ETL工具kettle与JAVA结合使用程序生成转换

    最近公司领导安排打造ETL支撑平台，使用ETL工具kettle6.0对数据库的数据进行清洗，使用工具spoon来使用一些图形化的操作比较简单，抽空研究了下用使用kettle的一些jar包，把kettle结合到java（web项目一样）程序中。留作一个记录，以后备用查看。

    先看看网站上下了很多资料看http://infocenter.pentaho.com/help/index.jsp?topic=%2Fcat_dev_guides%2Ftop_dev_guides.html（主要看Developer Guides/Embedding and Extending Pentaho Data Integration/...）

    下载kettle的api和源码看看，也可以帮你解决不少问题的。

    下面是我自己写的一个生成.ktr文件的代码。

    (添加的jar包，我也没有太多的注意，看例子加入（有些可能没有必要，可以尝试的去掉一些测试下）的：

avalon-framework-4.1.3.jar

commons-collections-3.2.jar

commons-io-1.4.jar

commons-lang-2.4.jar

commons-logging-1.1.jar

commons-vfs-20091118-pentaho.jar

kettle-core-4.4.0-GA.jar

kettle-db-4.4.0-GA.jar

kettle-engine-4.4.0-GA.jar

log4j-1.2.12.jar

logkit-1.0.1.jar

servlet-api-2.3.jar）

package com.jeefw.test.testKettle;
import java.io.File;

import org.apache.commons.io.FileUtils;
import org.pentaho.di.core.KettleEnvironment;
import org.pentaho.di.core.database.DatabaseMeta;
import org.pentaho.di.core.exception.KettleException;
import org.pentaho.di.core.plugins.PluginRegistry;
import org.pentaho.di.core.plugins.StepPluginType;
import org.pentaho.di.core.xml.XMLHandler;
import org.pentaho.di.repository.kdr.KettleDatabaseRepository;
import org.pentaho.di.trans.Trans;
import org.pentaho.di.trans.TransHopMeta;
import org.pentaho.di.trans.TransMeta;
import org.pentaho.di.trans.step.StepMeta;
import org.pentaho.di.trans.steps.insertupdate.InsertUpdateMeta;
import org.pentaho.di.trans.steps.tableinput.TableInputMeta;
import org.w3c.dom.Document;

import com.dareway.framework.util.KettleUtil;
public class TransDemo {
public static TransDemo transDemo;

/**
* 两个库中的表名
*/
public static String bjdt_tablename = "wr";
public static String kettle_tablename = "wr";

/**
* 数据库连接信息,适用于DatabaseMeta其中 一个构造器DatabaseMeta(String xml)
*/
public static final String[] databasesXML = {
"<?xml version=\"1.0\" encoding=\"UTF-8\"?>" +
"<connection>" +
"<name>bjdt</name>" +
"<server>127.0.0.1</server>" +
"<type>Oracle</type>" +
"<access>Native</access>" +
"<database>orcl</database>" +
"<port>1521</port>" +
"<username>scott</username>" +
"<password>tiger</password>" +

"<attributes>"+
"<attribute><code>EXTRA_OPTION_ORACLE.characterEncoding</code><attribute>utf-8</attribute></attribute>"+
"</attributes>"+

"</connection>",
"<?xml version=\"1.0\" encoding=\"UTF-8\"?>" +
"<connection>" +
"<name>kettle</name>" +
"<server>127.0.0.1</server>" +
"<type>Mysql</type>" +
"<access>Native</access>" +
"<database>jeefw</database>" +
"<port>3306</port>" +
"<username>root</username>" +
"<password>root</password>" +

"<attributes>"+
"<attribute><code>EXTRA_OPTION_MYSQL.characterEncoding</code><attribute>utf-8</attribute></attribute>"+
"</attributes>"+

"</connection>"
};
/**
* @param args
*/
public static void main(String[] args) {
try {
KettleEnvironment.init();
transDemo = new TransDemo();
TransMeta transMeta = transDemo.generateMyOwnTrans();
String transXml = transMeta.getXML();

String transName = "update_insert_Trans.ktr";
File file = new File(transName);
FileUtils.writeStringToFile(file, transXml, "UTF-8");
// System.out.println("transXml:"+transXml);
// System.out.println(databasesXML.length+"\n"+databasesXML[0]+"\n"+databasesXML[1]);

String xmls = "<?xml version=\"1.0\" encoding=\"UTF-8\"?> \n" + transMeta.getXML().toString();
Document doc = XMLHandler.loadXMLString(xmls);

KettleDatabaseRepository repository = KettleUtil.getRepository();

TransMeta tm = new TransMeta();
tm.loadXML(doc.getDocumentElement(), repository, false);
tm.setRepositoryDirectory(repository.findDirectory("/"));

Trans trans=new Trans(tm);
trans.execute(null);
//trans.setParameterValue("characterEncoding", "utf-8");

} catch (Exception e) {
e.printStackTrace();
return;
}

}

/**
* 生成一个转化,把一个数据库中的数据转移到另一个数据库中,只有两个步骤,第一个是表输入,第二个是表插入与更新操作
* @return
* @throws KettleException
*/
public TransMeta generateMyOwnTrans() throws KettleException{

System.out.println("************start to generate my own transformation***********");

TransMeta transMeta = new TransMeta();

//设置转化的名称
transMeta.setName("insert_update");

//添加转换的数据库连接
for (int i=0;i<databasesXML.length;i++){
DatabaseMeta databaseMeta = new DatabaseMeta(databasesXML[i]);

transMeta.addDatabase(databaseMeta);
}

//registry是给每个步骤生成一个标识Id用
PluginRegistry registry = PluginRegistry.getInstance();

//******************************************************************

//第一个表输入步骤(TableInputMeta)
TableInputMeta tableInput = new TableInputMeta();
String tableInputPluginId = registry.getPluginId(StepPluginType.class, tableInput);
//给表输入添加一个DatabaseMeta连接数据库
DatabaseMeta database_bjdt = transMeta.findDatabase("bjdt");

// java.util.Properties p = new java.util.Properties();
// p.setProperty("attribute", value)
//
// database_bjdt.setAttributes(attributes);

tableInput.setDatabaseMeta(database_bjdt);
String select_sql = "SELECT * FROM "+bjdt_tablename;
tableInput.setSQL(select_sql);

//添加TableInputMeta到转换中
StepMeta tableInputMetaStep = new StepMeta(tableInputPluginId,"table input",tableInput);

//给步骤添加在spoon工具中的显示位置
tableInputMetaStep.setDraw(true);
tableInputMetaStep.setLocation(100, 100);

transMeta.addStep(tableInputMetaStep);
//******************************************************************

//******************************************************************
//第二个步骤插入与更新
InsertUpdateMeta insertUpdateMeta = new InsertUpdateMeta();
String insertUpdateMetaPluginId = registry.getPluginId(StepPluginType.class,insertUpdateMeta);
//添加数据库连接
DatabaseMeta database_kettle = transMeta.findDatabase("kettle");

insertUpdateMeta.setDatabaseMeta(database_kettle);
//设置操作的表
insertUpdateMeta.setTableName(kettle_tablename);

//设置用来查询的关键字
insertUpdateMeta.setKeyLookup(new String[]{"ID"});
insertUpdateMeta.setKeyStream(new String[]{"ID"});
insertUpdateMeta.setKeyStream2(new String[]{""});//一定要加上
insertUpdateMeta.setKeyCondition(new String[]{"="});

//设置要更新的字段
String[] updatelookup = {"ID","dept_no","dept_name","dept_sex","dept_addr"} ;
String [] updateStream = {"id","dept_no","dept_name","dept_sex","dept_addr"};
Boolean[] updateOrNot = {false,true,true,true,true,true,true};
insertUpdateMeta.setUpdateLookup(updatelookup);
insertUpdateMeta.setUpdateStream(updateStream);
insertUpdateMeta.setUpdate(updateOrNot);
String[] lookup = insertUpdateMeta.getUpdateLookup();
//System.out.println("******:"+lookup[1]);
//System.out.println("insertUpdateMetaXMl:"+insertUpdateMeta.getXML());
//添加步骤到转换中
StepMeta insertUpdateStep = new StepMeta(insertUpdateMetaPluginId,"insert_update",insertUpdateMeta);
insertUpdateStep.setDraw(true);
insertUpdateStep.setLocation(250,100);
transMeta.addStep(insertUpdateStep);

//******************************************************************

a6c1
//******************************************************************
//添加hop把两个步骤关联起来
transMeta.addTransHop(new TransHopMeta(tableInputMetaStep, insertUpdateStep));
System.out.println("***********the end************");
return transMeta;
}
}