I challenge Modification Development,but Minecraft can't run in Eclipse.
WARNING: An illegal reflective access operation has occurredWARNING: An illegal reflective access operation has occurred
WARNING: Illegal reflective access by GradleStart (file:/C:/Users/tokot/.gradle/caches/minecraft/net/minecraftforge/forge/1.7.10-10.13.4.1558-1.7.10/start/) to field java.lang.ClassLoader.sys_paths
WARNING: Please consider reporting this to the maintainers of GradleStartWARNING: Use --illegal-access=warn to enable warnings of further illegal reflective access operations
WARNING: All illegal access operations will be denied in a future release
[00:19:31] [main/INFO] [GradleStart]: Extra: 
Exception in thread "main" java.lang.ClassCastException: class jdk.internal.loader.ClassLoaders$AppClassLoader cannot be cast to class java.net.URLClassLoader (jdk.internal.loader.ClassLoaders$AppClassLoader and java.net.URLClassLoader are in module java.base of loader 'bootstrap') at net.minecraftforge.gradle.GradleStartCommon.searchCoremods(Unknown Source) at net.minecraftforge.gradle.GradleStartCommon.launch(Unknown Source) at GradleStart.main(Unknown Source)
Are you using Java 9 or later? You have to use Java 8 to make mods, as well as run them, due to issues with newer Java versions (FWIW, the launcher ships with Java 8 partly for this reason, though vanilla itself runs without any issues. mods often have trouble due to various bugs in Forge and/or mods using reflection and similar "hacky" methods to modify code, which is technically a security risk since they modify code at will, even if not with harmful intent):
https://www.reddit.com/r/feedthebeast/comments/764jzf/modders_java_9_any_insights/ (even if they do add support for newer Java versions they will likely never backport the fixes to 1.7.10; they did backport a fix for Java 8 to 1.6.4 but 1.7.10 is extremely old by now, much older than 1.6.4 was at the time, though the community made patches for it before Forge patched it. Either way, this is for running the game itself, not developing the mods).