Breaking change: Make deprecated Java gencode PARSER variable private.

This was marked deprecated ~8 years ago.

PiperOrigin-RevId: 584690916

Author: zhangskz

src/google/protobuf/compiler/java/helpers.h

@@ -344,13 +344,6 @@ inline bool HasHasbit(const FieldDescriptor* descriptor) {
   return internal::cpp::HasHasbit(descriptor);
 }
 
-// Whether generate classes expose public PARSER instances.
-inline bool ExposePublicParser(const FileDescriptor* descriptor) {
-  // TODO: Mark the PARSER private in 3.1.x releases.
-  return FileDescriptorLegacy(descriptor).syntax() ==
-         FileDescriptorLegacy::Syntax::SYNTAX_PROTO2;
-}
-
 // Whether unknown enum values are kept (i.e., not stored in UnknownFieldSet
 // but in the message and can be queried using additional getters that return
 // ints.

src/google/protobuf/compiler/java/message.cc

@@ -1140,7 +1140,7 @@ void ImmutableMessageGenerator::GenerateExtensionRegistrationCode(
 // ===================================================================
 void ImmutableMessageGenerator::GenerateParser(io::Printer* printer) {
   printer->Print(
-      "$visibility$ static final com.google.protobuf.Parser<$classname$>\n"
+      "private static final com.google.protobuf.Parser<$classname$>\n"
       "    PARSER = new com.google.protobuf.AbstractParser<$classname$>() {\n"
       "  @java.lang.Override\n"
       "  public $classname$ parsePartialFrom(\n"
@@ -1173,9 +1173,6 @@ void ImmutableMessageGenerator::GenerateParser(io::Printer* printer) {
       "  return PARSER;\n"
       "}\n"
       "\n",
-      "visibility",
-      ExposePublicParser(descriptor_->file()) ? "@java.lang.Deprecated public"
-                                              : "private",
       "classname", descriptor_->name());
 }
 

src/google/protobuf/compiler/java/message_field.cc

@@ -62,11 +62,7 @@ void SetMessageVariables(
            : ""});
   (*variables)["on_changed"] = "onChanged();";
   (*variables)["ver"] = GeneratedCodeVersionSuffix();
-  (*variables)["get_parser"] =
-      ExposePublicParser(descriptor->message_type()->file()) &&
-              context->options().opensource_runtime
-          ? "PARSER"
-          : "parser()";
+  (*variables)["get_parser"] = "parser()";
 
   if (HasHasbit(descriptor)) {
     // For singular messages and builders, one bit is used for the hasField bit.