So today I decided to make a server so I could play my new survival games map with a few friends. I downloaded the .jar folder. I made a folder for the server and made the start.command file. I gave it permission to run and it wouldn't work. Originally it said the file could not acesses the .jar. I looked around and some people said to rename the .jar to just be minecraft_server.jar. After doing that my terminal said: Last login: Thu Jan 9 15:57:23 on ttys001
Kevin:~ Mine$ /Users/Mine/Desktop/THIS\ SERVER\ WILL\ WORK\!/start.command ; exit;
Exception in thread "main" java.lang.ExceptionInInitializerError
at org.apache.logging.log4j.util.PropertiesUtil.<init>(PropertiesUtil.java:71)
at org.apache.logging.log4j.util.PropertiesUtil.<clinit>(PropertiesUtil.java:31)
at org.apache.logging.log4j.status.StatusLogger.<clinit>(StatusLogger.java:48)
at org.apache.logging.log4j.LogManager.<clinit>(LogManager.java:44)
at net.minecraft.server.MinecraftServer.<clinit>(SourceFile:46)
Caused by: java.lang.NullPointerException
at org.apache.logging.log4j.util.ProviderUtil.<clinit>(ProviderUtil.java:70)
... 5 more
logout

[Process completed]

I am not skilled at all at programing and have no idea what that means. Can anyone help me?