Java 找不到合适的主类，请添加'mainClass'属性，Spring boot
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Unable to find a suitable main class, please add a 'mainClass' property, Spring boot
提问by Qasim
Hi friends i am developing a spring boot maven based project and and i have created a maven submodules but when i try to run my project it gives an error
嗨，朋友们，我正在开发一个基于 Spring Boot Maven 的项目，并且我已经创建了一个 Maven 子模块，但是当我尝试运行我的项目时，它给出了一个错误
[ERROR] Failed to execute goal org.springframework.boot:spring-boot-maven-plugin:1.2.5.RELEASE:run (default-cli) on project demo-jhipster: Unable to find a suitable main class, please add a 'mainClass' property -> [Help 1]
org.apache.maven.lifecycle.LifecycleExecutionException: Failed to execute goal org.springframework.boot:spring-boot-maven-plugin:1.2.5.RELEASE:run (default-cli) on project demo-jhipster: Unable to find a suitable main class, please add a 'mainClass' property
at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:216)
at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:153)
at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:145)
at org.apache.maven.lifecycle.internal.LifecycleModuleBuilder.buildProject(LifecycleModuleBuilder.java:116)
at org.apache.maven.lifecycle.internal.LifecycleModuleBuilder.buildProject(LifecycleModuleBuilder.java:80)
at org.apache.maven.lifecycle.internal.builder.singlethreaded.SingleThreadedBuilder.build(SingleThreadedBuilder.java:51)
at org.apache.maven.lifecycle.internal.LifecycleStarter.execute(LifecycleStarter.java:120)
at org.apache.maven.DefaultMaven.doExecute(DefaultMaven.java:355)
at org.apache.maven.DefaultMaven.execute(DefaultMaven.java:155)
at org.apache.maven.cli.MavenCli.execute(MavenCli.java:584)
at org.apache.maven.cli.MavenCli.doMain(MavenCli.java:216)
at org.apache.maven.cli.MavenCli.main(MavenCli.java:160)
my parent pom and child pom is
我的父 pom 和子 pom 是
<?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/maven-v4_0_0.xsd">
<modelVersion>4.0.0</modelVersion>
<parent>
<artifactId>spring-boot-starter-parent</artifactId>
<groupId>org.springframework.boot</groupId>
<version>1.2.5.RELEASE</version>
<relativePath />
</parent>
<groupId>com.aquevix.demo</groupId>
<artifactId>demo-jhipster</artifactId>
<version>0.0.1-SNAPSHOT</version>
<packaging>pom</packaging>
<name>demo_jhipster</name>
<prerequisites>
<maven>3.0.0</maven>
</prerequisites>
<modules>
<module>JhipsterSubmodule</module>
</modules>
<properties>
<assertj-core.version>3.1.0</assertj-core.version>
<awaitility.version>1.4.0</awaitility.version>
<commons-io.version>2.4</commons-io.version>
<commons-lang.version>2.6</commons-lang.version>
<gatling-maven-plugin.version>2.1.6</gatling-maven-plugin.version>
<gatling.version>2.1.6</gatling.version>
<hibernate.version>4.3.10.Final</hibernate.version>
<hikaricp.version>2.4.0</hikaricp.version>
<jacoco-maven-plugin.version>0.7.4.201502262128</jacoco-maven-plugin.version>
<java.version>1.8</java.version>
<javax.inject.version>1</javax.inject.version>
<joda-time-hibernate.version>1.4</joda-time-hibernate.version>
<liquibase-hibernate4.version>3.5</liquibase-hibernate4.version>
<liquibase-slf4j.version>1.2.1</liquibase-slf4j.version>
<liquibase.version>3.4.1</liquibase.version>
<mapstruct.version>1.0.0.CR1</mapstruct.version>
<maven-enforcer-plugin.version>1.3.1</maven-enforcer-plugin.version>
<maven-sortpom-plugin.version>2.3.0</maven-sortpom-plugin.version>
<maven.build.timestamp.format>yyyyMMddHHmmss</maven.build.timestamp.format>
<maven.compiler.source>${java.version}</maven.compiler.source>
<maven.compiler.target>${java.version}</maven.compiler.target>
<metrics-spark-reporter.version>1.2</metrics-spark-reporter.version>
<metrics-spring.version>3.1.2</metrics-spring.version>
<!-- Sonar properties -->
<project.testresult.directory>${project.build.directory}/test-results</project.testresult.directory>
<run.addResources>false</run.addResources>
<sonar-maven-plugin.version>2.6</sonar-maven-plugin.version>
<sonar.exclusions>src/main/webapp/assets/**/*.*, src/main/webapp/bower_components/**/*.*, src/main/webapp/dist/**/*.*</sonar.exclusions>
<sonar.jacoco.itReportPath>${project.testresult.directory}/coverage/jacoco/jacoco-it.exec</sonar.jacoco.itReportPath>
<sonar.jacoco.reportPath>${project.testresult.directory}/coverage/jacoco/jacoco.exec</sonar.jacoco.reportPath>
<sonar.java.codeCoveragePlugin>jacoco</sonar.java.codeCoveragePlugin>
<sonar.javascript.jstestdriver.reportsPath>${project.testresult.directory}/karma</sonar.javascript.jstestdriver.reportsPath>
<sonar.javascript.lcov.reportPath>${project.testresult.directory}/coverage/report-lcov/lcov.info</sonar.javascript.lcov.reportPath>
<sonar.sources>${project.basedir}/src/main/</sonar.sources>
<sonar.surefire.reportsPath>${project.testresult.directory}/surefire-reports</sonar.surefire.reportsPath>
<sonar.tests>${project.basedir}/src/test/</sonar.tests>
<spring-security.version>4.0.2.RELEASE</spring-security.version>
<springfox.version>2.0.3</springfox.version>
<usertype-core.version>4.0.0.GA</usertype-core.version>
</properties>
<dependencies>
// dependencies..
</dependencies>
<build>
<resources>
<resource>
<filtering>true</filtering>
<directory>src/main/resources</directory>
<includes>
<include>**/*.xml</include>
</includes>
</resource>
<resource>
<filtering>false</filtering>
<directory>src/main/resources</directory>
<excludes>
<exclude>**/*.xml</exclude>
</excludes>
</resource>
</resources>
<plugins>
<plugin>
<groupId>com.google.code.sortpom</groupId>
<artifactId>maven-sortpom-plugin</artifactId>
<version>${maven-sortpom-plugin.version}</version>
<executions>
<execution>
<phase>verify</phase>
<goals>
<goal>sort</goal>
</goals>
</execution>
</executions>
<configuration>
<sortProperties>true</sortProperties>
<nrOfIndentSpace>4</nrOfIndentSpace>
<sortDependencies>groupId,artifactId</sortDependencies>
<sortPlugins>groupId,artifactId</sortPlugins>
<keepBlankLines>true</keepBlankLines>
<expandEmptyElements>false</expandEmptyElements>
</configuration>
</plugin>
<plugin>
<groupId>io.gatling</groupId>
<artifactId>gatling-maven-plugin</artifactId>
<version>${gatling-maven-plugin.version}</version>
<configuration>
<configFolder>src/test/gatling/conf</configFolder>
<dataFolder>src/test/gatling/data</dataFolder>
<resultsFolder>target/gatling/results</resultsFolder>
<bodiesFolder>src/test/gatling/bodies</bodiesFolder>
<simulationsFolder>src/test/gatling/simulations</simulationsFolder>
<!-- This will force Gatling to ask which simulation to run
This is useful when you have multiple simulations -->
<simulationClass>*</simulationClass>
</configuration>
</plugin>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-eclipse-plugin</artifactId>
<configuration>
<downloadSources>true</downloadSources>
<downloadJavadocs>true</downloadJavadocs>
</configuration>
</plugin>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-enforcer-plugin</artifactId>
<version>${maven-enforcer-plugin.version}</version>
<executions>
<execution>
<id>enforce-versions</id>
<goals>
<goal>enforce</goal>
</goals>
</execution>
</executions>
<configuration>
<rules>
<requireMavenVersion>
<message>You are running an older version of Maven. JHipster requires at least Maven 3.0</message>
<version>[3.0.0,)</version>
</requireMavenVersion>
<requireJavaVersion>
<message>You are running an older version of Java. JHipster requires at least JDK ${java.version}</message>
<version>[${java.version}.0,)</version>
</requireJavaVersion>
</rules>
</configuration>
</plugin>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-surefire-plugin</artifactId>
<configuration>
<argLine>-Xmx256m ${surefireArgLine}</argLine>
<!-- Force alphabetical order to have a reproducible build -->
<runOrder>alphabetical</runOrder>
</configuration>
</plugin>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-war-plugin</artifactId>
<configuration>
<packagingExcludes>WEB-INF/lib/tomcat-*.jar</packagingExcludes>
</configuration>
</plugin>
<plugin>
<groupId>org.bsc.maven</groupId>
<artifactId>maven-processor-plugin</artifactId>
<version>2.2.4</version>
<executions>
<execution>
<id>process</id>
<phase>generate-sources</phase>
<goals>
<goal>process</goal>
</goals>
</execution>
</executions>
<dependencies>
<dependency>
<groupId>org.mapstruct</groupId>
<artifactId>mapstruct-processor</artifactId>
<version>${mapstruct.version}</version>
</dependency>
</dependencies>
<configuration>
<defaultOutputDirectory>${project.build.directory}/generated-sources</defaultOutputDirectory>
<processors>
<processor>org.mapstruct.ap.MappingProcessor</processor>
</processors>
<options>
<mapstruct.suppressGeneratorTimestamp>true</mapstruct.suppressGeneratorTimestamp>
<mapstruct.defaultComponentModel>spring</mapstruct.defaultComponentModel>
</options>
</configuration>
</plugin>
<plugin>
<groupId>org.codehaus.mojo</groupId>
<artifactId>sonar-maven-plugin</artifactId>
<version>${sonar-maven-plugin.version}</version>
</plugin>
<plugin>
<groupId>org.jacoco</groupId>
<artifactId>jacoco-maven-plugin</artifactId>
<version>${jacoco-maven-plugin.version}</version>
<executions>
<execution>
<id>pre-unit-tests</id>
<goals>
<goal>prepare-agent</goal>
</goals>
<configuration>
<!-- Sets the path to the file which contains the execution data. -->
<destFile>${project.testresult.directory}/coverage/jacoco/jacoco.exec</destFile>
<!-- Sets the name of the property containing the settings for JaCoCo runtime agent. -->
<propertyName>surefireArgLine</propertyName>
</configuration>
</execution>
<!-- Ensures that the code coverage report for unit tests is created after unit tests have been run -->
<execution>
<id>post-unit-test</id>
<phase>test</phase>
<goals>
<goal>report</goal>
</goals>
<configuration>
<dataFile>${project.testresult.directory}/coverage/jacoco/jacoco.exec</dataFile>
<outputDirectory>${project.testresult.directory}/coverage/jacoco</outputDirectory>
</configuration>
</execution>
</executions>
</plugin>
<plugin>
<groupId>org.liquibase</groupId>
<artifactId>liquibase-maven-plugin</artifactId>
<version>${liquibase.version}</version>
<dependencies>
<dependency>
<groupId>org.javassist</groupId>
<artifactId>javassist</artifactId>
<version>3.18.2-GA</version>
</dependency>
<dependency>
<groupId>org.liquibase.ext</groupId>
<artifactId>liquibase-hibernate4</artifactId>
<version>${liquibase-hibernate4.version}</version>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-data-jpa</artifactId>
<version>${project.parent.version}</version>
</dependency>
</dependencies>
<configuration>
<changeLogFile>src/main/resources/config/liquibase/master.xml</changeLogFile>
<diffChangeLogFile>src/main/resources/config/liquibase/changelog/${maven.build.timestamp}_changelog.xml</diffChangeLogFile>
<driver />
<url />
<defaultSchemaName />
<username />
<password />
<referenceUrl>hibernate:spring:com.aquevix.demo.domain?dialect=</referenceUrl>
<verbose>true</verbose>
<logging>debug</logging>
</configuration>
</plugin>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
<configuration>
<jvmArguments>-agentlib:jdwp=transport=dt_socket,server=y,suspend=n,address=5005</jvmArguments>
<arguments>
<argument>--spring.profiles.active=dev</argument>
</arguments>
</configuration>
</plugin>
</plugins>
</build>
<profiles>
<profile>
<id>dev</id>
<activation>
<activeByDefault>true</activeByDefault>
</activation>
<properties>
<!-- log configuration -->
<logback.loglevel>DEBUG</logback.loglevel>
</properties>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-tomcat</artifactId>
</dependency>
</dependencies>
</profile>
<profile>
<id>fast</id>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
<configuration>
<arguments>
<argument>--spring.profiles.active=dev,fast</argument>
</arguments>
</configuration>
</plugin>
</plugins>
</build>
<properties>
<!-- log configuration -->
<logback.loglevel>DEBUG</logback.loglevel>
</properties>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-undertow</artifactId>
</dependency>
</dependencies>
</profile>
<profile>
<id>prod</id>
<build>
<plugins>
<plugin>
<groupId>com.github.trecloux</groupId>
<artifactId>yeoman-maven-plugin</artifactId>
<version>0.4</version>
<executions>
<execution>
<id>run-frontend-build</id>
<phase>generate-resources</phase>
<goals>
<goal>build</goal>
</goals>
<configuration>
<buildTool>grunt</buildTool>
<buildArgs>build --force --no-color</buildArgs>
</configuration>
</execution>
</executions>
<configuration>
<yeomanProjectDirectory>${project.basedir}</yeomanProjectDirectory>
</configuration>
</plugin>
<plugin>
<artifactId>maven-clean-plugin</artifactId>
<version>2.5</version>
<configuration>
<filesets>
<fileset> <directory>src/main/webapp/dist</directory>
</fileset>
<fileset>
<directory>.tmp</directory>
</fileset>
<fileset>
<directory>node_modules</directory>
</fileset>
</filesets>
</configuration>
</plugin>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
<configuration>
<arguments>
<argument>--spring.profiles.active=prod</argument>
</arguments>
</configuration>
</plugin>
</plugins>
</build>
<properties>
<!-- log configuration -->
<logback.loglevel>INFO</logback.loglevel>
</properties>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-tomcat</artifactId>
</dependency>
</dependencies>
</profile>
</profiles>
</project>
and chile pom is
智利 pom 是
<?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>
<parent>
<artifactId>demo-jhipster</artifactId>
<groupId>com.aquevix.demo</groupId>
<version>0.0.1-SNAPSHOT</version>
</parent>
<artifactId>JhipsterSubmodule1</artifactId>
</project>
I have googled but not found any solution please help in this regard!
我用谷歌搜索但没有找到任何解决方案，请在这方面提供帮助！
回答by Dennis Hunziker
Do you have a class in your app with a main method like:
您的应用程序中是否有一个带有 main 方法的类，例如：
public static void main(String[] args) {
SpringApplication.run(YourApplication.class, args);
}
Or do you even have multiple classes with main methods, in which case Spring can't figure out which one to use?
或者你甚至有多个带有 main 方法的类，在这种情况下 Spring 无法弄清楚使用哪一个？
回答by Paulo Pedroso
I believe the issue I was having is similar to yours. I have a multi module app using Spring Boot and only one Application.java (with main method).
我相信我遇到的问题与您的相似。我有一个使用 Spring Boot 的多模块应用程序，只有一个 Application.java（使用 main 方法）。
I was struggling with it trying to start it up using Maven and I got the same result as yours (unable to find a suitable main class).
我在尝试使用 Maven 启动它时遇到了困难，但得到了与您相同的结果（无法找到合适的主类）。
I spent several hours trying and changing stuff and after adding the property mainClass to the pom, it couldn't find it.
我花了几个小时尝试和更改东西，在将属性 mainClass 添加到 pom 后，它找不到它。
Then I decided to run the project not from the root project but from the project where the Application class is.
然后我决定不从根项目运行该项目，而是从 Application 类所在的项目运行。
By doing this I was able to start up Spring Boot and everything works like a charm.
通过这样做，我能够启动 Spring Boot，一切都像魅力一样。
Updated
更新
If you want to package the whole thing to be executed with java -jar fileyou can run the command below from the root project:
如果要打包要执行的整个内容，可以java -jar file从根项目运行以下命令：
mvn clean package spring-boot:repackage
Don't forget to add the spring-boot-maven-pluginto your pom.
不要忘记添加spring-boot-maven-plugin到您的 pom.xml 文件中。
回答by Rabin Pantha
You can fix the problem by specifying the location of main as follows:
您可以通过指定 main 的位置来解决问题，如下所示：
mvn spring-boot {com.ishanitech.controller.Application}:run
回答by Marco Nu?ez
The solution is change the pom.xml file
解决方案是更改 pom.xml 文件
from this
由此
<packaging>pom</packaging>
to this
对此
<packaging>war</packaging>
or another value that you need depending of your deployment method.
或您需要的其他值，具体取决于您的部署方法。
回答by Alex
mvn clean spring-boot:start
…will give you the same error.
......会给你同样的错误。
mvn clean package spring-boot:start
…is going to fix the issue by building the artifact before running sprint-boot:start.
...将通过在运行之前构建工件来解决问题sprint-boot:start。
回答by Victor Petit
If you are trying to run a mvn spring-boot:runor just a mvn(as you seem to use JHipster and this is the way they wire it as default goal) in the root of your project, it is normal that if fail according that I think it can only be used in a plain spring boot project.
如果您试图在项目的根目录中运行 amvn spring-boot:run或只是 a mvn（因为您似乎使用 JHipster，这是他们将其作为默认目标的方式），如果失败，我认为它只能是正常的用于普通的弹簧靴项目。
As your parent project seems to have severals Spring-Boot webapps, I guess that each one have their own main() launch class, and that you are just using a parent pom to factorize your poms and be able to package all your applications individually via a single command.
由于您的父项目似乎有几个 Spring-Boot webapps，我猜每个人都有自己的 main() 启动类，并且您只是使用父 pom 来分解您的 poms 并能够通过单独打包所有应用程序一个命令。
So, in that case, just run a mvn package, and not a mvnnor a mvn spring-boot:run.
因此，在这种情况下，只需运行 a mvn package，而不是 amvn或 a mvn spring-boot:run。
回答by orog
Maybe you forgot to specify the main class to start.
也许您忘记指定要启动的主类。
In pom.xml:
在 pom.xml 中：
<properties>
<start-class>com.ishanitech.controller.Application</start-class>
</properties>
回答by Syed Siraj Uddin
Remove the maven build plugin code from the parent pom, which will be similar to the below, the below snippet should be only in the sub module pom where you have main class for spring boot application:
从父 pom 中删除 maven 构建插件代码，这将类似于下面的代码，下面的代码片段应该只在你有 Spring Boot 应用程序主类的子模块 pom 中：
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
</plugins>
</build>
回答by Ram
I have also faced the same problem, but by adding the below line in my pom.xml I resolved the issue for my project:
我也遇到了同样的问题，但是通过在我的 pom.xml 中添加以下行，我解决了我的项目的问题：
<properties>
<start-class>com.hls.om.wp.AgencySearch</start-class>
</properties>
where the AgencySearchclass has the main method for running the spring boot application.
其中AgencySearch该类具有运行 spring boot 应用程序的主要方法。
回答by gnnExplorer
If you are using IntellJ IDEA, maybe you can do it like this:
如果您正在使用IntellJ IDEA，也许您可以这样做：
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
<configuration>
<mainClass>add.your.main.class.application.reference.here</mainClass>
</configuration>
</plugin>
This solved my error.
这解决了我的错误。
