Hierarchical/Grouping enum :

We have different statuses and under each status there were sub statuses. We don’t want to check in switch or/if-else each sub statuses so we will check the main status.

public enum Status

{

       ACTIVE1(Group.ACTIVE, "active value 1"),

ACTIVE2(Group.ACTIVE, "active value 2"),

ACTIVE3(Group.ACTIVE, "active value 3"),

       BLOCKED1(Group. BLOCKED, "blocked value 1"),

BLOCKED2(Group. BLOCKED, "blocked value 2"),

BLOCKED3(Group. BLOCKED, "blocked value 3");

public enum Group

{

       ACTIVE, BLOCKED;

}

private String value;

private Group group;

private Status(Group group, final String value)

{

    this.value = value;

    this.group = group;

}

public String getValue()

{

       return this.value;

}

      

public Group getGroup()

{

       return this.group;

}

      

public boolean isInGroup(Group group)

{

    return this.group == group;

}

}

Using this enum in our conditional statements :

switch(statusObject.getGroup())

{

       case ACTIVE:

       case BLOCKED:

}

If(ACTIVE1.isInGroup(Group.ACTIVE)) // true

References:

http://java.dzone.com/articles/enum-tricks-hierarchical-data

http://stackoverflow.com/questions/19680418/how-to-use-enum-with-grouping-and-subgrouping-hierarchy-nesting