All System routines are read only and has static methods that is why we are able to call all system methods with the class_name.method_name({arg},{arg2},...)

But to leverage full power of java in Talend platform we must know how to create routines with non static methods and how to create objects to call non static methods within Talend routines and in Job design.

Below example will demonstrate how to create a routine with non static methods and call non static methods in CalcUtil by creating objects of Calc Class.

Click Code > Routines > Create routine

// Routine : Calc

package routines;

public class Calc {
 private static int a=0;
 private static int b=0;

 Calc()
 {
   a=0;
   b=0;
 }
 Calc(int a,int b)
 {
   a=0;
   b=0;
 }

 public static int getA() {
  return a;
 }

 public static void setA(int a) {
  Calc.a = a;
 }

 public static int getB() {
  return b;
 }

 public static void setB(int b) {
  Calc.b = b;
 }
 
 public int addition()
 {
  return a+b;
 }
 public int subtract()
 {
  return a-b;
 }
 public int multiply()
 {
  return a*b;
 }
 public int divide()
 {
  return a/b;
 }  
}

Click Code > Routines > Create routine

// Routine : CalcUtil

package routines;

import routines.Calc;

public class CalcUtil {

 public static int add(int num1,int num2){
  Calc c = new Calc();
  Calc.setA(num1);
  Calc.setB(num2);
  return c.addition();
 }
 public static int sub(int num1,int num2){
  Calc c = new Calc(num1,num2);
  return c.subtract();
 }
 
}

Note* :  

SetA and setB are static methods of Calc routine and we are setting values by calling methods with class name.

Talend routines are very useful when you want to write code once and which can be called many times from the same job and more than one jobs.

1. Reusable pieces of Java code
2. Custom code in Java to optimize data processing
3. Improve Job capacity
4. Extend Talend Studio features

There are two types of routines

1. System routines (read only) - System routines are classified according to the type of data they process, such as: numerical, string, date To access the system routines, click Code > Routines > system
2. User routines - User routines is created by user routines to add custom functionality to Talend Studio. Below is the example of User routine which will convert any String into camel case String.

   package routines;
   
   public class ProductUtil {
    public static String toCamelCase(String inputString) {
           String result = "";
           if (inputString.length() == 0) {
               return result;
           }
           char firstChar = inputString.charAt(0);
           char firstCharToUpperCase = Character.toUpperCase(firstChar);
           result = result + firstCharToUpperCase;
           for (int i = 1; i < inputString.length(); i++) {
               char currentChar = inputString.charAt(i);
               char previousChar = inputString.charAt(i - 1);
               if (previousChar == ' ') {
                   char currentCharToUpperCase = Character.toUpperCase(currentChar);
                   result = result + currentCharToUpperCase;
               } else {
                   char currentCharToLowerCase = Character.toLowerCase(currentChar);
                   result = result + currentCharToLowerCase;
               }
           }
           return result;
       }
   }

   

You can call any of your user and system routines from your Job components in order to run them at the same time as your Job. Like I am calling User routine in tmap expression using <routine_name>.<method_name>

ProductUtil.toCamelCase(row1.CUST_FIRST_NAME)

Today, I was upgrading from Talend Open Studio for Data Integration version 5.3.0 to  Talend Open Studio for ESB version 6.1.0,  TOS v6.1.0 have come up with lots of updates. Out of many updates now studio support curved lines to connect components But for me I was comfortable with old straight lines like we have in TOS V5.3.0 To get straight lines click Windows >Preferences > Talend >Appearances> Designer Uncheck Use curved connection style for Job Designer     Click ok, close and open job again.

This post is in continuation with Realtime Response using Talend ESB, here I will show you how to create and run simple REST API. To create MyFirstAPI job I have used TOS ESB v.6.1.1 tRESTRequest_1 will receive a GET request from browser using REST Endpoints and URI pattern "http://localhost:8088/talend/{action}" where action is the query parameter which could be anything and we can get value from URI using this query parameter to perform certain logic on server. In this simple example I am using this query parameter {action} to determine valid/invalid response of API. tFlowToIterate will load a global map variable "requestAction" from the request url. If1 will send Valid response only when globalMap requestAction is equals to valid.

((String)globalMap.get("requestAction")).equals("valid")

In tFixedFlowInput > Edit Schema Create Columns status and message and set status values as "valid" and message value as "Request is Valid". In tXMLMap pass status and message to root Element of response. In tRESTResponse set Return Body Type as Document and Return Status Code as OK(200) Now check for any other action to send invalid response paste below condition in If2. !((String)globalMap.get("requestAction")).equals("valid") And in tFixedFlowInput_2 set status as "invalid" and message as "Request is invalid" Now Run job and Talend ESb will open endpoint from tRESTRequest. http://localhost:8088/ You can call MyFirstAPI job using REST endpoint and URL Pattern from web browser. http://localhost:8088/talend/valid  

In ETL, there are scenarios when data needs to be processed as soon as client upload files into the system. Generally, we use triggers available in Data integration tools for such scenarios like wait for a file or we will trigger process in every 5 mins to check for the new file and process it. We always try to achieve realtime in loading data to our system. Data integration tools do not provide much capabilities to respond to the client in realtime. It can provide fast and efficient way to process and validate data, but to give response to client in case of validation failure and not allowing them to upload wrong files by providing error messages in realtime can be achieved from service based system. I have been facing same problem from 3 mins gap to reach realtime in loading data and to give response back to client in realtime if he commit any mistake in uploading. I was using Talend Open Studio for Data Integration but to reach in realtime I shifted to Talend ESB v.6.1.1. Talend ESB studio has two prospective Integration and Mediation. Integration is same as from Data Integration studio and Talend ESB also comes with Runtime. As both Data Integration studio and ESB studio support same components for data Integration I did not need to do any re-design for the logic in reading and writing data. Now in ESB I just need to wrap my ETL logic inside a RESTful web service which can be called from web browser with client specific parameters and can return response back in realtime. Above snapshot has the request made to the dummy RESTful web service MyFirstAPI using Talend ESB.   In MyFirstAPI job I have used tRESTRequest to receive a request from browser using url pattern "talend/{action}" where action can be anything but job will return valid status only when action is valid. And using tFlowToIterate we can iterate request from clients and perform ETL specific to clients or actions. I will try to cover how to create and deploy Talend ESB RESTful web service in Runtime environment in my future posts. Please let me know your views I hope the above is useful to you.