Talend Project - Child jobs, Functions and Variables

This concluding part of Talend project video explores creating sub/child jobs, how to pass data between the two and different strategies to share the data.

Code in subroutines

// Code from https://www.youtube.com/watch?v=a7-HUU4js9E

package routines;

public class formatEmails {

    public static String formatEmail(char oldRating, char newRating, String typeOfRating) {

       String fEmailText="";

    if (newRating>oldRating) {

    fEmailText=fEmailText+""+typeOfRating +" rating reduced from " +Character.toString(oldRating) +" to "+Character.toString(newRating)  +"
" ;

        }

    if (newRating

    fEmailText=fEmailText+""+typeOfRating +" rating improved from " +Character.toString(oldRating) +" to "+Character.toString(newRating)  +"
" ;

        }

    return fEmailText;

    }

}

It also explores subroutines/functions that helps you reduce the code and modularizes it. 

Check out the detailed video - https://www.youtube.com/watch?v=a7-HUU4js9E

tjavarow component code
/* -- Code from https://www.youtube.com/watch?v=a7-HUU4js9E ---- */ 
String wholepage;  
String ratings;
wholepage=input_row.document.toString(); 
int pos=wholepage.indexOf("composite_val"); 
ratings=wholepage.substring(pos,pos+250).replaceAll("[\\[\\]\"]", "").replaceAll(" \n", " ").replaceAll(" composite_val_vgm","");    String allratingsonly="";
String[] splitratings = ratings.split("composite_val>"); 
int i=0;
context.EmailText=context.EmailText+"

Ratings for : " +context.stock +"
" ;

 for (String eachratingrow : splitratings) 
  {    
   if (eachratingrow.length()>0)  
    { 
  
   if (i==0){  
     output_row.z_growth_rating=Character.toString(eachratingrow.charAt(0));   
        context.EmailText=context.EmailText+formatEmails.formatEmail(input_row.growth_rating.charAt(0), eachratingrow.charAt(0), "Growth");
   }    
   if (i==1)
   {
    output_row.z_momentum_rating=Character.toString(eachratingrow.charAt(0));   
       context.EmailText=context.EmailText+formatEmails.formatEmail(input_row.momentum_rating.charAt(0), eachratingrow.charAt(0), "Momentum");  
     }  
   if (i==2)
   { 
   output_row.z_value_rating=Character.toString(eachratingrow.charAt(0));   
   context.EmailText=context.EmailText+formatEmails.formatEmail(input_row.value_rating.charAt(0), eachratingrow.charAt(0), "Value"); 
   }     
   
   if (i==3)
   {   
    output_row.z_vgm_rating=Character.toString(eachratingrow.charAt(0));  
    context.EmailText=context.EmailText+formatEmails.formatEmail(input_row.vgm_rating.charAt(0), eachratingrow.charAt(0), "VGM"); 
    }  
    i++;
      
      }
  } 
output_row.EmailText=context.EmailText;
  /* - End of Code from https://www.youtube.com/watch?v=a7-HUU4js9E --*/

Talend and Cassandra - Storing data and retrieving

This video explores saving data in Cassandra NoSql database. This video is a continuation of previous one. Apart from saving the data, it also discusses about quick tips on strategies for creating, storing and retrieving data in Cassandra.

Code used in the video

Select * from ss.stockratings where stock='TSLA' order by ratingtime desc limit 1;


Insert into ss.ratings(stock ,ratingtime,id,growth_rating,momentum_rating, value_rating,vgm_rating) values ('TSLA',dateof(now()),now(),'A','D','A','F');

CREATE TABLE ss.stockratings (
 id uuid,
 stock text,
 ratingtime timestamp,
 growth_rating text,
 momentum_rating text,
 value_rating text,
 vgm_rating text,
 PRIMARY KEY ( stock, ratingtime,id)
);

Talend Project - Send mail (tSendMail component)

Talend's tSendMail component can be used to send HTML formatted emails. this Video demonstrates framing a HTML formatted text using the project we were working on.

This is the code that we used in tJavaRow component to extract the rating and create an email body that lists and changes compared to previous rating. Please follow the video get a complete understanding.

/* -- Code from https://www.youtube.com/channel/UCT3bqK2QL93j-IFYFYbvjWQ ---- */ String wholepage; String ratings; wholepage=input_row.document.toString(); int pos=wholepage.indexOf("composite_val"); ratings=wholepage.substring(pos,pos+250).replaceAll("[\\[\\]\"]", "").replaceAll(" \n", " ").replaceAll(" composite_val_vgm",""); //output_row.document = ratings; String allratingsonly=""; String[] splitratings = ratings.split("composite_val>"); int i=0;String EmailText="Ratings for : " +context.stock +"" ;for (String eachratingrow : splitratings) {    if (eachratingrow.length()>0)   { allratingsonly=allratingsonly+";"+ eachratingrow.charAt(0)+"";     //allratingsonly=allratingsonly+eachratingrow+"**;";      if (i==0){  output_row.z_growth_rating=Character.toString(eachratingrow.charAt(0));  
  if ( eachratingrow.charAt(0)>input_row.growth_rating.charAt(0))  {   EmailText=EmailText+"Growth rating reduced from " +input_row.growth_rating+ " To "+ eachratingrow.charAt(0)+"
"; ";   }
      if ( eachratingrow.charAt(0)    {   EmailText=EmailText+"Growth rating improved from " +input_row.growth_rating +" To "+ eachratingrow.charAt(0)+"
";  ";      }  }    if (i==1){ output_row.z_momentum_rating=Character.toString(eachratingrow.charAt(0));   if ( eachratingrow.charAt(0)>input_row.momentum_rating.charAt(0))  {   EmailText=EmailText+"momentum rating reduced from " +input_row.momentum_rating+ " To "+ eachratingrow.charAt(0)+"
"; ";   }
      if ( eachratingrow.charAt(0)    {   EmailText=EmailText+"momentum rating improved from " +input_row.momentum_rating +" To "+ eachratingrow.charAt(0)+"
";  ";      }  }  if (i==2){ output_row.z_value_rating=Character.toString(eachratingrow.charAt(0));   if ( eachratingrow.charAt(0)>input_row.value_rating.charAt(0))  {   EmailText=EmailText+"value rating reduced from " +input_row.value_rating+ " To "+ eachratingrow.charAt(0)+"
"; ";   }
      if ( eachratingrow.charAt(0)    {   EmailText=EmailText+"value rating improved from " +input_row.value_rating +" To "+ eachratingrow.charAt(0)+"
";   ";       }  }     if (i==3){   output_row.z_vgm_rating=Character.toString(eachratingrow.charAt(0));   if ( eachratingrow.charAt(0)>input_row.vgm_rating.charAt(0))  {   EmailText=EmailText+"vgm rating reduced from " +input_row.vgm_rating+ " To "+ eachratingrow.charAt(0)+"
"; ";   }
      if ( eachratingrow.charAt(0)    {   EmailText=EmailText+"vgm rating improved from " +input_row.vgm_rating +" To "+ eachratingrow.charAt(0)+"
";   ";       }  }  i++;
    } } 

output_row.EmailText=EmailText;/* - End of Code from https://www.youtube.com/channel/UCT3bqK2QL93j-IFYFYbvjWQ --*/

If you haven't visited this project from the beginning, Here is the first post about it in this blog - http://sanjaykattimani.blogspot.com/2016/12/talend-project-to-parse-webpage-zackscom.html