已经有一篇文章，经测试是可以的，不过好像不太正宗，可以到参考原文。

官方的连接repository的示例代码如下：

KettleEnvironment.init();RepositoriesMeta repositoriesMeta = new RepositoriesMeta();repositoriesMeta.readData();RepositoryMeta repositoryMeta = repositoriesMeta.findRepository( repositoryName );PluginRegistry registry = PluginRegistry.getInstance();Repository repository = registry.loadClass(       RepositoryPluginType.class,       repositoryMeta,       Repository.class  );repository.init(repositoryMeta);repository.connect(username, password);RepositoryDirectoryInterface tree=repository.loadRepositoryDirectoryTree();TransMeta transMeta=repository.loadTransformation("first",tree,listener,false,null);Trans Trans = new Trans(transMeta);trans.execute(arguments);trans.waitUntilFinished();Result result = trans.getResult();//这样就获取到了数据库形式的资源库，可以加载转换和job并运行了。repositoryName就是在spoon中创建的资源库名称，这里会读取用户目录下.kettle/repositories.xml文件，并根据repositoryName获取资源库的具体信息。

添加 parameters, variables 和 arguments 

try {  for (String key : parameterMap.keySet()) {    transMeta.setParameterValue(key, parameterMap.get(key));  }  for (String key : variableMap.keySet()) {    transMeta.setVariable(key, variableMap.get(key));  }} catch (UnknownParamException e) {    error(e.getMessage());}transMeta.setArguments(arguments);

获取转换或job中某一步骤的输入和输出的数据，需要添加一个RowListener（RowAdapter）：

Trans Trans = new Trans(transMeta);// prepare the execution of the transformation (instead of simply execute)trans.prepareExecution(arguments);// Find a step thread (ready to run but not yet started)// You can also use method Trans.findBaseStep which gives back a list of all the step copies//先获取感兴趣的那个步骤，也可以使用Trans.findBaseStep方法获取所有步骤的一个副本。StepInterface step = trans.findRunThread("Your Step Name");// Attach a row listener to a step copystep.addRowListener(new RowAdapter() {    public void rowReadEvent(RowMetaInterface rowMeta, Object[] row) throws KettleStepException {       // Here you get the rows as they are read by the step          //该步骤读取的数据，即上一步骤传入的数据       }    public void rowWrittenEvent(RowMetaInterface rowMeta, Object[] row) throws KettleStepException {       // Here you get the rows as they are written by the step        //该步骤输出的数据，即处理后传给下一步骤的数据    }  });// Now start the transformation threads...trans.startThreads();// If you want to wait until the transformation is finished...trans.waitUntilFinished(); // If you want to know about the execution result.Result result = trans.getResult();

还可以手动向转换中添加数据，不需要从文件或数据库中读取，详情。

Options

Example

Here is some information on how to do it:

• You can ask a Trans object for a RowProducer object
• Also see the unit test case: 

Use this type of code:

Trans trans = new Trans(... TransMeta ...);trans.prepareExecution(args);RowProcuder rp = trans.addRowProducer(String stepname, int stepCopy);

After that you start the threads in the transformation. Then you can inject the rows while the transformation is running:

trans.startThreads();...rp.putRow(some row you need to inject);...

You can also specify the rows you are expecting to be injected. This makes it easier to build transformations because you have the meta-data at design time.

嵌入到其它项目中使用，参考

未完待续，如有更好的相关博文，可以留言贴地址，继续参考丰富一下。