Question

整个晚上，我一直在浏览各种帖子，似乎找不到适合我的解决方案。我把所有的东西都准备好了，建立了我的jar，运行了'java -jar myProject.jar'并收到了这个消息：

Error: Could not find or load main class com.myProject.MyProject
Caused by: java.lang.ClassNotFoundException: com.myProject.MyProject

我已经提取了jar文件，并且在那里有class文件。我对Java还是一个相对较新的人，所以我不确定这是否相关，但是如果在jar文件中单击“编辑MyProject.class”，其内容如下所示：

Êþº¾

除此之外，我不确定其他地方。我的源目录设置正确，“ com”包位于jar文件的第一层。

可能还值得注意的是，这是使用Maven的Spring-boot应用程序。

编辑：

在上面，我将包编辑为com.myProject.MyProject（为简单起见），但其中还有另一层，体现在下面的代码“ com.myProject.myProject.MyProject”中。抱歉，这很令人困惑：/

MyProject.java：

package com.myProject.myProject;

// imports excluded for brevity

@SpringBootApplication
public class MyProject {

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

// Fix the CORS errors
@Bean
public FilterRegistrationBean simpleCorsFilter() {
    UrlBasedCorsConfigurationSource source = new UrlBasedCorsConfigurationSource();
    CorsConfiguration config = new CorsConfiguration();
    config.setAllowCredentials(true);
    // *** URL below needs to match the Vue client URL and port ***
    config.setAllowedOrigins(Collections.singletonList("http://localhost:8080"));
    config.setAllowedMethods(Collections.singletonList("*"));
    config.setAllowedHeaders(Collections.singletonList("*"));
    source.registerCorsConfiguration("/**", config);
    FilterRegistrationBean bean = new FilterRegistrationBean<>(new CorsFilter(source));
    bean.setOrder(Ordered.HIGHEST_PRECEDENCE);
    return bean;
}
}

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>
<parent>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-parent</artifactId>
    <version>2.1.1.RELEASE</version>
    <relativePath/> <!-- lookup parent from repository -->
</parent>
<groupId>com.myProject</groupId>
<artifactId>myProject</artifactId>
<version>0.0.1-SNAPSHOT</version>
<name>myProject</name>
<description>My Project</description>

<properties>
    <start-class>com.myProject.myProject.MyProject</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-data-rest</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.springframework.session</groupId>
        <artifactId>spring-session-core</artifactId>
    </dependency>

    <dependency>
        <groupId>mysql</groupId>
        <artifactId>mysql-connector-java</artifactId>
        <scope>runtime</scope>
    </dependency>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-test</artifactId>
        <scope>test</scope>
    </dependency>
    <dependency>
        <groupId>org.springframework.security</groupId>
        <artifactId>spring-security-test</artifactId>
        <scope>test</scope>
    </dependency>

    <dependency>
        <groupId>org.projectlombok</groupId>
        <artifactId>lombok</artifactId>
        <version>1.18.4</version>
        <scope>provided</scope>
    </dependency>

    <dependency>
        <groupId>org.springframework.security.oauth</groupId>
        <artifactId>spring-security-oauth2</artifactId>
        <version>2.3.4.RELEASE</version>
    </dependency>

    <dependency>
        <groupId>org.springframework.security</groupId>
        <artifactId>spring-security-acl</artifactId>
        <version>5.1.3.RELEASE</version>
    </dependency>

    <dependency>
        <groupId>org.springframework.security</groupId>
        <artifactId>spring-security-jwt</artifactId>
        <version>1.0.8.RELEASE</version>
    </dependency>

    <dependency>
        <groupId>com.sun.xml.bind</groupId>
        <artifactId>jaxb-impl</artifactId>
        <version>2.2.11</version>
    </dependency>

    <dependency>
        <groupId>com.sun.xml.bind</groupId>
        <artifactId>jaxb-core</artifactId>
        <version>2.2.11</version>
    </dependency>

</dependencies>

</project>

MANIFEST.MF：

Manifest-Version: 1.0
Main-Class: com.myProject.myProject.MyProject
Start-Class: com.myProject.myProject.MyProject

更新：我还尝试使用mvn install创建jar，尝试运行该jar文件时，生成的jar文件会引发相同的错误。

Answer 1

Spring Boot要求您在pom.xml中的属性的<start-class>标记中指定主类

<properties>
<!-- The main class to start by executing "java -jar"-->
<start-class>com.myProject.MyProject</start-class>
</properties>

编辑

根据pom.xml文件的包结构应如下所示

如果您确定应用程序只有一个主入口点。然后尝试将启动程序pom.xml更新为以下基本依赖关系，并在执行生成的jar之前执行mvn clean install。

    <?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>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.1.3.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <groupId>com.myProject</groupId>
    <artifactId>myProject</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>myproject</name>
    <description>My Project</description>

    <properties>
        <java.version>1.8</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>
    </dependencies>

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

</project>

Intelli-J的构建jar无法执行

1 个答案: