/** A class for type symbols.
 * Type variables are represented by instances of this class,  // 类型变量用这个类来表示
 * classes and packages by instances of subclasses.  // 类和包用子类来表示
 */
public class TypeSymbol extends Symbol implements TypeParameterElement {
   ...
}

/** A class for package symbols
 */
public class PackageSymbol extends TypeSymbol  implements PackageElement {

    public Scope members_field;
    public Name fullname;
    public ClassSymbol package_info; // see bug 6443073
    ...
}

/** A class for class symbols
 */
public class ClassSymbol extends TypeSymbol implements TypeElement {

    /** a scope for all class members; variables, methods and inner classes
     *  type parameters are not part of this scope
     *  
     *  所有类成员的一个作用域。变量，方法和内部类 类型参数不是这个作用域的一部分
     */
    public Scope members_field;

    /** the fully qualified name of the class, i.e. pck.outer.inner.
     *  null for anonymous classes
     *  
     *  类的全限定名,对于匿名类为空
     */
    public Name fullname;

    /** the fully qualified name of the class after converting to flat
     *  representation, i.e. pck.outer$inner,
     *  set externally for local and anonymous classes
     *  
     *  类的全限定名,为本地和匿名类也进行设置
     */
    public Name flatname;

    /** the sourcefile where the class came from
     */
    public JavaFileObject sourcefile;

    /** the classfile from where to load this class
     *  this will have extension .class or .java
     */
    public JavaFileObject classfile;

    /** the list of translated local classes (used for generating InnerClasses attribute)
     */
    public List<ClassSymbol> trans_local;

    /** the constant pool of the class
     */
    public Pool pool;
    ...
}