In Apache Struts, if you have 100 different Struts Actions then you must have 100 different Action classes, one for each Struts Action you define. In large projects this may result in a large number of classes that will be difficult to maintain. It would be desirable if one Action class (see Controller in the diagram below) could implement several related operations, for example, grouping different actions into a few Action classes instead. In this way 100 different Struts Actions could be reduced to just 10 or 20 different classes.