Add API version checking

MinimallyCorrect · Feb 7, 2016 · 5fa3c49 · 5fa3c49
1 parent ab77443
commit 5fa3c49
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Showing 2 changed files with 25 additions and 7 deletions.
diff --git a/src/main/java/me/nallar/modpatcher/ModPatcher.java b/src/main/java/me/nallar/modpatcher/ModPatcher.java
@@ -26,6 +26,7 @@
  * This behaviour can be disabled by creating the file "libs/modpatcher/NEVER_UPDATE.txt"
  */
 public class ModPatcher {
+	private static final int API_VERSION = 0;
 	private static final Logger log = LogManager.getLogger("ModPatcher");
 	private static final String mcVersion = "@MC_VERSION@";
 	private static final Path neverUpdatePath = Paths.get("./libs/ModPatcher/NEVER_UPDATE.txt").toAbsolutePath();
@@ -194,11 +195,9 @@ private static void addToCurrentClassLoader() {
 		} catch (Exception e) {
 			throw new Error(e);
 		}
-
-		ModPatcherLoadHook.loadHook(requiredVersion, getModPatcherRelease());
 	}
 
-	private static boolean neverUpdate() {
+	static boolean neverUpdate() {
 		return "true".equals(System.getProperty("modPatcher.neverUpdate")) || Files.exists(neverUpdatePath);
 	}
 
@@ -227,9 +226,16 @@ private static void download() {
 	}
 
 	private static void checkClassLoading() {
+		checkClassLoading(true);
+	}
+
+	private static void checkClassLoading(boolean load) {
 		try {
-			ModPatcherLoadHook.class.getName();
+			ModPatcherLoadHook.loadHook(requiredVersion, getModPatcherRelease(), API_VERSION);
 		} catch (NoClassDefFoundError e) {
+			if (!load)
+				throw e;
+
 			loadModPatcher();
 		}
 	}

diff --git a/src/main/java/me/nallar/modpatcher/ModPatcherLoadHook.java b/src/main/java/me/nallar/modpatcher/ModPatcherLoadHook.java
@@ -3,18 +3,30 @@
 import me.nallar.javatransformer.api.JavaTransformer;
 
 class ModPatcherLoadHook {
+	private static final int API_VERSION = 0; //Keep in sync with version in ModPatcher.java
 	private static final String VERSION = "@VERSION@".replace("-SNAPSHOT", "");
 
-	static void loadHook(ModPatcher.Version requiredVersion, String modPatcherRelease) {
+	static void loadHook(ModPatcher.Version requiredVersion, String modPatcherRelease, int apiVersion) {
 		if (ModPatcherLoadHook.class.getClassLoader().getClass().getName().contains("LaunchClassLoader")) {
 			throw new Error("ModPatcher should not be loaded under LaunchClassLoader");
 		}
 
+		if (API_VERSION != apiVersion) {
+			PatcherLog.warn("API version mismatch. Expected " + API_VERSION + ", got " + apiVersion);
+			PatcherLog.warn("API was loaded from: " + JavaTransformer.pathFromClass(ModPatcher.class));
+		}
+
 		ModPatcher.Version current = ModPatcher.Version.of(VERSION);
 
 		if (current.compareTo(requiredVersion) < 0) {
-			JavaTransformer.pathFromClass(ModPatcherTransformer.class).toFile().deleteOnExit();
-			throw new RuntimeException("ModPatcher outdated. Have version: " + VERSION + ", requested version: " + requiredVersion + "\nWill auto-update on next start.");
+			String autoUpdate = "\nWill auto-update on next start.";
+
+			if (ModPatcher.neverUpdate())
+				autoUpdate = "";
+			else
+				JavaTransformer.pathFromClass(ModPatcherTransformer.class).toFile().deleteOnExit();
+
+			throw new RuntimeException("ModPatcher outdated. Have version: " + VERSION + ", requested version: " + requiredVersion + autoUpdate);
 		}
 	}
 }