Adapter pattern comes into play when we need to connect two incompatible interfaces. Like how we use the Arrays.asList method to convert an array to a list. This design pattern falls under structural category. It is easy to implement and useful when need to integrate something with legacy code which can't be modified.

In the example, EmployeeClient.java file fetches employee data from three different sources, DB, LDAP and CSV. And to overcome the differences among the data sources and maintain uniformity of data for the client, we use two adapters, namely EmployeeLdapAdapter.java and EmployeeCSVAdapter.java.

• Don't complicate
• Mulitple Adapters
• Don't add functionality