DZone Snippets: java code

Using JavaScript for ETL transformations

ejboy (Fyodor Kupolov) — Sun, 16 Mar 2008 12:01:32 GMT

Scriptella provides a simple way to perform various transformations in JavaScript (or other scripting language which have a corresponding driver).
Our example transformation consists of 3 steps:
1) Select rows from source table.
2) Transform a column value from number to text
3) Insert a transformed value into a destination table.







    

     

     



    



    

        SELECT * FROM Table_In

        

        

         

                           if (Error_Code < 5) {

                    Error_Code='WARNING'; //Set a transformed value

               } else {

                    Error_Code='ERROR'; //Set a transformed value

               }

               query.next(); //Don't forget to trigger nested scripts execution

            ]]>

How to execute Scriptella ETL files

ejboy (Fyodor Kupolov) — Fri, 07 Dec 2007 21:10:26 GMT

Scriptella ETL provides several ways to execute ETL files:

Invocation from Ant





EtlExecutor.newExecutor(getClass().getResource("etl.xml")).execute(); //Execute etl.xml file loaded from classpath

EtlExecutor.newExecutor(

    servletContext.getResource("/WEB-INF/etl.xml")).execute(); //Execute etl.xml file from web application WEB-INF dir

Integration with Spring Framework

The usage of executor is straightforward:



EtlExecutor exec = (EtlExecutor) beanFactory.getBean("executor");

exec.execute();

See Spring Driver JavaDoc for additional details.

How to produce daily database table dumps in CSV format

ejboy (Fyodor Kupolov) — Fri, 16 Nov 2007 21:08:12 GMT

The following code demonstrates how to produce CSV files with dynamic
file name pattern based on a current day. The produced files have the following naming format:
TABLE_NAME_MM_DD_YYYY.csv







     

        table_name=test

    

          classpath="ojdbc14.jar" user="scott" password="tiger"/>

    

     

        SELECT * FROM ${table_name}

Use Scriptella ETL to run the example.

See How to execute an ETL file from command line, Ant or directly from Java .

Splitting large Scriptella ETL files

ejboy (Fyodor Kupolov) — Wed, 27 Jun 2007 20:33:23 GMT

The following example demonstrates how to split a large Scriptella ETL file into several parts. This example is based on a traditional XML parsed entities approach:

List of Countries and ISO codes Supported by the JVM.

ejboy (Fyodor Kupolov) — Mon, 09 Apr 2007 09:04:33 GMT

The following code displays country names and ISO-codes for the locales supported by the JVM.



        for (Locale locale : Locale.getAvailableLocales()) {

            final String contry = locale.getDisplayCountry();

            if (contry.length() > 0) {

                System.out.println("Country = " + contry + ". ISO code: " + locale.getISO3Country());

            }

        }

Package Name as a Constant

ejboy (Fyodor Kupolov) — Wed, 04 Apr 2007 19:21:14 GMT

getClass().getPackage().getName() is not a reliable solution, because getPackage() can be null depending on a class loader.



static final String PACKAGE_NAME = MyClass.class.getName().substring(0, 

            MyClass.class.getName().lastIndexOf('.'));