private Object resolveParameter()

in junit-jupiter-engine/src/main/java/org/junit/jupiter/engine/execution/ExecutableInvoker.java [188:241]
41 lines of code
7 McCabe index (conditional complexity)

	private Object resolveParameter(ParameterContext parameterContext, Executable executable,
			ExtensionContext extensionContext, ExtensionRegistry extensionRegistry) {

		try {
			// @formatter:off
			List<ParameterResolver> matchingResolvers = extensionRegistry.stream(ParameterResolver.class)
					.filter(resolver -> resolver.supportsParameter(parameterContext, extensionContext))
					.collect(toList());
			// @formatter:on

			if (matchingResolvers.isEmpty()) {
				throw new ParameterResolutionException(
					String.format("No ParameterResolver registered for parameter [%s] in %s [%s].",
						parameterContext.getParameter(), asLabel(executable), executable.toGenericString()));
			}

			if (matchingResolvers.size() > 1) {
				// @formatter:off
				String resolvers = matchingResolvers.stream()
						.map(StringUtils::defaultToString)
						.collect(joining(", "));
				// @formatter:on
				throw new ParameterResolutionException(
					String.format("Discovered multiple competing ParameterResolvers for parameter [%s] in %s [%s]: %s",
						parameterContext.getParameter(), asLabel(executable), executable.toGenericString(), resolvers));
			}

			ParameterResolver resolver = matchingResolvers.get(0);
			Object value = resolver.resolveParameter(parameterContext, extensionContext);
			validateResolvedType(parameterContext.getParameter(), value, executable, resolver);

			logger.trace(() -> String.format(
				"ParameterResolver [%s] resolved a value of type [%s] for parameter [%s] in %s [%s].",
				resolver.getClass().getName(), (value != null ? value.getClass().getName() : null),
				parameterContext.getParameter(), asLabel(executable), executable.toGenericString()));

			return value;
		}
		catch (ParameterResolutionException ex) {
			throw ex;
		}
		catch (Throwable throwable) {
			UnrecoverableExceptions.rethrowIfUnrecoverable(throwable);

			String message = String.format("Failed to resolve parameter [%s] in %s [%s]",
				parameterContext.getParameter(), asLabel(executable), executable.toGenericString());

			if (StringUtils.isNotBlank(throwable.getMessage())) {
				message += ": " + throwable.getMessage();
			}

			throw new ParameterResolutionException(message, throwable);
		}
	}