使用Maven的com / fasterxml / jackson / databind / ObjectMapper的NoClassDefFoundError [英] NoClassDefFoundError of com/fasterxml/jackson/databind/ObjectMapper with Maven
问题描述
这是一个与此处类似的问题,但遗憾的是尚未解决。
This is a similar question as the one here, which is unfortunately unresolved yet.
如果你想调试代码,这里是 GitHub repo 。
我得到以下 NoClassDefFoundError
for ObjectMapper
虽然我已将相关依赖项添加到Mave pom.xml
。
I got the following NoClassDefFoundError
for ObjectMapper
though I have added the related dependency to Mave pom.xml
.
Exception in thread "main" java.lang.NoClassDefFoundError: com/fasterxml/jackson/databind/ObjectMapper
at demo.DemoMain.main(DemoMain.java:10)
Caused by: java.lang.ClassNotFoundException: com.fasterxml.jackson.databind.ObjectMapper
at java.net.URLClassLoader.findClass(URLClassLoader.java:381)
at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:331)
at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
... 1 more
这是源代码 DemoMain.java
package demo;
import com.fasterxml.jackson.databind.ObjectMapper;
public class DemoMain {
public static void main(String[] args) {
System.out.println("Start");
ObjectMapper mapper = new ObjectMapper();
System.out.println("End");
}
}
这是我的 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>
<groupId>com.example</groupId>
<artifactId>Demo</artifactId>
<version>1.0-SNAPSHOT</version>
<dependencies>
<dependency>
<groupId>com.fasterxml.jackson.core</groupId>
<artifactId>jackson-annotations</artifactId>
<version>2.8.3</version>
</dependency>
<dependency>
<groupId>com.fasterxml.jackson.core</groupId>
<artifactId>jackson-core</artifactId>
<version>2.8.3</version>
</dependency>
<dependency>
<groupId>com.fasterxml.jackson.core</groupId>
<artifactId>jackson-databind</artifactId>
<version>2.8.3</version>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-jar-plugin</artifactId>
<version>3.0.0</version>
<configuration>
<archive>
<index>true</index>
<manifest>
<addClasspath>true</addClasspath>
<mainClass>demo.DemoMain</mainClass>
</manifest>
</archive>
</configuration>
</plugin>
</plugins>
</build>
我编译并运行应用程序by
I compile and run the app by
mvn clean install
java -jar target/Demo-1.0-SNAPSHOT.jar
提前致谢:)
推荐答案
我回答此处
默认的maven插件不构建带有依赖项的胖jar。
The default maven plugin doesn't build a fat jar with dependencies.
构建一个与其依赖项捆绑在一起的jar,以便我们可以执行它使用 java -jar
,我们可以使用 maven-assembly-plugin ,它使用名称 xxx-jar-with-dependencies.jar
打包jar。
To build a jar bundled with its dependencies so that we can execute it with java -jar
, we can use maven-assembly-plugin, which packages the jar with the name xxx-jar-with-dependencies.jar
.
这是一个示例 pom.xml
<build>
<plugins>
<plugin>
<artifactId>maven-assembly-plugin</artifactId>
<version>3.0.0</version>
<configuration>
<descriptorRefs>
<descriptorRef>jar-with-dependencies</descriptorRef>
</descriptorRefs>
<archive>
<manifest>
<mainClass>com.example.yourMain</mainClass>
</manifest>
</archive>
</configuration>
<executions>
<execution>
<id>make-assembly</id> <!-- this is used for inheritance merges -->
<phase>package</phase> <!-- bind to the packaging phase -->
<goals>
<goal>single</goal>
</goals>
</execution>
</executions>
</plugin>
</plugins>
</build>
现在你应该可以运行你的jar了
Now you should be able to run your jar with
java -jar xxx-jar-with-dependencies.jar
这篇关于使用Maven的com / fasterxml / jackson / databind / ObjectMapper的NoClassDefFoundError的文章就介绍到这了,希望我们推荐的答案对大家有所帮助,也希望大家多多支持IT屋!