Hi,
sorry for the late post. Last week half of my family was down with the flu.
So first I think I get the reason for the problem. I run into the self error at creating an example. It seems that you must define a initial value for your context variable. Talend is using Double and not the native type double. So the += operator throws a NullPointerException.
Anyway here is my solution:
Code in tJavaRow
output_row.orderId = input_row.orderId;
output_row.orderText = input_row.orderText;
context.sum+= input_row.orderId;
Code in tJava
System.out.println("The sum of all order ids is: " + context.sum);
And the output of the job:
1|Mr. Jones first order
2|Mr. Jones second order
3|The third order of Mr. Jones
6|Mrs. Tompson first ordr
7|Mrs. Tompson second order
8|Mrs. Tompson order number third
18|Mrs. Jones only one order
19|Mr. Albert only one order
20|Mrs. Albert first order
21|Mrs. Albert second order
22|Mrs. Albert third order
The sum of all order ids is: 127.0
The jobs selects for some customer orders from a database and calculates the sum of the customerId.
Bye
Volker