Possible fix for -nojline printing blank lines

src/main/java/net/minecraft/server/ThreadCommandReader.java

@@ -8,6 +8,7 @@ import java.io.InputStreamReader;
 import java.util.logging.Level;
 import java.util.logging.Logger;
 import jline.ConsoleReader;
+import org.bukkit.craftbukkit.Main;
 // CraftBukkit end
 
 public class ThreadCommandReader extends Thread {
@@ -22,16 +23,15 @@ public class ThreadCommandReader extends Thread {
         // CraftBukkit start
         ConsoleReader bufferedreader = this.server.reader;
         String s = null;
-        String jlineTerminalSetting = org.bukkit.craftbukkit.Main.jlineTerminalSetting;
         // CraftBukkit end
 
         try {
             while (!this.server.isStopped && MinecraftServer.isRunning(this.server)) {
                 // CraftBukkit start - JLine disabling compatibility
-                if (jlineTerminalSetting != null && jlineTerminalSetting.equals("jline.UnsupportedTerminal")) {
-                    s = bufferedreader.readLine();
-                } else {
+                if (Main.useJline) {
                     s = bufferedreader.readLine(">", null);
+                } else {
+                    s = bufferedreader.readLine();
                 }
                 if (s != null) {
                     // CraftBukkit end

src/main/java/org/bukkit/craftbukkit/Main.java

@@ -12,7 +12,7 @@ import joptsimple.OptionSet;
 import net.minecraft.server.MinecraftServer;
 
 public class Main {
-    public static String jlineTerminalSetting;
+    public static boolean useJline = true;
 
     public static void main(String[] args) {
         // Todo: Installation script
@@ -88,11 +88,14 @@ public class Main {
             }
         } else {
             try {
+                useJline = !"jline.UnsupportedTerminal".equals(System.getProperty("jline.terminal"));
+                
                 if (options.has("nojline")) {
                     System.setProperty("jline.terminal", "jline.UnsupportedTerminal");
                     System.setProperty("user.language", "en");
+                    useJline = false;
                 }
-                jlineTerminalSetting = System.getProperty("jline.terminal");
+
                 MinecraftServer.main(options);
             } catch (Throwable t) {
                 t.printStackTrace();

src/main/java/org/bukkit/craftbukkit/util/TerminalConsoleHandler.java

@@ -5,6 +5,7 @@ import java.util.logging.ConsoleHandler;
 import java.util.logging.Level;
 import java.util.logging.Logger;
 import jline.ConsoleReader;
+import org.bukkit.craftbukkit.Main;
 
 public class TerminalConsoleHandler extends ConsoleHandler {
     private final ConsoleReader reader;
@@ -17,6 +18,7 @@ public class TerminalConsoleHandler extends ConsoleHandler {
     @Override
     public synchronized void flush() {
         try {
+            if (Main.useJline) {
                 reader.printString(ConsoleReader.RESET_LINE + "");
                 reader.flushConsole();
                 super.flush();
@@ -26,6 +28,9 @@ public class TerminalConsoleHandler extends ConsoleHandler {
                     reader.getCursorBuffer().clearBuffer();
                 }
                 reader.flushConsole();
+            } else {
+                super.flush();
+            }
         } catch (IOException ex) {
             Logger.getLogger(TerminalConsoleHandler.class.getName()).log(Level.SEVERE, null, ex);
         }