if block in talend

Question

hi , i am new to talend , can anyone tell me how to properly use "if" blocks  in talend ?? i see  that we can use the if bloc kin a lot of spots but i cannot figure out where , all i know until now , is that "if" block is possible when linking 2 components , also in a map in filter section  and also in some java components ; but where else can we invoke the "if" can we do it between sub jobs and in other spots ?

Answer 1

Hi, @Aminegac,

If/else statement

In the Expression Builder, the if / else statement can be written as follows:

condition?value if true:value if false

You can perform a null test before calling a Java method; otherwise, it will throw a null pointer exception if the input data contains a null value. For example:

row1.Postal_code==null?null:row1.Postal_code.toUpperCase()

Hope this helps.

To learn more about Talend' it's recommended to join Talend training today.

Thanks.

Comments

okay , thank you :)

Answer 2

@Aminegac,

In the Basic settings view of a Run if connection, you can set the condition to the subJob in Java.

You can use variables in your condition. Pressing Ctrl+Space allows you to access all global and context variables. 

Procedure

1. Create a Job and drop three components to the design workspace: a tFileInputDelimited, a tLogRow, and a tMsgBox.
2. Connect the components as follows:

   • Right-click the tFileInputDelimited component, select Row > Main from the contextual menu, and click the tLogRow component.

   • Right-click the tFileInputDelimited component, select Trigger > Run if from the contextual menu, and click the tMsgBox component.

3. Configure the tFileInputDelimited component so that it reads a file that contains no data rows.
4. Select the Run if connection between the tFileInputDelimited component and the tMsgBox component, and click the Component view. In the Condition field on the Basic settings tab, pressing Ctrl+Space to access the variable list, and select the NB_LINE variable of the tFileInputDelimited component. Edit the condition as follows:

   ((Integer)globalMap.get("tFileInputDelimited_1_NB_LINE"))==0

5. Go to the Component view of the tMsgBox component, and enter a message, "No data is read from the file" for example, in the Message field.
6. Save and run the Job. You should see the message you defined in the tMsgBox component.

Comments

thank you @Nikita