使用Mapsforge Mapfile-writer插件与Osmosis生成地图时加载失败求助

使用Mapsforge Mapfile-writer插件搭配Osmosis编译自定义地图时，出现插件加载失败的报错，具体错误信息如下：

Jun 16, 2023 9:09:37 AM org.openstreetmap.osmosis.core.Osmosis run
INFO: Osmosis Version 0.48.3
Jun 16, 2023 9:09:37 AM org.openstreetmap.osmosis.core.Osmosis main
SEVERE: Execution aborted.
org.openstreetmap.osmosis.core.OsmosisRuntimeException: Unable to load plugin class (mapsforge-map-writer-master-20230526.153436-506.jar).
    at org.openstreetmap.osmosis.core.TaskRegistrar.loadPluginClass(TaskRegistrar.java:340)
    at org.openstreetmap.osmosis.core.TaskRegistrar.loadPlugin(TaskRegistrar.java:319)
    at org.openstreetmap.osmosis.core.TaskRegistrar.initialize(TaskRegistrar.java:84)
    at org.openstreetmap.osmosis.core.Osmosis.run(Osmosis.java:81)
    at org.openstreetmap.osmosis.core.Osmosis.main(Osmosis.java:37)
    at java.base/jdk.internal.reflect.DirectMethodHandleAccessor.invoke(DirectMethodHandleAccessor.java:104)
    at java.base/java.lang.reflect.Method.invoke(Method.java:578)
    at org.codehaus.plexus.classworlds.launcher.Launcher.launchStandard(Launcher.java:330)
    at org.codehaus.plexus.classworlds.launcher.Launcher.launch(Launcher.java:238)
    at org.codehaus.plexus.classworlds.launcher.Launcher.mainWithExitCode(Launcher.java:415)
    at org.codehaus.plexus.classworlds.launcher.Launcher.main(Launcher.java:356)
    at org.codehaus.classworlds.Launcher.main(Launcher.java:47)
Caused by: java.lang.ClassNotFoundException: mapsforge-map-writer-master-20230526.153436-506.jar
    at org.codehaus.plexus.classworlds.strategy.SelfFirstStrategy.loadClass(SelfFirstStrategy.java:50)
    at org.codehaus.plexus.classworlds.realm.ClassRealm.unsynchronizedLoadClass(ClassRealm.java:271)
    at org.codehaus.plexus.classworlds.realm.ClassRealm.loadClass(ClassRealm.java:247)
    at org.codehaus.plexus.classworlds.realm.ClassRealm.loadClass(ClassRealm.java:239)
    at org.openstreetmap.osmosis.core.TaskRegistrar.loadPluginClass(TaskRegistrar.java:338)
    ... 11 more

解决方案 #

• 修正插件配置内容：错误核心是Osmosis把jar文件名当成了插件类名加载。打开Osmosis的plugins.conf配置文件，将其中的mapsforge-map-writer-master-20230526.153436-506.jar替换为插件的完整类名org.mapsforge.map.writer.osmosis.MapFileWriterPlugin。

• 确认插件jar放置路径：确保插件jar文件放在Osmosis安装目录下的plugins文件夹中；如果使用自定义路径，启动Osmosis时需通过参数指定插件目录，示例命令：

  osmosis -Dplugin.dir=/your/custom/plugin/path [其他编译参数]
  

• 匹配版本兼容性：你当前使用的是Osmosis 0.48.3，建议下载与该版本兼容的Mapsforge Mapfile-writer稳定版插件，避免使用快照版（如你当前的master快照包），减少版本不兼容导致的类加载问题。

• 检查Java环境：确保使用的Java版本符合要求，Osmosis 0.48.3兼容Java 8及以上版本，避免高版本Java带来的兼容性冲突。

内容的提问来源于stack exchange，提问作者saad