JUnit: This exception may occur if matchers are combined with raw values

Problem: When JUnit in Java returns next error:

This exception may occur if matchers are combined with raw values:
//incorrect:
someMethod(any(), "raw String");
When using matchers, all arguments have to be provided by matchers.
For example:
//correct:
someMethod(any(), eq("String by matcher"));

Solution: You have are using any() or anyString() or something similar to mock a method parameter. All the parameters of that method have to use any(), anyString()… And if you want to specify some values, you have to use eq().

Example:

//incorrect: because we are not using eq(...) in the parameter where we want to specify the value
when(...).methodName("concrete_value", any(<classType>.class)).thenReturn(...);

//correct: in all parameters we are using any(), eq(), anyString()...
when(...).methodName(eq("concrete_value"), any(<classType>.class)).thenReturn(...);

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