手动注册插件

Question

我正在尝试使用嵌入在 Java 代码中的 PDI 运行转换，但出现关于缺少插件的错误（看起来像是中止步骤）。

我知道我可以使用KETTLE_PLUGIN_BASE_FOLDERS以便 PDI 自动加载它（有效），但为了使我的应用程序更简单，我想使用 Java 手动注册此插件，我该怎么做？

我正在遵循此处提供的示例https://github.com/pentaho/pdi-sdk-plugins/tree/master/kettle-sdk-embedding-samples

2019/08/14 17:03:07 - Could not find on destination DB.0 - ERROR (version 8.2.0.7-719, build 8.2.0.7-719 from 2019-06-24 02.06.35 by buildguy) : Can't run transformation due to plugin missing
2019/08/14 17:03:07 - Could not find on source DB.0 - ERROR (version 8.2.0.7-719, build 8.2.0.7-719 from 2019-06-24 02.06.35 by buildguy) : Can't run transformation due to plugin missing
2019/08/14 17:03:07 - Could not find on destination DB.0 - ERROR (version 8.2.0.7-719, build 8.2.0.7-719 from 2019-06-24 02.06.35 by buildguy) : Error initializing step [Could not find on destination DB]
2019/08/14 17:03:07 - Could not find on source DB.0 - ERROR (version 8.2.0.7-719, build 8.2.0.7-719 from 2019-06-24 02.06.35 by buildguy) : Error initializing step [Could not find on source DB]
2019/08/14 17:03:07 - Could not find on destination DB 2.0 - ERROR (version 8.2.0.7-719, build 8.2.0.7-719 from 2019-06-24 02.06.35 by buildguy) : Can't run transformation due to plugin missing
2019/08/14 17:03:07 - Could not find on destination DB 2.0 - ERROR (version 8.2.0.7-719, build 8.2.0.7-719 from 2019-06-24 02.06.35 by buildguy) : Error initializing step [Could not find on destination DB 2]
2019/08/14 17:03:07 - Abort.0 - ERROR (version 8.2.0.7-719, build 8.2.0.7-719 from 2019-06-24 02.06.35 by buildguy) : Can't run transformation due to plugin missing
2019/08/14 17:03:07 - Abort.0 - ERROR (version 8.2.0.7-719, build 8.2.0.7-719 from 2019-06-24 02.06.35 by buildguy) : Error initializing step [Abort]

Answer 1

要注册一个插件，你必须设置一个系统属性， KETTLE_PLUGIN_CLASSES你初始化KettleEnvironment前，用插件元类的完全限定类名。 该属性可以是您要注册的所有插件的逗号分隔字符串。

这是如何注册插件的示例：

  void initEnv() {
    // Register plugins here
    System.setProperty("KETTLE_PLUGIN_CLASSES","org.pentaho.di.trans.steps.jsoninput.JsonInputMeta");
    try {
      KettleEnvironment.init();
    } catch (KettleException e) {
      e.printStackTrace();
    }
  }

此示例注册JSON Input步骤，这是一个核心插件。 为了让 PDI 成功加载插件，它的 jar 文件必须在类路径上可用。