Warn for using V2/third party manifests

Author: PhoenixVX

cli/src/main/java/org/mcphackers/mcp/main/MainCLI.java

@@ -58,6 +58,10 @@ public MainCLI(String[] args) {
 		String version = null;
 		Path versionPath = Paths.get(MCPPaths.VERSION);
 		VersionParser versionParser = VersionParser.getInstance();
+		if (!VersionParser.mappingsJson.equals(VersionParser.DEFAULT_JSON)) {
+			warning("Using old or third party manifest URL: " + VersionParser.mappingsJson);
+			warning("If this is not intentional, please update versionUrl in options.cfg to " + VersionParser.DEFAULT_JSON);
+		}
 		List<VersionData> versions = versionParser.getVersions();
 		if (Files.exists(versionPath)) {
 			try {

gui/src/main/java/org/mcphackers/mcp/main/MainGUI.java

@@ -107,6 +107,10 @@ private void initialize() {
 				e.printStackTrace();
 			}
 		}
+		if (!VersionParser.mappingsJson.equals(VersionParser.DEFAULT_JSON)) {
+			warning("Using old or third party manifest URL: " + VersionParser.mappingsJson);
+			warning("If this is not intentional, please update versionUrl in options.cfg to " + VersionParser.DEFAULT_JSON);
+		}
 		frame = new MCPFrame(this);
 		if (Util.getJavaVersion() > 8) {
 			warning("JDK " + Util.getJavaVersion() + " is being used! Java 8 is recommended.");

src/main/java/org/mcphackers/mcp/tools/versions/VersionParser.java

@@ -19,7 +19,8 @@
 
 public class VersionParser {
 
-	public static String mappingsJson = "https://mcphackers.org/versionsV3/versions.json";
+	public static final String DEFAULT_JSON = "https://mcphackers.org/versionsV3/versions.json";
+	public static String mappingsJson = DEFAULT_JSON;
 	private static VersionParser INSTANCE;
 
 	private final List<VersionData> versions = new ArrayList<>();