Paper/patches/server/0929-Detect-headless-JREs.patch

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Noah van der Aa <ndvdaa@gmail.com>
Date: Sat, 22 Oct 2022 14:47:45 +0200
Subject: [PATCH] Detect headless JREs

Crashes caused by the missing AWT dependency come up in the support channels fairly often.
This patch detects the missing dependency and stops the server with a clear error message,
containing a link to instructions on how to install a non-headless JRE.

diff --git a/src/main/java/io/papermc/paper/util/ServerEnvironment.java b/src/main/java/io/papermc/paper/util/ServerEnvironment.java
index 6bd0afddbcc461149dfe9a5c7a86fff6ea13a5f1..025731a189cff83576648232a91de69922241123 100644
--- a/src/main/java/io/papermc/paper/util/ServerEnvironment.java
+++ b/src/main/java/io/papermc/paper/util/ServerEnvironment.java
@@ -37,4 +37,14 @@ public class ServerEnvironment {
     public static boolean userIsRootOrAdmin() {
         return RUNNING_AS_ROOT_OR_ADMIN;
     }
+
+    public static boolean isMissingAWTDependency() {
+        try {
+            new java.awt.Color(0);
+        } catch (UnsatisfiedLinkError e) {
+            return true;
+        }
+
+        return false;
+    }
 }
diff --git a/src/main/java/net/minecraft/server/Main.java b/src/main/java/net/minecraft/server/Main.java
index 5962f7a2b185d7d54a0f9e341a4fdf6e6f1c1ec5..88ef769abfa163f923258d1f83d47b28c491eaca 100644
--- a/src/main/java/net/minecraft/server/Main.java
+++ b/src/main/java/net/minecraft/server/Main.java
@@ -155,6 +155,15 @@ public class Main {
                 return;
             }
 
+            // Paper start - Warn on headless
+            if (io.papermc.paper.util.ServerEnvironment.isMissingAWTDependency()) {
+                Main.LOGGER.error("You are using a headless JRE distribution.");
+                Main.LOGGER.error("This distribution is missing certain graphic libraries that the Minecraft server needs to function.");
+                Main.LOGGER.error("For instructions on how to install the non-headless JRE, see https://docs.papermc.io/misc/java-install");
+                return;
+            }
+            // Paper end
+
             org.spigotmc.SpigotConfig.disabledAdvancements = spigotConfiguration.getStringList("advancements.disabled"); // Paper - fix SPIGOT-5885, must be set early in init
             // Paper start - fix SPIGOT-5824
             File file;