-Dfile.encoding=UTF-8,-DKETTLE_PLUGIN_CLASSES=org.pentaho.di.sdk.samples.steps.job.JobStepMeta要怎么拼接

要拼接这个字符串，可以使用加号（+）操作符连接字符串，例如：

String str = "-Dfile.encoding=UTF-8," + "-DKETTLE_PLUGIN_CLASSES=org.pentaho.di.sdk.samples.steps.job.JobStepMeta";

或者使用StringBuilder类来构建字符串，例如：

StringBuilder sb = new StringBuilder();
sb.append("-Dfile.encoding=UTF-8,");
sb.append("-DKETTLE_PLUGIN_CLASSES=org.pentaho.di.sdk.samples.steps.job.JobStepMeta");
String result = sb.toString();