Add better asm support and lower the jar size

src/main/java/me/libraryaddict/disguise/utilities/reflection/asm/Asm14.java

@@ -1,6 +1,6 @@
 package me.libraryaddict.disguise.utilities.reflection.asm;
 
-import org.objectweb.asm.*;
+import org.bukkit.craftbukkit.libs.org.objectweb.asm.*;
 
 import java.io.IOException;
 import java.lang.reflect.Field;

src/main/java/me/libraryaddict/disguise/utilities/reflection/asm/AsmDownloader.java

@@ -0,0 +1,81 @@
+package me.libraryaddict.disguise.utilities.reflection.asm;
+
+import lombok.AccessLevel;
+import lombok.Getter;
+import me.libraryaddict.disguise.LibsDisguises;
+import me.libraryaddict.disguise.utilities.reflection.NmsVersion;
+
+import java.io.BufferedInputStream;
+import java.io.File;
+import java.io.FileOutputStream;
+import java.io.IOException;
+import java.lang.reflect.Method;
+import java.net.URL;
+import java.net.URLClassLoader;
+
+/**
+ * Created by libraryaddict on 20/02/2020.
+ */
+@Getter(value = AccessLevel.PRIVATE)
+public class AsmDownloader {
+    //   private String urlToGrab = "https://repository.ow2.org/nexus/content/repositories/releases/org/ow2/asm/asm/7
+    //   .3" +
+    //          ".1/asm-7.3.1.jar";
+    /**
+     * Using maven
+     */
+    private String urlToGrab = "https://search.maven.org/remotecontent?filepath=org/ow2/asm/asm/7.3.1/asm-7.3.1.jar";
+    private File filePath = new File(LibsDisguises.getInstance().getDataFolder(), "libs/org-ow2-asm-7.3.1.jar");
+
+    public AsmDownloader() {
+        if (NmsVersion.v1_13.isSupported()) {
+            throw new IllegalStateException("Sorry, this shouldn't have been started!");
+        }
+
+        try {
+            Class.forName("org.objectweb.asm.ClassReader");
+            return;
+        }
+        catch (NoClassDefFoundError | ClassNotFoundException ex) {
+            // It doesn't exist, good! Lets load it!
+        }
+
+        if (!hasASM()) {
+            LibsDisguises.getInstance().getLogger().info("Downloading required library for 1.12 support!");
+
+            downloadASM();
+
+            LibsDisguises.getInstance().getLogger().info("Downloaded!");
+        }
+
+        try {
+            Method method = URLClassLoader.class.getDeclaredMethod("addURL", URL.class);
+            method.setAccessible(true);
+            method.invoke(getClass().getClassLoader(), filePath.toURI().toURL());
+        }
+        catch (Throwable t) {
+            t.printStackTrace();
+        }
+    }
+
+    private boolean hasASM() {
+        return filePath.exists();
+    }
+
+    private void downloadASM() {
+        filePath.getParentFile().mkdirs();
+
+        try (BufferedInputStream in = new BufferedInputStream(
+                new URL(getUrlToGrab()).openStream()); FileOutputStream fileOutputStream = new FileOutputStream(
+                getFilePath())) {
+            byte[] dataBuffer = new byte[1024];
+            int bytesRead;
+            while ((bytesRead = in.read(dataBuffer, 0, 1024)) != -1) {
+                fileOutputStream.write(dataBuffer, 0, bytesRead);
+            }
+        }
+        catch (IOException e) {
+            e.printStackTrace();
+        }
+    }
+}

src/main/java/me/libraryaddict/disguise/utilities/reflection/asm/WatcherSanitizer.java

@@ -23,6 +23,10 @@ public class WatcherSanitizer {
         if (NmsVersion.v1_14.isSupported()) {
             asm = new Asm14();
         } else {
+            if (!NmsVersion.v1_13.isSupported()) {
+                new AsmDownloader();
+            }
+
             asm = new Asm13();
         }