[NOT SOLVED] Change existing line in minecraft.java

[Abbas369]

So I Want to change a line in minecraft.java to another line.How do I do it with forge mod?

[Abbas369]

Minecraft has this line:

skinUrl = (new StringBuilder()).append("some url").append(s).append(".png").toString();

 

So i want to change some url to my own website,and will tell people to use this mod so they can get skins from my own site