code: void checkInterfaces(ClassFile cf) throws ConstantPoolException {
          int ni = cf.interfaces.length;
          for (int i = 0; i < ni; i++) {
              String iname = cf.getInterfaceName(i);
              DeprData dd = db.getTypeDeprecated(iname);
              if (dd != null) {
                  printType("scan.out.implements", cf, iname, dd.isForRemoval());
              }
          }
      }
docs: Checks the interfaces of this class.
  
  @param cf the ClassFile of this class
  @throws ConstantPoolException if a constant pool entry cannot be found