web but to my failure none worked for me. I check the answer NoClassDefinitonFound and Package dependency jar but it did not work and I ended up getting the same error everytime. Below is the build section of my pom. Can anyone please help ?

Current configuration

<build>
    <plugins>
        <plugin>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-maven-plugin</artifactId>
            <executions>
               <execution>
                 <goals>
                   <goal>repackage</goal>
                 </goals>
                 <configuration>
                   <classifier>spring-boot</classifier>
                   <mainClass>${start-class}</mainClass>
                 </configuration>
               </execution>
             </executions>
        </plugin>
    </plugins>
</build>

Other configurations

<build>
<plugins>
    <plugin>
        <groupId>org.apache.maven.plugins</groupId>
        <artifactId>maven-shade-plugin</artifactId>
        <executions>
          <execution>
            <phase>package</phase>
            <goals>
              <goal>shade</goal>
            </goals>
            <configuration>
              <transformers>
                <transformer implementation="org.apache.maven.plugins.shade.resource.ManifestResourceTransformer">
                  <mainClass>${start-class}</mainClass>
                </transformer>
              </transformers>
            </configuration>
          </execution>
        </executions>
    </plugin>
</plugins>

<build>
<plugins>
    <plugin>
        <groupId>org.apache.maven.plugins</groupId>
        <artifactId>maven-dependency-plugin</artifactId>
        <executions>
            <execution>
                <id>copy-dependencies</id>
                <phase>prepare-package</phase>
                <goals>
                    <goal>copy-dependencies</goal>
                </goals>
                <configuration>
                    <outputDirectory>${project.build.directory}/lib</outputDirectory>
                    <overWriteReleases>false</overWriteReleases>
                    <overWriteSnapshots>false</overWriteSnapshots>
                    <overWriteIfNewer>true</overWriteIfNewer>
                </configuration>
            </execution>
        </executions>
    </plugin>
    <plugin>
        <groupId>org.apache.maven.plugins</groupId>
        <artifactId>maven-jar-plugin</artifactId>
        <configuration>
            <archive>
                <manifest>
                    <addClasspath>true</addClasspath>
                    <classpathPrefix>lib/</classpathPrefix>
                    <mainClass>${start-class}</mainClass>
                </manifest>
            </archive>
        </configuration>
    </plugin> 
</plugins>

Below is the pom.xml file without build added -

<?xml version="1.0" encoding="UTF-8"?>

http://maven.apache.org/xsd/maven-4.0.0.xsd"> 4.0.0

<groupId>com.database</groupId>
<artifactId>Database</artifactId>
<version>0.0.1</version>
<packaging>jar</packaging>

<name>Database application </name>
<description>Database operations application</description>

<parent>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-parent</artifactId>
    <version>2.0.0.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>
    <start-class>com.database.App</start-class>
    <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-web</artifactId>
    </dependency>
    <dependency>
      <groupId>mysql</groupId>
      <artifactId>mysql-connector-java</artifactId>
    </dependency>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-tomcat</artifactId>
        <scope>provided</scope>
    </dependency>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-devtools</artifactId>
        <scope>runtime</scope>
    </dependency>               
    <dependency>
        <groupId>org.apache.poi</groupId>
        <artifactId>poi</artifactId>
        <version>3.17</version>
    </dependency>
    <dependency>
        <groupId>org.apache.poi</groupId>
        <artifactId>poi-ooxml-schemas</artifactId>
        <version>3.17</version>
    </dependency>
    <dependency>
        <groupId>org.apache.poi</groupId>
        <artifactId>poi-ooxml</artifactId>
        <version>3.17</version>
    </dependency>
</dependencies>

<build>
    ...
</build>

I want to package dependencies into the jar file created after running mvn clean package. Using terminal to build the application and not building it using eclipse.

Do you use maven, right? If yes put here you pom.xml file :) — Dina Bogdan, Apr 13 '18 at 07:17

score 0 · Answer 1 · answered Apr 13 '18 at 08:39

Please, use this configuration for build section in your pom.xml.

<build>
    <plugins>
        <plugin>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-maven-plugin</artifactId>
        </plugin>
    </plugins>
</build>

Exception while starting spring boot application as jar

1 Answers1