Parameter Resolver

Let's learn how to perform parameter resolution in JUnit 5.

Parameter resolution

Parameter resolution is accomplished by implementations of the extension interface ParameterResolver. It has two methods to implement.

  • The first method, boolean supportsParameter(ParameterContext parameterContext, ExtensionContext extensionContext) throws ParameterResolutionException, checks if this resolver supports the resolution of a parameter.
  • The second method, Object resolveParameter(ParameterContext parameterContext, ExtensionContext extensionContext) throws ParameterResolutionException, resolves the parameter and returns its value.

The type of the first parameter of these two methods is ParameterContext. It contains information about the parameter to resolve.

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