java - FrameworkUtil.getBundle 总是返回 NULL

Question

我正在尝试使用 OSGi 框架安装捆绑软件。下面是我尝试获取 bundleContext 的代码。

在下面的代码中，每次 FrameworkUtil.getBundle 这行都会返回 null。

下面是我的应用程序代码-

    public App() {

        String basePath = "C:\\Tool\\LocalStorage";

        final BundleContext bundleContext = FrameworkUtil.getBundle(this.getClass()).getBundleContext();

                 // install various bundles-

        final Bundle bundle = bundleContext.installBundle(localFilenameOfBundles);
        bundle.start();     

        }

我调试代码的时候发现在FrameworkUtil类的getBundle方法中——

public static Bundle getBundle(final Class< ? > classFromBundle) {
        // We use doPriv since the caller may not have permission
        // to call getClassLoader.
        Object cl = AccessController
                .doPrivileged(new PrivilegedAction<Object>() {
            public Object run() {
                return classFromBundle.getClassLoader();
            }
        });

        if (cl instanceof BundleReference) {
            return ((BundleReference) cl).getBundle();
        }
        return null;
    }

cl 不是 BundleReference 的实例，这就是它总是返回 NULL 的原因。当我检查 cl 时，我发现了这样的东西-

sun.misc.Launcher$AppClassLoader@69956995 我认为这不是 BundleReference 的实例？我需要这个 org.eclipse.osgi.internal.baseadaptor.DefaultClassLoader

下面是我的 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/maven-v4_0_0.xsd">

    <parent>
        <groupId>com.host.Stream</groupId>
        <artifactId>Stream-parent</artifactId>
        <version>2.0.0-SNAPSHOT</version>
        <relativePath>../Build/superpom</relativePath>
    </parent>

    <modelVersion>4.0.0</modelVersion>
    <groupId>com.host.personallization.eye</groupId>
    <artifactId>eye</artifactId>
    <packaging>jar</packaging>
    <name>eye</name>


    <build>
        <plugins>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-eclipse-plugin</artifactId>
                <configuration>
                    <downloadSources>true</downloadSources>
                    <downloadJavadocs>false</downloadJavadocs>
                </configuration>
            </plugin>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-jar-plugin</artifactId>
                <configuration>                         <!-- Configuration of the archiver -->
                    <archive>                       <!-- Manifest specific configuration -->
                        <manifest>                  <!-- Classpath is added to the manifest of the created jar file. -->
                            <addClasspath>true</addClasspath>   <!-- Configures the classpath prefix. This configuration option is used to 
                                specify that all needed libraries are found under lib/ directory. -->
                            <classpathPrefix>lib/</classpathPrefix> <!-- Specifies the main class of the application -->
                            <mainClass>com.host.Stream.eye.eyeApp</mainClass>
                        </manifest>
                    </archive>
                    <includes>
                        <include>**/*.xml</include>
                        <include>**/*.class</include>
                    </includes>
                    <finalName>${project.artifactId}</finalName>
                </configuration>
            </plugin>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-dependency-plugin</artifactId>
                <version>2.6</version>
                <executions>
                    <execution>
                        <id>unpack</id>
                        <phase>prepare-package</phase>
                        <goals>
                            <goal>unpack</goal>
                        </goals>
                        <configuration>
                            <artifactItems>
                                <artifactItem>
                                    <groupId>com.host.raptor</groupId>
                                    <artifactId>ConfigWeb</artifactId>
                                    <type>war</type>
                                    <overWrite>true</overWrite>
                                    <outputDirectory>buildsrc/StreamConf</outputDirectory>
                                    <includes>**</includes>
                                </artifactItem>
                            </artifactItems>
                        </configuration>
                    </execution>
                </executions>
            </plugin>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-resources-plugin</artifactId>
                <executions>
                    <execution>
                        <phase>prepare-package</phase>
                        <goals>
                            <goal>copy-resources</goal>
                        </goals>
                    </execution>
                </executions>
                <configuration>
                    <outputDirectory>target/config/StreamConf</outputDirectory>
                    <resources>
                        <resource>
                            <directory>buildsrc/StreamConf</directory>
                            <includes>
                                <include>**</include>
                            </includes>
                        </resource>
                    </resources>
                </configuration>
            </plugin>
            <plugin>
                <groupId>com.google.code.maven-replacer-plugin</groupId>
                <artifactId>maven-replacer-plugin</artifactId>
                <executions>
                    <execution>
                        <phase>prepare-package</phase>
                        <goals>
                            <goal>replace</goal>
                        </goals>
                    </execution>
                </executions>
                <configuration>
                    <file>target/config/StreamConf/eyewiring.xml</file>
                    <regex>false</regex>
                    <replacements>
                        <replacement>
                            <token>dynamic_build_label_place_holder</token>
                            <value>${project.artifactId}-${project.version}-${buildNumber}</value>
                        </replacement>

                    </replacements>
                </configuration>
            </plugin>
            <plugin>
                <artifactId>maven-assembly-plugin</artifactId>
                <executions>
                    <execution>
                        <phase>package</phase>
                        <id>assembly</id>
                        <goals>
                            <goal>single</goal>
                        </goals>
                        <configuration>
                            <descriptors>
                                <descriptor>assembly.xml</descriptor>
                            </descriptors>
                            <finalName>${project.artifactId}-${project.version}-${buildNumber}</finalName>
                        </configuration>
                    </execution>
                </executions>
            </plugin>
            <plugin>
                <groupId>org.codehaus.mojo</groupId>
                <artifactId>findbugs-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>
    <dependencies>

        <dependency>
            <groupId>com.host.Stream</groupId>
            <artifactId>Streamframework</artifactId>
            <version>2.0.0-SNAPSHOT</version>
        </dependency>

        <dependency>
            <groupId>com.host.external</groupId>
            <artifactId>ucirrus-db</artifactId>
            <version>0.7.3</version>
        </dependency>

        <dependency>
            <groupId>com.host.Stream</groupId>
            <artifactId>Streamcore</artifactId>
            <version>2.0.0-SNAPSHOT</version>
        </dependency>
        <dependency>
            <groupId>org.osgi</groupId>
            <artifactId>org.osgi.core</artifactId>
            <version>4.3.0</version>
        </dependency>
        <dependency>
            <groupId>org.springframework.osgi</groupId>
            <artifactId>spring-osgi-core</artifactId>
            <version>1.2.1</version>
        </dependency>
        <dependency>
            <groupId>org.springframework.osgi</groupId>
            <artifactId>spring-osgi-extender</artifactId>
            <version>1.2.1</version>
        </dependency>

        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-context</artifactId>
            <version>3.2.3.RELEASE</version>
        </dependency>

        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-aop</artifactId>
            <version>3.2.3.RELEASE</version>
        </dependency>


        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-beans</artifactId>
            <version>3.2.3.RELEASE</version>
        </dependency>


        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-core</artifactId>
            <version>3.2.3.RELEASE</version>
        </dependency>

        <dependency>
            <groupId>org.springframework.osgi</groupId>
            <artifactId>spring-osgi-io</artifactId>
            <version>1.2.1</version>
        </dependency>
    </dependencies>
</project>

我在这里遗漏了什么吗？我想我面临的问题是 OSGi 类加载。因为我认为——每个 Bundle 都有自己的类加载器，一个 DefaultClassLoader。但在我的情况下，类加载器是不同的，我不确定如何解决这个问题？

Answer 1

您的类不是由 OSGi 包类加载器加载的。事实上，它是由 AppClassLoader 加载的，它是 JVM 中的默认类加载器，用于在主应用程序类路径上加载类——即 -classpath 中列出的 jar 和目录命令行变量。

您真的创建了 OSGi 包吗？您是否启动了 OSGi 框架并将您的包安装到其中？因为看起来您只是在此处运行纯 Java。