You must note the following points when using the methods of the MediaType class:

• Use the values that are compliant with the standard specifications. The operation is not guaranteed if you specify other non-compliant values.
• Do not register multiple identical keys (including strings that differ only in terms of upper case and lower case) in the map to be specified in the parameters argument of the MediaType(String type, String subtype, java.util.Map<String, String> parameters) constructor. The operation is not guaranteed if you register multiple identical keys.
• The keys type, subtype, and parameters, which are the attributes of the MediaType object to be compared, are not case sensitive when you use the equals(Object obj) method. The value of parameters is case-sensitive.
• The type and subtype, which are attributes of the MediaType object of an argument are not case sensitive when you use the isCompatible(MediaType other) method.
• Do not use the following characters in arguments of the valueOf(String type) method. If you use the following characters, the operation is not guaranteed.
  : ( ) < > @ , ; : / " [ ] ? = { }
  space, linefeed, carriage return, and horizontal tabulation