I'm currently creating a plugin system (My first attempt), looking at other peoples code I'm trying to piece together my own classloader and get the plugins loaded from a directory (These will be class files)
My problem is that whenever I attempt to load the class with my classloader, any imports in the plugin referencing the program are not found by the classloader. (ie: MyClass extends Plugin, com.mgmc.plugins noclassdeffound) Different namespace?
Some sample code: Classloader:
/* * To change this template, choose Tools | Templates * and open the template in the editor. */ package com.mcgm.game.provider; import com.mcgm.utils.Misc; import com.mcgm.utils.Paths; import java.awt.AWTPermission; import java.io.*; import java.net.MalformedURLException; import java.net.SocketPermission; import java.net.URL; import java.security.CodeSigner; import java.security.CodeSource; import java.security.Permissions; import java.security.ProtectionDomain; import java.util.PropertyPermission; import java.util.logging.Level; import java.util.logging.Logger; /** * * @author Tom */ public class GameClassLoader extends ClassLoader { private final ProtectionDomain domain; private final URL base; public GameClassLoader(final URL url) { base = url; final CodeSource codeSource = new CodeSource(base, (CodeSigner[]) null); domain = new ProtectionDomain(codeSource, getPermissions()); } public void loadGames() { for (File f : Paths.compiledFolder.listFiles()) { try { Class c = loadClass(f.getPath()); Misc.outPrint(c.getName()); } catch (ClassNotFoundException ex) { Logger.getLogger(GameClassLoader.class.getName()).log(Level.SEVERE, null, ex); } } } private Permissions getPermissions() { final Permissions ps = new Permissions(); ps.add(new AWTPermission("accessEventQueue")); ps.add(new PropertyPermission("user.home", "read")); ps.add(new PropertyPermission("java.vendor", "read")); ps.add(new PropertyPermission("java.version", "read")); ps.add(new PropertyPermission("os.name", "read")); ps.add(new PropertyPermission("os.arch", "read")); ps.add(new PropertyPermission("os.version", "read")); ps.add(new SocketPermission("*", "resolve")); ps.add(new FilePermission(Paths.compiledFolder.getPath(), "read,write,delete")); ps.setReadOnly(); return ps; } @Override @SuppressWarnings("rawtypes") public Class<?> loadClass(final String name, final boolean resolve) throws ClassNotFoundException { Class clazz = findLoadedClass(name); if (clazz == null) { try { byte[] bytes = loadClassData(name); clazz = defineClass(name, bytes, 0, bytes.length, domain); if (resolve) { resolveClass(clazz); } } catch (final Exception e) { clazz = super.loadClass(name, resolve); } } return clazz; } public byte[] loadClassData(final String name) { try { final InputStream in = getResourceAsStream(name.replace('.', '/') + ".class"); final byte[] buffer = new byte[4096]; final ByteArrayOutputStream out = new ByteArrayOutputStream(); int n; while ((n = in.read(buffer, 0, 4096)) != -1) { out.write(buffer, 0, n); } return out.toByteArray(); } catch (IOException ex) { Logger.getLogger(GameClassLoader.class.getName()).log(Level.SEVERE, null, ex); } return null; } @Override public URL getResource(final String name) { try { return new URL(base, name); } catch (final MalformedURLException e) { return null; } } @Override public InputStream getResourceAsStream(final String name) { try { return new URL(base, name).openStream(); } catch (final IOException e) { return null; } } } The Plugin I am loading: (The annotation isn't found either)
import com.mcgm.GameInfo; import com.mcgm.game.Minigame; @GameInfo(name = "RandomGame", description = "A really long and boring game.", authors = {"Tom", "Is", "The", "Greatest"}, version = 0.1, maxPlayers = 100, teamBased = false, teamAmount = -1, PvP = false) public class game extends Minigame { } How I'm calling the class to be loaded:
GameClassLoader classLoader = new GameClassLoader(Paths.compiledFolder.toURI().toURL()); classLoader.loadClass("game", true); I figure this is trivial for those that know what they're doing!
