Question

我在maven项目中创建了两个Java文件，一个是POJO类，另一个是Java主类文件。我想将我的项目制作为可执行的jar文件，并希望使用java -jar命令在外部运行。

请找到我的pom.xml文件

<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>ElasticSearchUtility</groupId>
<artifactId>ElasticSearchUtility</artifactId>
<version>1.0.0-SNAPSHOT</version>
<packaging>jar</packaging>
<dependencies>
    <dependency>
        <groupId>org.elasticsearch</groupId>
        <artifactId>elasticsearch</artifactId>
        <version>6.1.2</version>
    </dependency>
    <dependency>
        <groupId>org.elasticsearch.client</groupId>
        <artifactId>elasticsearch-rest-high-level-client</artifactId>
        <version>6.1.2</version>
    </dependency>
    <dependency>
        <groupId>org.elasticsearch.client</groupId>
        <artifactId>rest</artifactId>
        <version>5.1.2</version>
    </dependency>

</dependencies>

<build>

        <plugins>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-eclipse-plugin</artifactId>
                <version>2.9</version>
                <configuration>
                    <downloadSources>true</downloadSources>
                    <downloadJavadocs>false</downloadJavadocs>
                </configuration>
            </plugin>

            <!-- Set a compiler level -->
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-compiler-plugin</artifactId>
                <version>2.3.2</version>
                <configuration>
                    <source>1.8</source>
                    <target>1.8</target>
                </configuration>
            </plugin>

            <!-- Make this jar executable -->
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-jar-plugin</artifactId>
                <configuration>
                    <excludes>
                        <exclude>**/log4j.properties</exclude>
                    </excludes>
                    <archive>
                        <manifest>
                            <addClasspath>true</addClasspath>
                            <mainClass>com.es.utility.DocumentIndex</mainClass>
                            <classpathPrefix>dependency-jars/</classpathPrefix>
                        </manifest>
                    </archive>
                </configuration>
            </plugin>
            <!-- Copy project dependency -->

            </plugins>
    </build>

使用java -jar命令执行我的jar文件时。出现错误

Error: A JNI error has occurred, please check your installation and try again
Exception in thread "main" java.lang.NoClassDefFoundError: org/elasticsearch/Ela
sticsearchException
        at java.lang.Class.getDeclaredMethods0(Native Method)
        at java.lang.Class.privateGetDeclaredMethods(Unknown Source)
        at java.lang.Class.privateGetMethodRecursive(Unknown Source)
        at java.lang.Class.getMethod0(Unknown Source)
        at java.lang.Class.getMethod(Unknown Source)
        at sun.launcher.LauncherHelper.validateMainClass(Unknown Source)
        at sun.launcher.LauncherHelper.checkAndLoadMain(Unknown Source)
Caused by: java.lang.ClassNotFoundException: org.elasticsearch.ElasticsearchExce
ption
        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)
        ... 7 more

请找到我的项目结构：

Answer 1

创建jar-with-dependencies。

<build>
   <plugins>
      <plugin>
         <artifactId>maven-assembly-plugin</artifactId>
         <configuration>
            <archive>
               <manifest>
                  <mainClass>fully.qualified.MainClass</mainClass>
               </manifest>
            </archive>
            <descriptorRefs>
               <descriptorRef>jar-with-dependencies</descriptorRef>
            </descriptorRefs>
         </configuration>
         <executions>
            <execution>
               <id>make-jar</id>
               <phase>package</phase>
               <goals>
                  <goal>single</goal>
               </goals>
            </execution>
         </executions>
      </plugin>
   </plugins>
</build>

这将创建FatJar或UberJar，其中将包含其中的所有依赖项。

从命令提示符处执行.jar文件时发生了JNI错误

1 个答案: