src/hotspot/share/classfile/classFileParser.cpp

*** 55,64 ****
--- 55,65 ----
  #include "oops/method.hpp"
  #include "oops/oop.inline.hpp"
  #include "oops/symbol.hpp"
  #include "prims/jvmtiExport.hpp"
  #include "prims/jvmtiThreadState.hpp"
+ #include "runtime/arguments.hpp"
  #include "runtime/handles.inline.hpp"
  #include "runtime/javaCalls.hpp"
  #include "runtime/perfData.hpp"
  #include "runtime/reflection.hpp"
  #include "runtime/safepointVerifiers.hpp"
*** 87,96 ****
--- 88,98 ----
  
  // We add assert in debug mode when class format is not checked.
  
  #define JAVA_CLASSFILE_MAGIC              0xCAFEBABE
  #define JAVA_MIN_SUPPORTED_VERSION        45
+ #define JAVA_PREVIEW_MINOR_VERSION        65535
  
  // Used for two backward compatibility reasons:
  // - to check for new additions to the class file format in JDK1.5
  // - to check for bug fixes in the format checker in JDK1.5
  #define JAVA_1_5_VERSION                  49
*** 4698,4713 ****
    return ((is_public && is_protected) ||
            (is_public && is_private) ||
            (is_protected && is_private));
  }
  
! static bool is_supported_version(u2 major, u2 minor){
    const u2 max_version = JVM_CLASSFILE_MAJOR_VERSION;
!   return (major >= JAVA_MIN_SUPPORTED_VERSION) &&
!          (major <= max_version) &&
!          ((major != max_version) ||
!           (minor <= JVM_CLASSFILE_MINOR_VERSION));
  }
  
  void ClassFileParser::verify_legal_field_modifiers(jint flags,
                                                     bool is_interface,
                                                     TRAPS) const {
--- 4700,4760 ----
    return ((is_public && is_protected) ||
            (is_public && is_private) ||
            (is_protected && is_private));
  }
  
! static void verify_class_version(u2 major, u2 minor, Symbol* class_name, TRAPS){
    const u2 max_version = JVM_CLASSFILE_MAJOR_VERSION;
!   if (major != JAVA_MIN_SUPPORTED_VERSION) { // All 45.* are ok including 45.65535
!     if (minor == JAVA_PREVIEW_MINOR_VERSION) {
!       if (major != max_version) {
!         ResourceMark rm(THREAD);
!         Exceptions::fthrow(
!           THREAD_AND_LOCATION,
!           vmSymbols::java_lang_UnsupportedClassVersionError(),
!           "%s (class file version %u.%u) was compiled with preview features that are unsupported. "
!           "This version of the Java Runtime only recognizes preview features for class file version %u.%u",
!           class_name->as_C_string(), major, minor, JVM_CLASSFILE_MAJOR_VERSION, JAVA_PREVIEW_MINOR_VERSION);
!         return;
!       }
! 
!       if (!Arguments::enable_preview()) {
!         ResourceMark rm(THREAD);
!         Exceptions::fthrow(
!           THREAD_AND_LOCATION,
!           vmSymbols::java_lang_UnsupportedClassVersionError(),
!           "Preview features are not enabled for %s (class file version %u.%u). Try running with '--enable-preview'",
!           class_name->as_C_string(), major, minor);
!         return;
!       }
! 
!     } else { // minor != JAVA_PREVIEW_MINOR_VERSION
!       if (major > max_version) {
!         ResourceMark rm(THREAD);
!         Exceptions::fthrow(
!           THREAD_AND_LOCATION,
!           vmSymbols::java_lang_UnsupportedClassVersionError(),
!           "%s has been compiled by a more recent version of the Java Runtime (class file version %u.%u), "
!           "this version of the Java Runtime only recognizes class file versions up to %u.0",
!           class_name->as_C_string(), major, minor, JVM_CLASSFILE_MAJOR_VERSION);
!       } else if (major < JAVA_MIN_SUPPORTED_VERSION) {
!         ResourceMark rm(THREAD);
!         Exceptions::fthrow(
!           THREAD_AND_LOCATION,
!           vmSymbols::java_lang_UnsupportedClassVersionError(),
!           "%s (class file version %u.%u) was compiled with an invalid major version",
!           class_name->as_C_string(), major, minor);
!       } else if (minor != 0) {
!         ResourceMark rm(THREAD);
!         Exceptions::fthrow(
!           THREAD_AND_LOCATION,
!           vmSymbols::java_lang_UnsupportedClassVersionError(),
!           "%s (class file version %u.%u) was compiled with an invalid non-zero minor version",
!           class_name->as_C_string(), major, minor);
!       }
!     }
!   }
  }
  
  void ClassFileParser::verify_legal_field_modifiers(jint flags,
                                                     bool is_interface,
                                                     TRAPS) const {
*** 5547,5556 ****
--- 5594,5610 ----
        ResourceMark rm;
        const char* module_name = (module_entry->name() == NULL) ? UNNAMED_MODULE : module_entry->name()->as_C_string();
        ik->print_class_load_logging(_loader_data, module_name, _stream);
      }
  
+     if (ik->minor_version() == JAVA_PREVIEW_MINOR_VERSION &&
+         ik->major_version() != JAVA_MIN_SUPPORTED_VERSION &&
+         log_is_enabled(Info, class, preview)) {
+       ResourceMark rm;
+       log_info(class, preview)("Loading preview feature type %s", ik->external_name());
+     }
+ 
      if (log_is_enabled(Debug, class, resolve))  {
        ResourceMark rm;
        // print out the superclass.
        const char * from = ik->external_name();
        if (ik->java_super() != NULL) {
*** 5862,5885 ****
        _major_version,
        _minor_version);
    }
  
    // Check version numbers - we check this even with verifier off
!   if (!is_supported_version(_major_version, _minor_version)) {
!     ResourceMark rm(THREAD);
!     Exceptions::fthrow(
!       THREAD_AND_LOCATION,
!       vmSymbols::java_lang_UnsupportedClassVersionError(),
!       "%s has been compiled by a more recent version of the Java Runtime (class file version %u.%u), "
!       "this version of the Java Runtime only recognizes class file versions up to %u.%u",
!       _class_name->as_C_string(),
!       _major_version,
!       _minor_version,
!       JVM_CLASSFILE_MAJOR_VERSION,
!       JVM_CLASSFILE_MINOR_VERSION);
!     return;
!   }
  
    stream->guarantee_more(3, CHECK); // length, first cp tag
    u2 cp_size = stream->get_u2_fast();
  
    guarantee_property(
--- 5916,5926 ----
        _major_version,
        _minor_version);
    }
  
    // Check version numbers - we check this even with verifier off
!   verify_class_version(_major_version, _minor_version, _class_name, CHECK);
  
    stream->guarantee_more(3, CHECK); // length, first cp tag
    u2 cp_size = stream->get_u2_fast();
  
    guarantee_property(