1 /*
   2  * Copyright 1997-2008 Sun Microsystems, Inc.  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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
  20  * CA 95054 USA or visit www.sun.com if you need additional information or
  21  * have any questions.
  22  *
  23  */
  24 
  25 // constant tags in Java .class files
  26 
  27 
  28 enum {
  29   // See jvm.h for shared JVM_CONSTANT_XXX tags
  30   // NOTE: replicated in SA in vm/agent/sun/jvm/hotspot/utilities/ConstantTag.java
  31   // Hotspot specific tags
  32   JVM_CONSTANT_Invalid                  = 0,    // For bad value initialization
  33   JVM_CONSTANT_InternalMin              = 100,  // First implementation tag (aside from bad value of course)
  34   JVM_CONSTANT_UnresolvedClass          = 100,  // Temporary tag until actual use
  35   JVM_CONSTANT_ClassIndex               = 101,  // Temporary tag while constructing constant pool
  36   JVM_CONSTANT_UnresolvedString         = 102,  // Temporary tag until actual use
  37   JVM_CONSTANT_StringIndex              = 103,  // Temporary tag while constructing constant pool
  38   JVM_CONSTANT_UnresolvedClassInError   = 104,  // Error tag due to resolution error
  39   JVM_CONSTANT_Object                   = 105,  // Required for BoundMethodHandle arguments.
  40   JVM_CONSTANT_InternalMax              = 105   // Last implementation tag
  41 };
  42 
  43 
  44 class constantTag VALUE_OBJ_CLASS_SPEC {
  45  private:
  46   jbyte _tag;
  47  public:
  48   bool is_klass() const             { return _tag == JVM_CONSTANT_Class; }
  49   bool is_field () const            { return _tag == JVM_CONSTANT_Fieldref; }
  50   bool is_method() const            { return _tag == JVM_CONSTANT_Methodref; }
  51   bool is_interface_method() const  { return _tag == JVM_CONSTANT_InterfaceMethodref; }
  52   bool is_string() const            { return _tag == JVM_CONSTANT_String; }
  53   bool is_int() const               { return _tag == JVM_CONSTANT_Integer; }
  54   bool is_float() const             { return _tag == JVM_CONSTANT_Float; }
  55   bool is_long() const              { return _tag == JVM_CONSTANT_Long; }
  56   bool is_double() const            { return _tag == JVM_CONSTANT_Double; }
  57   bool is_name_and_type() const     { return _tag == JVM_CONSTANT_NameAndType; }
  58   bool is_utf8() const              { return _tag == JVM_CONSTANT_Utf8; }
  59 
  60   bool is_invalid() const           { return _tag == JVM_CONSTANT_Invalid; }
  61 
  62   bool is_unresolved_klass() const {
  63     return _tag == JVM_CONSTANT_UnresolvedClass || _tag == JVM_CONSTANT_UnresolvedClassInError;
  64   }
  65 
  66   bool is_unresolved_klass_in_error() const {
  67     return _tag == JVM_CONSTANT_UnresolvedClassInError;
  68   }
  69 
  70   bool is_klass_index() const       { return _tag == JVM_CONSTANT_ClassIndex; }
  71   bool is_unresolved_string() const { return _tag == JVM_CONSTANT_UnresolvedString; }
  72   bool is_string_index() const      { return _tag == JVM_CONSTANT_StringIndex; }
  73 
  74   bool is_object() const            { return _tag == JVM_CONSTANT_Object; }
  75 
  76   bool is_klass_reference() const   { return is_klass_index() || is_unresolved_klass(); }
  77   bool is_klass_or_reference() const{ return is_klass() || is_klass_reference(); }
  78   bool is_field_or_method() const   { return is_field() || is_method() || is_interface_method(); }
  79   bool is_symbol() const            { return is_utf8(); }
  80 
  81   constantTag(jbyte tag) {
  82     assert((tag >= 0 && tag <= JVM_CONSTANT_NameAndType) ||
  83            (tag >= JVM_CONSTANT_InternalMin && tag <= JVM_CONSTANT_InternalMax), "Invalid constant tag");
  84     _tag = tag;
  85   }
  86 
  87   jbyte value()                      { return _tag; }
  88 
  89   void print_on(outputStream* st) const PRODUCT_RETURN;
  90 };