Je ne plus lancer Minecraft

Bonjour, je joue a Minecraft depuis maintenant 4ans et je ne peux plus lancer le jeu, ça marchais et quand je le démarre le 30/12/2015 à 17h27 , je vois ce code de lancement qui fait que mon Minecraft ne se lance plus :


30 dec. 17:27:03 net.minecraft.launchwrapper.LogWrapper log
INFO: Loading tweak class name optifine.OptiFineTweaker
30 dec. 17:27:03 net.minecraft.launchwrapper.LogWrapper log
INFO: Using primary tweak class name optifine.OptiFineTweaker
30 dec. 17:27:03 net.minecraft.launchwrapper.LogWrapper log
INFO: Calling tweak class optifine.OptiFineTweaker
OptiFineTweaker: acceptOptions
OptiFineTweaker: injectIntoClassLoader skipped, OptiFine is loaded as a library
OptiFineTweaker: getLaunchArguments
OptiFineTweaker: getLaunchTarget
30 dec. 17:27:03 net.minecraft.launchwrapper.LogWrapper log
INFO: Launching wrapped minecraft {net.minecraft.client.main.Main}
Completely ignored arguments: []
[17:27:03] [Client thread/INFO]: Setting user: HyroonBot
[17:27:03] [Client thread/INFO]: (Session ID is token:c1fab2e6e61947fe9a33210707f9dae3:d1681b66343f4c26b7ac69c39aac86b9)
30 dec. 17:27:03 net.minecraft.launchwrapper.LogWrapper log
GRAVE: Unable to launch
java.lang.reflect.InvocationTargetException
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at net.minecraft.launchwrapper.Launch.launch(Launch.java:131)
at net.minecraft.launchwrapper.Launch.main(Launch.java:27)
Caused by: java.lang.NullPointerException
at com.google.common.base.Preconditions.checkNotNull(Preconditions.java:213)
at com.google.common.collect.Lists$ReverseList.<init>(Lists.java:767)
at com.google.common.collect.Lists.reverse(Lists.java:759)
at lt.b(SourceFile:156)
at lt.<init>(SourceFile:43)
at net.minecraft.server.MinecraftServer.<init>(SourceFile:155)
at bpo.<init>(IntegratedServer.java:52)
at ave.<init>(SourceFile:293)
at net.minecraft.client.main.Main.main(SourceFile:124)
... 6 more