A long parameter list can indicate that a new structure should be created to wrap the numerous parameters or that the function is doing too many things.
With a maximum number of 4 parameters:
public void doSomething(int param1, int param2, int param3, String param4, long param5) {
...
}
public void doSomething(int param1, int param2, int param3, String param4) {
...
}
Methods annotated with Spring's @RequestMapping (and related shortcut annotations, like @GetRequest) or
@JsonCreator may have a lot of parameters, encapsulation being possible. Such methods are therefore ignored.