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The following image can help you understand the concept called “Realm”.
User Realm
A realm is generally a collection of users with attributes, which may or may not be assigned to roles or groups. Basically we can say that the realm represents a user store. However the WSO2 user realm consists of following four aspects,
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Any user store manager implementation can be written by implementing “UserStoreManager” or extending “AbstractUserStoreManager” or extending any default implementation that is mentioned above.
JDBCUserStoreManager
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