Adding Libraries To Plugin

I am making a plugin that uses web input so I need it to scrape the webpage text. How can I make the plugin work on bukkit with the Jsoup libraries? http://jsoup.org

 

you simply add the jar in your plugin jar

 

Then it fires errors in the bukkit console

 

which errors ?

 

ClassDefNotFoundException or ClassNotFoundException probably

 

You need to add the jar to the classpath. That works with adding the key Class-Path: path/yourjar.jar into the MANIFEST.MF file in META-INF of your jar. http://docs.oracle.com/javase/tutorial/deployment/jar/manifestindex.html

 

bukkit wont read the mainfest

 

But the system classloader!

 

The issue is that the classes are present at build time, but not at run time. You need to package the library in your jar and it should work. If you're using eclipse, a plugin like "FatJar" can do that for you.

 

So for me it works fine with manifest files. It is also supported by apache ant. Jar's generated by FatJar etc. will fail too if you do classloading things at runtime... so it doesn't matter. If you want to be safe that every class is loaded by the classloader you should check that every path, which contains jar's / classes is in the classpath while booting your app/plugin/etc.

 

The classes have to be physically there for them to work, that's why Library plugins (Sync, PatPeter's SQL lib) have to be in the plugins folder (the bukkit classloader will have loaded them before your plugin) or packaged in your jar. This is the same, except since the lib he is trying to use isn't a plugin also, he needs to package it in his jar.

 

Just to bring attention to the wiki, http://wiki.bukkit.org/Using_External_Libraries_with_Plugins

 

EnvisionRed, @ all Sure there are many ways but it's not the common way. Because the classloader will load everything from all jar's. With this way you dont have the chance to load them on the fly. I think the biggest problem is that many people just read one two pages of the examples stuff, call themself a java programmer and fail with the easiest problems. There are alot of examples ( including the SUN/Oracle API ) and books ( with more than 300 pages!! ) to bring you up to the level of a professional. This language is not like making a Website with HTML. I would be happy if many would read this and spiritualize this topic to get the feeling that programming is nothing like baking rolls in 5 min in the oven, at all.