Talend - DI - Java - Custom Code Components
tJava: This component can be use as trigger component, at start of the job at end of the job.
tJavaRow : this component required main flow so it can be used at end of the Sub Job but not at the start of subjob.
tJavaFlex: this component holds capabilities of tJava & tJavaRows you can use this component for row generation, or at start of job, or at the end of sub job. or individual subjob. It gives you ability to auto propagate data.
Operational usage for each component below.