Add missing files

Signed-off-by: Francisco Solis <imfran@duck.com>

src/main/kotlin/xyz/theprogramsrc/simplecoreapi/global/module/ModuleClassLoader.kt

@@ -0,0 +1,105 @@
+package xyz.theprogramsrc.simplecoreapi.global.module
+
+import com.google.common.io.ByteStreams
+import java.io.File
+import java.net.URLClassLoader
+import java.security.CodeSource
+import java.util.concurrent.CopyOnWriteArraySet
+import java.util.jar.JarFile
+
+class ModuleClassLoader(
+    private val moduleDescription: ModuleDescription,
+    private val file: File
+): URLClassLoader(arrayOf(file.toURI().toURL())) {
+
+    companion object {
+        private val loaders = CopyOnWriteArraySet<ModuleClassLoader>()
+
+        init {
+            ClassLoader.registerAsParallelCapable()
+        }
+    }
+
+    private val jarFile = JarFile(file)
+    private val url = file.toURI().toURL()
+    private val manifest = jarFile.manifest
+    private var module: Module? = null
+
+    init {
+        loaders.add(this)
+    }
+
+    override fun loadClass(name: String, resolve: Boolean): Class<*> = loadClassInternally(name, resolve)
+
+    private fun loadClassInternally(name: String, resolve: Boolean, checkOther: Boolean = true): Class<*> {
+        try {
+            val result = super.loadClass(name, resolve)
+            if(checkOther || result.classLoader == this) {
+                return result
+            }
+        } catch (_: ClassNotFoundException) {}
+
+        if (checkOther) {
+            for (loader in loaders) {
+                if (loader != this) {
+                    try {
+                        return loader.loadClassInternally(name, resolve, false)
+                    } catch (_: ClassNotFoundException) {}
+                }
+            }
+        }
+
+        throw ClassNotFoundException(name)
+    }
+
+    override fun findClass(name: String): Class<*> {
+        val path = name.replace('.', '/').plus(".class")
+        val entry = jarFile.getJarEntry(path)
+
+        val classBytes = jarFile.getInputStream(entry).use {
+            ByteStreams.toByteArray(it)
+        }
+
+        val dot = name.lastIndexOf('.')
+        if(dot != -1) {
+            val pkgName = name.substring(0, dot)
+            if(getPackage(pkgName) == null) {
+                try {
+                    if(manifest != null) {
+                        definePackage(pkgName, manifest, url)
+                    } else {
+                        definePackage(pkgName, null, null, null, null, null, null, null)
+                    }
+                }catch (_: IllegalArgumentException) {
+                    if(getPackage(pkgName) == null) {
+                        throw IllegalStateException("Cannot find package $pkgName")
+                    }
+                }
+            }
+
+            val signers = entry.codeSigners
+            return defineClass(name, classBytes, 0, classBytes.size, CodeSource(url, signers))
+        }
+
+        return super.findClass(name)
+    }
+
+    override fun close() {
+        jarFile.use {
+            super.close()
+        }
+    }
+
+    fun init(module: Module) {
+        check(module.javaClass.classLoader == this) {
+            "Module class loader mismatch"
+        }
+
+        check(this.module == null) {
+            "Module already initialized"
+        }
+
+        this.module = module
+        module.init(this.file, this.moduleDescription)
+    }
+}