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.
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   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
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  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 
  47 private:
  48   ciSymbol* _name;
  49   jint _layout_helper;
  50 
  51 protected:
  52   ciKlass(KlassHandle k_h, ciSymbol* name);
  53   ciKlass(ciSymbol* name, BasicType bt);
  54 
  55   Klass* get_Klass() const {
  56     Klass* k = (Klass*)_metadata;
  57     assert(k != NULL, "illegal use of unloaded klass");
  58     return k;
  59   }
  60 
  61   // Certain subklasses have an associated class loader.
  62   virtual oop loader()             { return NULL; }
  63   virtual jobject loader_handle()  { return NULL; }
  64 
  65   virtual oop protection_domain()             { return NULL; }
  66   virtual jobject protection_domain_handle()  { return NULL; }
  67 
  68   const char* type_string() { return "ciKlass"; }
  69 
  70   void print_impl(outputStream* st);
  71 
  72 public:
  73   ciKlass(KlassHandle k_h);
  74 
  75   // What is the name of this klass?
  76   ciSymbol* name() const { return _name; }
  77 
  78   // What is its layout helper value?
  79   jint layout_helper() { return _layout_helper; }
  80 
  81   bool is_subtype_of(ciKlass* klass);
  82   bool is_subclass_of(ciKlass* klass);
  83   juint super_depth();
  84   juint super_check_offset();
  85   ciKlass* super_of_depth(juint i);
  86   bool can_be_primary_super();
  87   static juint primary_super_limit() { return Klass::primary_super_limit(); }
  88 
  89   // Is this ciObject the ciInstanceKlass representing java.lang.Object()?
  90   virtual bool is_java_lang_Object() const  { return false; }
  91 
  92   // Get the shared parent of two klasses.
  93   ciKlass* least_common_ancestor(ciKlass* k);
  94 
  95   virtual bool is_interface() {
  96     return false;
  97   }
  98 
  99   virtual bool is_abstract() {
 100     return false;
 101   }
 102 
 103   // Does this type (array, class, interface) have no subtypes?
 104   virtual bool is_leaf_type() {
 105     return false;
 106   }
 107 
 108   // Attempt to get a klass using this ciKlass's loader.
 109   ciKlass* find_klass(ciSymbol* klass_name);
 110   // Note:  To find a class from its name string, use ciSymbol::make,
 111   // but consider adding to vmSymbols.hpp instead.
 112 
 113   // Get the instance of java.lang.Class corresponding to this klass.
 114   ciInstance*            java_mirror();
 115 
 116   // Fetch Klass::modifier_flags.
 117   jint                   modifier_flags();
 118 
 119   // Fetch Klass::access_flags.
 120   jint                   access_flags();
 121 
 122   // What kind of ciObject is this?
 123   bool is_klass() const { return true; }
 124 
 125   virtual ciKlass* exact_klass() = 0;
 126 
 127   void print_name_on(outputStream* st);
 128 };
 129 
 130 #endif // SHARE_VM_CI_CIKLASS_HPP