Make WorldConverter.convert() throws IOException in java

CHANGELOG.md

@@ -12,11 +12,12 @@ Click the link above to see the future.
 - [#84] Mappings for Minecraft Java Edition 1.15 items and blocks
 
 ### Changed
+- `WorldConverter.convert()` now throws `IOException` in java **(breaking change)**
+- Updated [Region-Manipulator to `2.0.0`][Region 2.0.0] from `1.1.0` **(breaking change)**
 - [#84] The source world must be optimized by Minecraft 1.15.2 now
 - If the converter finds an unmapped block 
   it will now be converted as 248:0 (minecraft:info_update) instead of 1:15 (stone with invalid data)
 - sweet_berries and shield are no longer replaced, they are obtainable in Nukkit 1.X now
-- Updated [Region-Manipulator to `2.0.0`][Region 2.0.0] from `1.1.0`.
 - Honey bottle and all banner patterns are no longer replaced, they aren't obtainable in Nukkit 1.X but 
 the server won't break if you have these items in your inventory anymore. 
 

src/main/kotlin/br/com/gamemods/j2nwc/WorldConverter.kt

@@ -4,6 +4,7 @@ import br.com.gamemods.j2nwc.internal.PostWorldConversionHook
 import br.com.gamemods.j2nwc.internal.convertLevelFile
 import br.com.gamemods.j2nwc.internal.convertRegionFile
 import java.io.File
+import java.io.IOException
 
 /**
  * A region position extracted from the region file name.
@@ -81,7 +82,10 @@ class WorldConverter(val from: File, val to: File) {
 
     /**
      * Executes the conversion in the current thread. Will take a while to complete.
+     *
+     * @throws IOException If an error occurs while loading or writing the files
      */
+    @Throws(IOException::class)
     fun convert() {
         check(to.isDirectory || to.mkdirs()) {
             "Failed to create the folder $to"