Throw meaningful exception if JUnit 4.9 is not present

SpringJUnit4ClassRunner, SpringClassRule, and SpringMethodRule now
throw an IllegalStateException with a meaningful message if JUnit 4.9
is not present in the classpath (specifically if
org.junit.runners.model.MultipleFailureException cannot be loaded).

Issue: SPR-13521

Author: sbrannen

spring-test/src/main/java/org/springframework/test/context/junit4/SpringJUnit4ClassRunner.java

@@ -21,6 +21,7 @@
 
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
+
 import org.junit.Ignore;
 import org.junit.Test;
 import org.junit.internal.runners.model.ReflectiveCallable;
@@ -45,6 +46,7 @@
 import org.springframework.test.context.junit4.statements.RunBeforeTestMethodCallbacks;
 import org.springframework.test.context.junit4.statements.SpringFailOnTimeout;
 import org.springframework.test.context.junit4.statements.SpringRepeat;
+import org.springframework.util.ClassUtils;
 import org.springframework.util.ReflectionUtils;
 
 /**
@@ -90,7 +92,18 @@ public class SpringJUnit4ClassRunner extends BlockJUnit4ClassRunner {
 
 	private static final Method withRulesMethod;
 
+	// Used by RunAfterTestClassCallbacks and RunAfterTestMethodCallbacks
+	private static final String MULTIPLE_FAILURE_EXCEPTION_CLASS_NAME = "org.junit.runners.model.MultipleFailureException";
+
 	static {
+		boolean junit4dot9Present = ClassUtils.isPresent(MULTIPLE_FAILURE_EXCEPTION_CLASS_NAME,
+			SpringJUnit4ClassRunner.class.getClassLoader());
+		if (!junit4dot9Present) {
+			throw new IllegalStateException(String.format(
+				"Failed to find class [%s]: SpringJUnit4ClassRunner requires JUnit 4.9 or higher.",
+				MULTIPLE_FAILURE_EXCEPTION_CLASS_NAME));
+		}
+
 		withRulesMethod = ReflectionUtils.findMethod(SpringJUnit4ClassRunner.class, "withRules",
 				FrameworkMethod.class, Object.class, Statement.class);
 		if (withRulesMethod == null) {

spring-test/src/main/java/org/springframework/test/context/junit4/rules/SpringClassRule.java

@@ -34,6 +34,7 @@
 import org.springframework.test.context.junit4.statements.RunAfterTestClassCallbacks;
 import org.springframework.test.context.junit4.statements.RunBeforeTestClassCallbacks;
 import org.springframework.util.Assert;
+import org.springframework.util.ClassUtils;
 
 /**
  * {@code SpringClassRule} is a custom JUnit {@link TestRule} that supports
@@ -96,6 +97,19 @@ public class SpringClassRule implements TestRule {
 	private static final Map<Class<?>, TestContextManager> testContextManagerCache =
 			new ConcurrentHashMap<Class<?>, TestContextManager>(64);
 
+	// Used by RunAfterTestClassCallbacks
+	private static final String MULTIPLE_FAILURE_EXCEPTION_CLASS_NAME = "org.junit.runners.model.MultipleFailureException";
+
+	static {
+		boolean junit4dot9Present = ClassUtils.isPresent(MULTIPLE_FAILURE_EXCEPTION_CLASS_NAME,
+			SpringClassRule.class.getClassLoader());
+		if (!junit4dot9Present) {
+			throw new IllegalStateException(String.format(
+				"Failed to find class [%s]: SpringClassRule requires JUnit 4.9 or higher.",
+				MULTIPLE_FAILURE_EXCEPTION_CLASS_NAME));
+		}
+	}
+
 
 	/**
 	 * Apply <em>class-level</em> features of the <em>Spring TestContext

spring-test/src/main/java/org/springframework/test/context/junit4/rules/SpringMethodRule.java

@@ -33,6 +33,7 @@
 import org.springframework.test.context.junit4.statements.RunPrepareTestInstanceCallbacks;
 import org.springframework.test.context.junit4.statements.SpringFailOnTimeout;
 import org.springframework.test.context.junit4.statements.SpringRepeat;
+import org.springframework.util.ClassUtils;
 import org.springframework.util.ReflectionUtils;
 
 /**
@@ -93,6 +94,19 @@ public class SpringMethodRule implements MethodRule {
 
 	private static final Log logger = LogFactory.getLog(SpringMethodRule.class);
 
+	// Used by RunAfterTestMethodCallbacks
+	private static final String MULTIPLE_FAILURE_EXCEPTION_CLASS_NAME = "org.junit.runners.model.MultipleFailureException";
+
+	static {
+		boolean junit4dot9Present = ClassUtils.isPresent(MULTIPLE_FAILURE_EXCEPTION_CLASS_NAME,
+			SpringMethodRule.class.getClassLoader());
+		if (!junit4dot9Present) {
+			throw new IllegalStateException(String.format(
+				"Failed to find class [%s]: SpringMethodRule requires JUnit 4.9 or higher.",
+				MULTIPLE_FAILURE_EXCEPTION_CLASS_NAME));
+		}
+	}
+
 
 	/**
 	 * Apply <em>instance-level</em> and <em>method-level</em> features of