Intellij Maven java.lang.NoClassDefFoundError with

Question

我正在尝试运行一个非常简单的程序，它在运行时需要一个类：

import com.fasterxml.jackson.dataformat.yaml.YAMLFactory;

public class App {

    public static void main(String[] args) {

        YAMLFactory yf =  new YAMLFactory();

    }

}

它正在编译，但我得到了

Exception in thread "main" java.lang.NoClassDefFoundError: com/fasterxml/jackson/dataformat/yaml/YAMLFactory

    at App.main(App.java:6)

Caused by: java.lang.ClassNotFoundException: com.fasterxml.jackson.dataformat.yaml.YAMLFactory

运行罐子。

我同时使用maven-assembly-plugin并maven-shade-plugin包含对 jar 的依赖项，它们都不适合我。

我的 pom.xml：

Answer 1

您可以像这样配置您的 Maven 程序集插件（您不需要其他插件）。这会将所有 .class 文件放入您的 jar 中。mvn clean install生成你的jar，然后java -jar target/yourJar-jar-with-dependencies.jar执行。有关更多详细信息，请查看http://maven.apache.org/plugins/maven-assembly-plugin/我给你留了一个改进的 maven 3 的 pom 文件（实际上问题出在这个版本的 maven 上不可用的 pluginManagement 标签）。您也不需要 maven jar 插件。请找到这两个模式以获取完整的详细信息https://maven.apache.org/xsd/maven-v3_0_0.xsdhttp://maven.apache.org/xsd/maven-4.0.0.xsd<?xml version="1.0" encoding="UTF-8"?><project xmlns="http://maven.apache.org/POM/4.0.0"&nbsp; &nbsp; &nbsp; &nbsp; &nbsp;xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"&nbsp; &nbsp; &nbsp; &nbsp; &nbsp;xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">&nbsp; &nbsp; <modelVersion>4.0.0</modelVersion>&nbsp; &nbsp; <groupId>App</groupId>&nbsp; &nbsp; <artifactId>App</artifactId>&nbsp; &nbsp; <version>1.0-SNAPSHOT</version>&nbsp; &nbsp; <properties>&nbsp; &nbsp; &nbsp; &nbsp; <maven.compiler.source>1.8</maven.compiler.source>&nbsp; &nbsp; &nbsp; &nbsp; <maven.compiler.target>1.8</maven.compiler.target>&nbsp; &nbsp; </properties>&nbsp; &nbsp; <dependencies>&nbsp; &nbsp; &nbsp; &nbsp; <dependency>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <groupId>org.json</groupId>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <artifactId>json</artifactId>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <version>20180813</version>&nbsp; &nbsp; &nbsp; &nbsp; </dependency>&nbsp; &nbsp; &nbsp; &nbsp; <dependency>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <groupId>com.fasterxml.jackson.core</groupId>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <artifactId>jackson-core</artifactId>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <version>2.9.8</version>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <scope>compile</scope>&nbsp; &nbsp; &nbsp; &nbsp; </dependency>&nbsp; &nbsp; &nbsp; &nbsp; <dependency>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <groupId>com.fasterxml.jackson.core</groupId>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <artifactId>jackson-annotations</artifactId>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <version>2.9.8</version>&nbsp; &nbsp; &nbsp; &nbsp; </dependency>&nbsp; &nbsp; &nbsp; &nbsp; <dependency>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <groupId>com.fasterxml.jackson.core</groupId>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <artifactId>jackson-databind</artifactId>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <version>2.9.8</version>&nbsp; &nbsp; &nbsp; &nbsp; </dependency>&nbsp; &nbsp; &nbsp; &nbsp; <!-- https://mvnrepository.com/artifact/com.fasterxml.jackson.dataformat/jackson-dataformat-yaml -->&nbsp; &nbsp; &nbsp; &nbsp; <!-- https://mvnrepository.com/artifact/com.fasterxml.jackson.dataformat/jackson-dataformat-yaml -->&nbsp; &nbsp; &nbsp; &nbsp; <dependency>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <groupId>com.fasterxml.jackson.dataformat</groupId>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <artifactId>jackson-dataformat-yaml</artifactId>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <version>2.9.8</version>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <scope>compile</scope>&nbsp; &nbsp; &nbsp; &nbsp; </dependency>&nbsp; &nbsp; </dependencies>&nbsp; &nbsp; <build>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <plugins>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <plugin>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <artifactId>maven-assembly-plugin</artifactId>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <version>3.1.0</version>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <configuration>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <finalName>your-jar-1.0</finalName>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <archive>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <manifest>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <addClasspath>true</addClasspath>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <mainClass>App</mainClass>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; </manifest>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; </archive>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <descriptorRefs>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <descriptorRef>jar-with-dependencies</descriptorRef>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; </descriptorRefs>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; </configuration>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <executions>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <execution>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <id>make-assembly</id>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <phase>package</phase>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <goals>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <goal>single</goal>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; </goals>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; </execution>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; </executions>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; </plugin>&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <!-- Compile in Java 1.8 -->&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <!--<plugin>-->&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <!--&lt;!&ndash; Build an executable JAR &ndash;&gt;-->&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <!--<groupId>org.apache.maven.plugins</groupId>-->&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <!--<artifactId>maven-jar-plugin</artifactId>&nbsp; &nbsp; &nbsp; &nbsp;-->&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <!--<version>3.1.0</version>-->&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <!--<configuration>-->&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <!--<archive>-->&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <!--<manifest>-->&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <!--<mainClass>App</mainClass>-->&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <!--<addClasspath>true</addClasspath>-->&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <!--</manifest>-->&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <!--</archive>-->&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <!--</configuration>-->&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; <!--</plugin>-->&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; </plugins>&nbsp; &nbsp; </build></project>