code: @Nonnull
      public BugInstance addMethod(String className, String methodName, String methodSig, boolean isStatic) {
          addMethod(MethodAnnotation.fromForeignMethod(className, methodName, methodSig, isStatic));
          return this;
      }
docs: Add a method annotation. If this is the first method annotation added, it
  becomes the primary method annotation.
  
  @param className
  name of the class containing the method
  @param methodName
  name of the method
  @param methodSig
  type signature of the method
  @param isStatic
  true if the method is static, false otherwise
  @return this object