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E020 Interface Association Not One Way

Umple semantic error reported when an association to an interface is declared to be bidirectional or pointing from the interface.

An association can be declared from a class to an interface, but if this is done, it must be one way using the '->' notation. The reason for this is that no concrete methods can be generated in an interface.

Example

// This example generates the message
class X20classintfarrow {
  1 -- * IA;
}

interface IA {}
      

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Another Example

// This example generates the message
class X20classintfarrow {
  1 <- * IA;
}

interface IA {}
      

Load the above code into UmpleOnline