src/hotspot/share/classfile/javaClasses.cpp

rev 54124 : 8218628: Add detailed message to NullPointerException describing what is null.

*** 1514,1524 ****
  
  bool java_lang_Class::offsets_computed = false;
  int  java_lang_Class::classRedefinedCount_offset = -1;
  
  #define CLASS_FIELDS_DO(macro) \
!   macro(classRedefinedCount_offset, k, "classRedefinedCount", int_signature,         false) ; \
    macro(_class_loader_offset,       k, "classLoader",         classloader_signature, false); \
    macro(_component_mirror_offset,   k, "componentType",       class_signature,       false); \
    macro(_module_offset,             k, "module",              module_signature,      false); \
    macro(_name_offset,               k, "name",                string_signature,      false); \
  
--- 1514,1524 ----
  
  bool java_lang_Class::offsets_computed = false;
  int  java_lang_Class::classRedefinedCount_offset = -1;
  
  #define CLASS_FIELDS_DO(macro) \
!   macro(classRedefinedCount_offset, k, "classRedefinedCount", int_signature,         false); \
    macro(_class_loader_offset,       k, "classLoader",         classloader_signature, false); \
    macro(_component_mirror_offset,   k, "componentType",       class_signature,       false); \
    macro(_module_offset,             k, "module",              module_signature,      false); \
    macro(_name_offset,               k, "name",                string_signature,      false); \
  
*** 1959,1968 ****
--- 1959,2000 ----
  static inline bool version_matches(Method* method, int version) {
    assert(version < MAX_VERSION, "version is too big");
    return method != NULL && (method->constants()->version() == version);
  }
  
+ bool java_lang_Throwable::get_method_and_bci(oop throwable, Method** method, int* bci) {
+   objArrayOop bt = (objArrayOop)backtrace(throwable);
+ 
+   if (bt == NULL) {
+     return false;
+   }
+ 
+   oop ms = bt->obj_at(trace_methods_offset);
+   typeArrayOop methods = typeArrayOop(ms);
+   typeArrayOop bcis = (typeArrayOop)bt->obj_at(trace_bcis_offset);
+   objArrayOop mirrors = (objArrayOop)bt->obj_at(trace_mirrors_offset);
+   if ((methods == NULL) || (bcis == NULL) || (mirrors == NULL)) {
+     return false;
+   }
+ 
+   oop m = mirrors->obj_at(0);
+   if (m == NULL) {
+     return false;
+   }
+ 
+   InstanceKlass* holder = InstanceKlass::cast(java_lang_Class::as_Klass(m));
+   int method_id = methods->short_at(0);
+   Method* act_method = holder->method_with_idnum(method_id);
+   if (act_method == NULL) {
+     return false;
+   }
+ 
+   int act_bci = Backtrace::bci_at(bcis->int_at(0));
+   *method = act_method;
+   *bci = act_bci;
+   return true;
+ }
  
  // This class provides a simple wrapper over the internal structure of
  // exception backtrace to insulate users of the backtrace from needing
  // to know what it looks like.
  class BacktraceBuilder: public StackObj {