src/main/java/org/primefaces/model/timeline/TimelineModel.java
/**
     * Adds a given group to the model.
     *
     * @param group group to be added
     */
Adds a given group to the model.
@param group group to be added
Adds a given group to the model . @param group group to be added
public void addGroup(TimelineGroup<G> group) {
        if (groups == null) {
            groups = new ArrayList<>();
        }
        groups.add(group);
    }
public void addGroup ( TimelineGroup < G > group ) { if ( groups == null ) { groups = new ArrayList < > ( ) ; } groups . add ( group ) ; }
Adds a given group to the model.
Adds a given group to the model .