How do I turn a 1.10 plugin into a 1.8 plugin?

Just as the title says. I haven't really easily been able to find the 1.8 jar so I just temporarily used the 1.10.2 jar. So how do I turn my 1.10 plugin into a 1.8 one for my 1.8 server? I already have the jar for the server but where do I get the thing I need for making 1.8 plugins?

 

uh when I use the command on 1.8.9 it just says that "an internal or exteneral error has occured" or something along those lines. I just want to basically copy the code and put it in only using a 1.8 jar file

 

@dotJar1 Not much has changed, post the stacktrace from console in http://pastebin.com and we can support you on fixing the error.

 

most good plugins work in multiple versions but others that aren't programmed in that fail-safe way have to have a new java file installed.

 

If you have something like WinRAR, open the jar and find the .java classes. Use a spigot 1.8 dependency instead.

 

All I really need as of now is just to know where to get the 1.8 bukkit .jar file. That's really all I want.

 

@dotJar1
As long as the plugin only uses bukkits methods and imports, it should work on all versions of bukkit. If you start working in NMS or packets, then you will need to use Reflection in order to work on multiple versions.

If you have Build tools, you can use --rev 1.8 in order to get the 1.8 build.