I would like to know how to execute own code (from an existing class) into Talend. There is any example?
On the other hand, how I can take the tFileInput variables as input?
You can load a Java library as part of your job execution and refer to the library methods in your components.
Some components expose variables that you can refer to elsewhere. Read the documentation for the relevant component to see which variables are available. If a particular setting isn't exposed by Talend, you can sidestep that by using a global or context variable in the setting. Global and context variables are visible to all components.
To execute your own code do it:
1) Transfer your Class code to routines in Repository:
2) Use components tJava/tJavaRow to use your own code in Jobs: