If a Method can not be found: a log.warn is enough.

It can happen with correct code dealing with interfaces

pom.xml

@@ -175,6 +175,11 @@
 			<artifactId>mockito-all</artifactId>
 			<version>1.10.8</version>
 		</dependency>
+		<dependency>
+			<groupId>commons-logging</groupId>
+			<artifactId>commons-logging</artifactId>
+			<version>1.2</version>
+		</dependency>
 		<!-- dependencies for jp.co.worksap.oss.findbugs.jpa package -->
 		<dependency>
 			<groupId>org.hibernate.javax.persistence</groupId>

src/main/java/jp/co/worksap/oss/findbugs/guava/UnexpectedAccessDetector.java

@@ -8,6 +8,8 @@
 import org.apache.bcel.classfile.AnnotationEntry;
 import org.apache.bcel.classfile.JavaClass;
 import org.apache.bcel.classfile.Method;
+import org.apache.commons.logging.Log;
+import org.apache.commons.logging.LogFactory;
 
 import com.google.common.annotations.VisibleForTesting;
 
@@ -29,6 +31,8 @@ public class UnexpectedAccessDetector extends BytecodeScanningDetector {
 	@Nonnull
 	private final BugReporter bugReporter;
 
+	private final transient Log log = LogFactory.getLog(this.getClass());
+
 	/**
 	 * @param bugReporter
 	 */
@@ -68,7 +72,7 @@ void verifyVisibility(ClassDescriptor invokedClass, MethodDescriptor invokedMeth
 		JavaClass bcelClass = Repository.getRepository().loadClass(invokedClass.getDottedClassName());
 		Method bcelMethod = findMethod(bcelClass, invokedMethod);
 
-		if (checkVisibility(bcelMethod) && checkAnnotated(bcelMethod)) {
+		if (bcelMethod != null && checkVisibility(bcelMethod) && checkAnnotated(bcelMethod)) {
 			BugInstance bug = new BugInstance(this, "GUAVA_UNEXPECTED_ACCESS_TO_VISIBLE_FOR_TESTING", HIGH_PRIORITY);
 			if (reportCaller) {
 				bug.addCalledMethod(this).addClassAndMethod(this).addSourceLine(this);
@@ -85,8 +89,8 @@ Method findMethod(JavaClass bcelClass, MethodDescriptor invokedMethod) {
 				return bcelMethod;
 			}
 		}
-
-		throw new IllegalArgumentException("Method not found: " + invokedMethod);
+		log.warn("Method not found: " + invokedMethod);
+		return null;
 	}
 
 	/**