Question

我无法让maven构建一个可以在我的Ubuntu机器上运行的jar。我的.jar似乎找不到.jar，无论我做什么。

让我感到困惑的是，在堆栈跟踪中显示抛出了斜杠命名空间的错误，就像在java 1.7中一样，然后原因是使用java 1.6命名空间，我不确定这是否与问题。

有关我执行ClassNotFound Exception时<{1}}的原因的任何想法？

我的 pom.xml 具有将依赖项附加到.jar并创建清单的所有正确配置：

.jar

堆栈追踪：

<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>
    <groupId>com.rwanks.pepper</groupId>
    <artifactId>wiki-indexer</artifactId>
    <packaging>jar</packaging>
    <version>1.0-SNAPSHOT</version>
    <name>wiki-indexer</name>
    <url>http://maven.apache.org</url>
    <dependencies>
        <dependency>
            <groupId>commons-logging</groupId>
            <artifactId>commons-logging</artifactId>
            <version>1.2</version>
        </dependency>
        <dependency>
            <groupId>org.apache.lucene</groupId>
            <artifactId>lucene-core</artifactId>
            <version>5.4.0</version>
        </dependency>
        <dependency>
            <groupId>org.apache.lucene</groupId>
            <artifactId>lucene-queryparser</artifactId>
            <version>5.4.0</version>
        </dependency>
        <dependency>
            <groupId>org.apache.lucene</groupId>
            <artifactId>lucene-queries</artifactId>
            <version>5.4.0</version>
        </dependency>
        <dependency>
            <groupId>org.apache.lucene</groupId>
            <artifactId>lucene-analyzers-common</artifactId>
            <version>5.4.0</version>
        </dependency>
        <dependency>
            <groupId>org.apache.lucene</groupId>
            <artifactId>lucene-benchmark</artifactId>
            <version>5.4.0</version>
        </dependency>
        <dependency>
            <groupId>org.apache.solr</groupId>
            <artifactId>solr-solrj</artifactId>
            <version>5.4.0</version>
        </dependency>

        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>3.8.1</version>
            <scope>test</scope>
        </dependency>
    </dependencies>
    <build>
        <plugins>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-jar-plugin</artifactId>
                <version>2.6</version>
                <configuration>
                    <archive>
                        <index>true</index>
                        <manifest>
                            <mainClass>com.rwanks.pepper.WikipediaIndexer</mainClass>
                            <addClasspath>true</addClasspath>
                        </manifest>
                        <manifestEntries>
                            <mode>development</mode>
                            <url>${project.url}</url>
                            <key>value</key>
                        </manifestEntries>
                    </archive>
                </configuration>
            </plugin>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-compiler-plugin</artifactId>
                <version>3.3</version>
                <configuration>
                    <!-- or whatever version you use -->
                    <source>1.7</source>
                    <target>1.7</target>

                </configuration>
            </plugin>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-dependency-plugin</artifactId>
                <executions>
                    <execution>
                        <id>copy-dependencies</id>
                        <phase>process-resources</phase>
                        <goals>
                            <goal>copy-dependencies</goal>
                        </goals>
                        <configuration>
                            <useRepositoryLayout>false</useRepositoryLayout>
                        </configuration>
                    </execution>
                </executions>
            </plugin>

        </plugins>
    </build>
</project>

生成的java -jar target/wiki-indexer-1.0-SNAPSHOT.jar Exception in thread "main" java.lang.NoClassDefFoundError: org/apache/lucene/benchmark/byTask/feeds/NoMoreDataException at java.lang.Class.getDeclaredMethods0(Native Method) at java.lang.Class.privateGetDeclaredMethods(Class.java:2625) at java.lang.Class.getMethod0(Class.java:2866) at java.lang.Class.getMethod(Class.java:1676) at sun.launcher.LauncherHelper.getMainMethod(LauncherHelper.java:494) at sun.launcher.LauncherHelper.checkAndLoadMain(LauncherHelper.java:486) Caused by: java.lang.ClassNotFoundException: org.apache.lucene.benchmark.byTask.feeds.NoMoreDataException at java.net.URLClassLoader$1.run(URLClassLoader.java:366) at java.net.URLClassLoader$1.run(URLClassLoader.java:355) at java.security.AccessController.doPrivileged(Native Method) at java.net.URLClassLoader.findClass(URLClassLoader.java:354) at java.lang.ClassLoader.loadClass(ClassLoader.java:425) at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:308) at java.lang.ClassLoader.loadClass(ClassLoader.java:358) ... 6 more：

MANIFEST.MF

Answer 1

库不在预期的类路径中。

java -jar target/wiki-indexer-1.0-SNAPSHOT.jar在那里加载应用程序jar在子目录target/中。但是清单Class-Path: commons-logging-1.2.jar ...中的类路径表明库应该在当前目录中。

以下应按预期工作

cd target
java -jar wiki-indexer-1.0-SNAPSHOT.jar

修改正如javapapo使用maven-shade-plugin所提到的可以防止此类问题。该插件可以创建一个包含所有依赖项jar中的类的jar文件。

简单的配置可能看起来像。

    <plugins>
        <plugin>
            <artifactId>maven-shade-plugin</artifactId>
            <version>2.4</version>
            <executions>
                <execution>
                    <phase>package</phase>
                    <goals>
                        <goal>shade</goal>
                    </goals>
                </execution>
            </executions>
        </plugin>
    </plugins>

混合Java 1.6和1.7名称空间

1 个答案: