kettle读取excel文件输入数据库

请问下用kettle的Api怎么成excel文件中读取数据再插入指定表中？
成数据库中读取数据放入excel文件中这个我写了可以借鉴下？
但哦不知道读再插进去怎么写了
哪位大哥能指点下？。。谢谢！
下面是成数据库中读取数据放入excel文件中的代码：
public class tt
    {
        public static final String[] databasesXML = {
            "<?xml version=\"1.0\" encoding=\"UTF-8\"?>" +
            "<connection>" +
                "<name>source</name>" +
                "<server>localhost</server>" +
                "<type>MYSQL</type>" +
                "<access>Native</access>" +
                "<database>gomai</database>" +
                "<port>3306</port>" +
                "<username>root</username>" +
                "<password>123456</password>" +
                "<servername/>" +
                "<data_tablespace/>" +
                "<index_tablespace/>" +
                "<attributes>" +
                    "<attribute><code>extra_option_mysql.defaultfetchsize</code><attribute>500</attribute></attribute>" +
                    "<attribute><code>extra_option_mysql.usecursorfetch</code><attribute>true</attribute></attribute>" +
                    "<attribute><code>port_number</code><attribute>3306</attribute></attribute>" +
                "</attributes>" +
              "</connection>"  
      };      /**
       * Creates a new Transformation using input parameters such as the tablename to read from.
       * @param  transformationName  转换的名称
       * @param sourceDatabaseName 来源的数据库名
       * @param sourceTableName 表名
       * @param sourceFields 表里的列字段数组
       */
      public static final TransMeta buildCopyTable(String transformationName, String sourceDatabaseName, String sourceTableName, String[] sourceFields) throws KettleException
      {
          
          EnvUtil.environmentInit();
          try
          {
              //创建一个转换
              // Create a new transformation...
              //
              TransMeta transMeta = new TransMeta();
              transMeta.setName(transformationName);
              DatabaseMeta databaseMeta = new DatabaseMeta(databasesXML[0]);
              transMeta.addDatabase(databaseMeta);
              DatabaseMeta sourceDBInfo = transMeta.findDatabase(sourceDatabaseName);
             
              // create the source step...创建输入的步骤，就是读的内容
              //
              String fromstepname = "read from [" + sourceTableName + "]";
              TableInputMeta tii = new TableInputMeta();
              tii.setDatabaseMeta(sourceDBInfo);
              //Const.CR相当于1个回车换行
              String selectSQL = "SELECT "+Const.CR;
              for (int i=0;i<sourceFields.length;i++)
              {
                  if (i>0) selectSQL+=", "; else selectSQL+="  ";
                  selectSQL+=sourceFields[i]+Const.CR;
              }
              selectSQL+="FROM "+sourceTableName;
              //上面的循环是产生查询的SQL语句
              tii.setSQL(selectSQL);
              StepLoader steploader = StepLoader.getInstance();
              //加载
              String fromstepid = steploader.getStepPluginID(tii);
              //根据上面的创建了一个来源步骤
              StepMeta fromstep = new StepMeta(fromstepid, fromstepname, (StepMetaInterface) tii);
              fromstep.setLocation(150, 100);
              fromstep.setDraw(true);
              fromstep.setDescription("Reads information from table [" + sourceTableName + "] on database [" + sourceDBInfo + "]");
              transMeta.addStep(fromstep);              //添加xls输出步骤
              // Add the TableOutputMeta step...
              //
              String tostepname = "write to outputExcel ";
              ExcelOutputMeta toi = new ExcelOutputMeta();              //下面这个设置是全部设置成默认，设成这个，其余的可以都不用设置
              //toi.setDefault();
              
              //这段是手动设置
              toi.setFileName("test");//设置文件名
              toi.setExtension("xls");//扩展名
              toi.setHeaderEnabled(true);//页头
              toi.setSheetname("测试");//sheet工作簿的名字
              int nrfields = 0;
              toi.allocate(nrfields);
              ExcelField outputFields[] = new ExcelField[nrfields];
              for(int i = 0; i < nrfields; i++)
              {
                  outputFields[i] = new ExcelField();
                  outputFields[i].setName("field" + i);
                  outputFields[i].setType("Number");
                  outputFields[i].setFormat("0,000,000.00;-0,000,000.00");
              }
              
              toi.setOutputFields(outputFields);
              //加载这个步骤
              String tostepid = steploader.getStepPluginID(toi);
              //输出步骤
              StepMeta tostep = new StepMeta(tostepid, tostepname, (StepMetaInterface) toi);
              tostep.setLocation(550, 100);
              tostep.setDraw(true);
              tostep.setDescription("写入xls文件");
              transMeta.addStep(tostep);              //为2个步骤创建连接
              // Add a hop between the two steps...
              //
              TransHopMeta hi = new TransHopMeta(fromstep, tostep);
              transMeta.addTransHop(hi);              // 返回这个转换
              return transMeta;
          }
          catch (Exception e)
          {
              throw new KettleException("An unexpected error occurred creating the new transformation", e);
          }
      }      /**
       * 1) create a new transformation  建立一个新的转换（transformation）
       * 2) save the transformation as XML file  把转换（transformation）存储为XML文件
       * 3) Execute the transformation     执行转换（transformation）
       * @param args
       */
      public static void main(String[] args) throws Exception
      {
          EnvUtil.environmentInit();
          // Init the logging...
          LogWriter log = LogWriter.getInstance("TransBuilder.log", true, LogWriter.LOG_LEVEL_DETAILED);
          
          // Load the Kettle steps & plugins 
          StepLoader stloader = StepLoader.getInstance();
        if (!stloader.read())
          {
              log.logError("TransBuilder",  "Error loading Kettle steps & plugins... stopping now!");
              return;
          }
          //要复制的来源数据
          // The parameters we want, optionally this can be 
          String fileName = "NewTrans.xml";
          String transformationName = "Test Transformation";
          //上面XML中配置的connection名字
          String sourceDatabaseName = "source";
          //要找的表名
          String sourceTableName = "user";
          String sourceFields[] = { 
                 "*"  //"*"代表该表中的所有列或字段
              };
          // 产生这个转换
          TransMeta transMeta = tt.buildCopyTable(
                  transformationName,
                  sourceDatabaseName,
                  sourceTableName,
                  sourceFields
                  );
          //将上面生成的转换配置保存为XML文件
          String xml = transMeta.getXML();
          DataOutputStream dos = new DataOutputStream(new FileOutputStream(new File(fileName)));
          dos.write(xml.getBytes("UTF-8"));
          dos.close();
          System.out.println("Saved transformation to file: "+fileName);
          
          //执行转换
          Trans trans = new Trans(transMeta);
          trans.execute(null);
          trans.waitUntilFinished();
        
      }
  }