From 9d8f1f29fc404eaac444d8d8422e889c5ef4d85e Mon Sep 17 00:00:00 2001
From: Charles Oliver Nutter <headius@headius.com>
Date: Wed, 8 Jan 2025 23:48:45 -0600
Subject: [PATCH] Use switch pattern matching to improve handler selection

This eliminates it from profiles, but does not appear to affect
performance significantly.
---
 java/src/json/ext/Generator.java | 34 +++++++++++++++-----------------
 1 file changed, 16 insertions(+), 18 deletions(-)

diff --git a/java/src/json/ext/Generator.java b/java/src/json/ext/Generator.java
index 4ab92805..82d4c0e4 100644
--- a/java/src/json/ext/Generator.java
+++ b/java/src/json/ext/Generator.java
@@ -18,6 +18,7 @@
 import org.jruby.RubyFixnum;
 import org.jruby.RubyFloat;
 import org.jruby.RubyHash;
+import org.jruby.RubyNil;
 import org.jruby.RubyString;
 import org.jruby.RubySymbol;
 import org.jruby.RubyException;
@@ -99,24 +100,21 @@ static <T extends IRubyObject> RubyString generateJson(ThreadContext context, T
     // the best I could get and ignore the warnings
     @SuppressWarnings("unchecked")
     private static <T extends IRubyObject> Handler<? super T> getHandlerFor(Ruby runtime, T object) {
-        switch (((RubyBasicObject) object).getNativeClassIndex()) {
-            case NIL    : return NIL_HANDLER;
-            case TRUE   : return (Handler<T>) TRUE_HANDLER;
-            case FALSE  : return (Handler<T>) FALSE_HANDLER;
-            case FLOAT  : return (Handler<T>) FLOAT_HANDLER;
-            case FIXNUM : return (Handler<T>) FIXNUM_HANDLER;
-            case BIGNUM : return (Handler<T>) BIGNUM_HANDLER;
-            case STRING :
-                if (Helpers.metaclass(object) != runtime.getString()) break;
-                return (Handler<T>) STRING_HANDLER;
-            case ARRAY  :
-                if (Helpers.metaclass(object) != runtime.getArray()) break;
-                return (Handler<T>) ARRAY_HANDLER;
-            case HASH   :
-                if (Helpers.metaclass(object) != runtime.getHash()) break;
-                return (Handler<T>) HASH_HANDLER;
-        }
-        return GENERIC_HANDLER;
+        return switch (object) {
+            case RubyNil o -> NIL_HANDLER;
+            case RubyBoolean.True o -> (Handler<T>) TRUE_HANDLER;
+            case RubyBoolean.False o -> (Handler<T>) FALSE_HANDLER;
+            case RubyFloat o -> (Handler<T>) FLOAT_HANDLER;
+            case RubyFixnum o -> (Handler<T>) FIXNUM_HANDLER;
+            case RubyBignum o -> (Handler<T>) BIGNUM_HANDLER;
+            case RubyString s ->
+                    (Helpers.metaclass(object) != runtime.getString()) ? GENERIC_HANDLER : (Handler<T>) STRING_HANDLER;
+            case RubyArray a ->
+                    (Helpers.metaclass(object) != runtime.getArray()) ? GENERIC_HANDLER : (Handler<T>) ARRAY_HANDLER;
+            case RubyHash h ->
+                    (Helpers.metaclass(object) != runtime.getHash()) ? GENERIC_HANDLER : (Handler<T>) HASH_HANDLER;
+            default -> GENERIC_HANDLER;
+        };
     }