1 /*
   2  * Copyright (c) 1999, 2013, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  *
  23  */
  24 
  25 #ifndef SHARE_VM_CI_CIKLASS_HPP
  26 #define SHARE_VM_CI_CIKLASS_HPP
  27 
  28 #include "ci/ciType.hpp"
  29 
  30 // ciKlass
  31 //
  32 // This class and its subclasses represent Klass*s in the
  33 // HotSpot virtual machine.  In the vm, each Klass* contains an
  34 // embedded Klass object.  ciKlass is subclassed to explicitly
  35 // represent the kind of Klass embedded in the Klass*.  For
  36 // example, a Klass* with an embedded ObjArrayKlass object is
  37 // represented in the ciObject hierarchy by the class
  38 // ciObjArrayKlass.
  39 class ciKlass : public ciType {
  40   CI_PACKAGE_ACCESS
  41   friend class ciEnv;
  42   friend class ciField;
  43   friend class ciMethod;
  44   friend class ciMethodData;
  45   friend class ciObjArrayKlass;
  46   friend class ciReceiverTypeData;
  47 
  48 private:
  49   ciSymbol* _name;
  50   jint _layout_helper;
  51 
  52 protected:
  53   ciKlass(KlassHandle k_h, ciSymbol* name);
  54   ciKlass(ciSymbol* name, BasicType bt);
  55 
  56   Klass* get_Klass() const {
  57     Klass* k = (Klass*)_metadata;
  58     assert(k != NULL, "illegal use of unloaded klass");
  59     return k;
  60   }
  61 
  62   // Certain subklasses have an associated class loader.
  63   virtual oop loader()             { return NULL; }
  64   virtual jobject loader_handle()  { return NULL; }
  65 
  66   virtual oop protection_domain()             { return NULL; }
  67   virtual jobject protection_domain_handle()  { return NULL; }
  68 
  69   const char* type_string() { return "ciKlass"; }
  70 
  71   void print_impl(outputStream* st);
  72 
  73 public:
  74   ciKlass(KlassHandle k_h);
  75 
  76   // What is the name of this klass?
  77   ciSymbol* name() const { return _name; }
  78 
  79   // What is its layout helper value?
  80   jint layout_helper() { return _layout_helper; }
  81 
  82   bool is_subtype_of(ciKlass* klass);
  83   bool is_subclass_of(ciKlass* klass);
  84   juint super_depth();
  85   juint super_check_offset();
  86   ciKlass* super_of_depth(juint i);
  87   bool can_be_primary_super();
  88   static juint primary_super_limit() { return Klass::primary_super_limit(); }
  89 
  90   // Is this ciObject the ciInstanceKlass representing java.lang.Object()?
  91   virtual bool is_java_lang_Object() const  { return false; }
  92 
  93   // Get the shared parent of two klasses.
  94   ciKlass* least_common_ancestor(ciKlass* k);
  95 
  96   virtual bool is_interface() {
  97     return false;
  98   }
  99 
 100   virtual bool is_abstract() {
 101     return false;
 102   }
 103 
 104   // Does this type (array, class, interface) have no subtypes?
 105   virtual bool is_leaf_type() {
 106     return false;
 107   }
 108 
 109   // Attempt to get a klass using this ciKlass's loader.
 110   ciKlass* find_klass(ciSymbol* klass_name);
 111   // Note:  To find a class from its name string, use ciSymbol::make,
 112   // but consider adding to vmSymbols.hpp instead.
 113 
 114   // Get the instance of java.lang.Class corresponding to this klass.
 115   ciInstance*            java_mirror();
 116 
 117   // Fetch Klass::modifier_flags.
 118   jint                   modifier_flags();
 119 
 120   // Fetch Klass::access_flags.
 121   jint                   access_flags();
 122 
 123   // What kind of ciObject is this?
 124   bool is_klass() const { return true; }
 125 
 126   virtual ciKlass* exact_klass() = 0;
 127 
 128   void print_name_on(outputStream* st);
 129 
 130   const char* external_name() const;
 131 };
 132 
 133 #endif // SHARE_VM_CI_CIKLASS_HPP