public boolean isJavaLibraryClass(){
  if (name.startsWith("java.") || name.startsWith("sun.") || name.startsWith("javax.")|| name.startsWith("com.sun.")|| name.startsWith("org.omg.")|| name.startsWith("org.xml."))   return true;
  return false;
}

public boolean isJavaLibraryClass ( ) { if ( name . startsWith ( "java." ) || name . startsWith ( "sun." ) || name . startsWith ( "javax." ) || name . startsWith ( "com.sun." ) || name . startsWith ( "org.omg." ) || name . startsWith ( "org.xml." ) ) return true ; return false ; }
sometimes we need to know which class is a jdk class . there is no simple way to distinguish a user class and a jdk class , here we use the package prefix as the heuristic .
