NoClassDefFoundError: OsgiDefaultCamelContext 使用 Apache ServiceMix

Posted 2023-02-22

【中文标题】NoClassDefFoundError: OsgiDefaultCamelContext 使用 Apache ServiceMix

【英文标题】：NoClassDefFoundError: OsgiDefaultCamelContext using Apache ServiceMix

【发布时间】：2019-08-21 22:17:30

【问题描述】：

我创建了简单的包：

public class Activator implements BundleActivator 

    private CamelContext camelContext;
    private CsvDataFormat csv = new CsvDataFormat();

    public void start(BundleContext bundleContext) throws Exception 
        csv.setDelimiter('|');
        csv.setQuoteDisabled(true);
        camelContext = new OsgiDefaultCamelContext(bundleContext);
        camelContext.addRoutes(new RouteBuilder() 
            @Override
            public void configure() throws Exception 
                from("file://./in/csv?charset=windows-1251")
                        .unmarshal(csv)
                        .process(exchange -> 
                          //do smth
                        );

            
        );
        camelContext.start();
    

    public void stop(BundleContext bundleContext) throws Exception 
        camelContext.stop();
    

我使用Apache ServiceMix。我安装包：

karaf@root>feature:install camel-csv
karaf@root>bundle:install -s mvn:org.apache.camel/camel-core-osgi/2.16.5

但是，当我启动我的包时，我有错误：

Caused by: java.lang.NoClassDefFoundError: org/apache/camel/core/osgi/OsgiDefaultCamelContext
    at ru.camel.csv.Activator.start(Activator.java:19)

但是为什么呢？在karaf 控制台我看到：

222 | Active    |  50 | 2.16.5                             | camel-csv
223 | Active    |  50 | 1.1.0                              | Apache Commons CSV
224 | Resolved  |  80 | 1.0.0.SNAPSHOT                     | csv
228 | Active    |  80 | 2.16.5                             | camel-core-osgi

捆绑camel-core-osgi 包含类OsgiDefaultCamelContext。为什么会出现此错误？

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">
    <parent>
        <artifactId>ru.camel</artifactId>
        <groupId>ru.camel.test</groupId>
        <version>1.0-SNAPSHOT</version>
    </parent>
    <modelVersion>4.0.0</modelVersion>

    <artifactId>csv</artifactId>

    <dependencies>
        <dependency>
            <groupId>org.apache.camel</groupId>
            <artifactId>camel-core-osgi</artifactId>
            <version>2.16.5</version>
        </dependency>
        <dependency>
            <groupId>org.osgi</groupId>
            <artifactId>org.osgi.core</artifactId>
            <version>6.0.0</version>
        </dependency>
        <dependency>
            <groupId>org.apache.camel</groupId>
            <artifactId>camel-csv</artifactId>
            <version>2.16.5</version>
        </dependency>
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <inherited>true</inherited>
                <groupId>org.apache.felix</groupId>
                <artifactId>maven-bundle-plugin</artifactId>
                <executions>
                    <execution>
                        <id>osgi-bundle</id>
                        <goals>
                            <goal>bundle</goal>
                        </goals>
                        <phase>package</phase>
                        <configuration>
                            <instructions>
                                <Bundle-SymbolicName>$project.artifactId</Bundle-SymbolicName>
                                <Bundle-Version>$project.version</Bundle-Version>
                                <Import-Package>org.apache.camel.core.osgi.OsgiDefaultCamelContext</Import-Package>
                                <Bundle-Activator>ru.camel.csv.Activator</Bundle-Activator>
                            </instructions>
                        </configuration>
                    </execution>
                </executions>
            </plugin>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-compiler-plugin</artifactId>
                <configuration>
                    <source>8</source>
                    <target>8</target>
                </configuration>
            </plugin>
        </plugins>
    </build>

</project>

【参考方案1】：

你应该检查你的包的导入。

每个包都必须声明它想要导入的包（类）。您的捆绑包可能没有声明导入 OsgiDefaultCamelContext 所在的包。

导入在您的捆绑包的META-INF/MANIFEST.MF 中定义。根据您的构建工具，此文件可能会在构建期间自动创建。否则，您必须自己编写，尽管我强烈建议您查看在构建期间自动执行此操作的工具。

在您的pom.xml中，将maven-bundle-plugin的Import-Package语句的配置更改为：

<Import-Package>org.apache.camel.core.osgi.*;*</Import-Package>

【讨论】：

这行不通。我添加了我的pom.xml maven-bundle-plugin 和<Import-Package>org.apache.camel.core.osgi.OsgiDefaultCamelContext</Import-Package>。我收到错误：Error starting bundle 224: Unable to resolve csv [224](R 224.1): missing requirement [csv [224](R 224.1)] osgi.wiring.package; (osgi.wiring.package=org.apache.camel.core.osgi.OsgiDefaultCamelContext) Unresolved requirements: [[csv [224](R 224.1)] osgi.wiring.package; (osgi.wiring.package=org.apache.camel.core.osgi.OsgiDefaultCamelContext)]

@All_Safe 该配置称为Import-Package。您添加的是类本身的整个 FQDN，而不是包。我更新了我的答案。看看吧。