Hi

I have downloaded latest forge build forge-1.7.10-10.13.0.1208-src.zip

i type in windows 7 console:

gradlew setupDecompWorkspace
gradlew eclipse

No errors are arise.

Next, i run MC client from eclipse kepler and get this:

[14:05:46] [main/INFO] [GradleStart]: No arguments specified, assuming client.
[14:05:46] [main/INFO] [GradleStart]: Extra: []
[14:05:46] [main/INFO] [GradleStart]: Running with arguments: [--userProperties, {}, --assetsDir, C:/Users/RAIN/.gradle/caches/minecraft/assets, --assetIndex, 1.7.10, --accessToken, {REDACTED}, --version, 1.7.10, --tweakClass, cpw.mods.fml.common.launcher.FMLTweaker, --username, ForgeDevName]
[14:05:46] [main/INFO] [LaunchWrapper]: Loading tweak class name cpw.mods.fml.common.launcher.FMLTweaker
[14:05:46] [main/INFO] [LaunchWrapper]: Using primary tweak class name cpw.mods.fml.common.launcher.FMLTweaker
[14:05:46] [main/INFO] [LaunchWrapper]: Calling tweak class cpw.mods.fml.common.launcher.FMLTweaker
[14:05:46] [main/INFO] [FML]: Forge Mod Loader version 7.10.25.1208 for Minecraft 1.7.10 loading
[14:05:46] [main/INFO] [FML]: Java is Java HotSpot(TM) Client VM, version 1.8.0_20, running on Windows 7:x86:6.1, installed at C:\Program Files (x86)\Java\jre1.8.0_20
[14:05:46] [main/INFO] [FML]: Managed to load a deobfuscated Minecraft name- we are in a deobfuscated environment. Skipping runtime deobfuscation
[14:05:46] [main/INFO] [LaunchWrapper]: Loading tweak class name cpw.mods.fml.common.launcher.FMLInjectionAndSortingTweaker
[14:05:46] [main/INFO] [LaunchWrapper]: Loading tweak class name cpw.mods.fml.common.launcher.FMLDeobfTweaker
[14:05:46] [main/INFO] [LaunchWrapper]: Calling tweak class cpw.mods.fml.common.launcher.FMLInjectionAndSortingTweaker
[14:05:46] [main/ERROR] [LaunchWrapper]: Unable to launch
java.util.ConcurrentModificationException
at java.util.ArrayList$Itr.checkForComodification(Unknown Source) ~[?:1.8.0_20]
at java.util.ArrayList$Itr.remove(Unknown Source) ~[?:1.8.0_20]
at net.minecraft.launchwrapper.Launch.launch(Launch.java:117) [launchwrapper-1.9.jar:?]
at net.minecraft.launchwrapper.Launch.main(Launch.java:28) [launchwrapper-1.9.jar:?]
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[?:1.8.0_20]
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) ~[?:1.8.0_20]
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) ~[?:1.8.0_20]
at java.lang.reflect.Method.invoke(Unknown Source) ~[?:1.8.0_20]
at GradleStart.bounce(GradleStart.java:107) [start/:?]
at GradleStart.startClient(GradleStart.java:100) [start/:?]
at GradleStart.main(GradleStart.java:55) [start/:?]
Exception in thread "main" java.lang.ArrayIndexOutOfBoundsException: 0
at GradleStart.main(GradleStart.java:59)
Java HotSpot(TM) Client VM warning: Using incremental CMS is deprecated and will likely be removed in a future release

What is wrong?

The same thing as for every other person not being able to start minecraft forge.

Use Java 7. Not 8.

Can we just tell diesieben to make the header of the sub-forum Modder Support "If you are using Java 8, switch to Java 7, because if that's the case when you give us an error log, we won't help you." or something like that? Because the amount of people saying I HAVE A PROBLEM and then having their problem solved with a simple "Use Java 7 noob" is getting ridiculous.

Can we just tell diesieben to make the header of the sub-forum Modder Support "If you are using Java 8, switch to Java 7, because if that's the case when you give us an error log, we won't help you." or something like that? Because the amount of people saying I HAVE A PROBLEM and then having their problem solved with a simple "Use Java 7 noob" is getting ridiculous.

 

Questions such as those are very common in any programming board(or any board handling any topic for which you have to learn things for that matter). Any such action would not really help.

For one the foruminfo says this isn't a java tutorial yet how many people ask questions that would be easily solved if they knew more than 'first week OOP introduction' level java.

So I believe that, in the end, if you want to help people by answering questions on forums you will, and have to be always confronted with questions of very low level. That's simply how it works and unless beginners suddenly realise that they should read the errorlogs, use google optimally and use their brain they'll keep coming(and everyone knows that won't happen).

I guess you could say it is part of 'the job'.

 

Disclaimer: Reading the above can be harmful for your health if you are a budding programmer.

I like how you put the disclaimer at the end.

Thanks, problem solved. I was use wrong Java version.