Class loader split into two files

Author: AtomicScience

javoc/class/classLoader.lua

@@ -0,0 +1,26 @@
+local javoc, fileClassLoader = require("umfal")("javoc")
+
+local debugPrint = javoc.util.debug.print
+
+---Loads a class from a file. Path is relative from classpath
+---@param file string           @ Name of the class to load
+---@param classpath string      @ Absolute path to the classes to load
+---@return table class          @ Loaded and parsed class file
+function fileClassLoader.load(file, classpath)
+	if not file:find(".class") then
+		file = file .. ".class"
+	end
+
+	local filePath = "" .. classpath .. file
+
+	debugPrint("Attempting to load class on path of " .. filePath)
+	local stream = io.open(filePath, "rb")
+
+	if not stream then
+		debugPrint("Failed to find the file or open it")
+		error("Class File not found!")
+	end
+
+	debugPrint("File stream created, loading class from it")
+	return javoc.class.streamClassLoader.load(stream)
+end

javoc/class/fileClassLoader.lua

@@ -0,0 +1,25 @@
+local javoc, streamClassLoader = require("umfal")("javoc")
+
+local debugPrint = javoc.util.debug.print
+
+---Loads a class from the stream - usually file, but not always
+---@param stream file_stream    @ Stream with class file
+---@return table class          @ Load`ed and parsed class file
+function streamClassLoader.load(stream)
+	local class = {}
+
+	if not javoc.class.subloaders.magicValue.check(stream) then
+		error("Class loading aborted: incorrect 'magic value'")
+	end
+
+	debugPrint("Correct 'magic value' is loaded")
+
+	class.version      = javoc.class.subloaders.version.load(stream)
+	class.constantPool = javoc.class.subloaders.constantPool.load(stream)
+	class.accessFlags  = javoc.class.subloaders.accessFlags.load(stream)
+	class.thisClass, class.superClass = javoc.class.subloaders.classNames.load(stream, class.constantPool)
+
+	debugPrint("Class " .. class.thisClass.name .. " loaded successfully")
+
+	return class
+end

javoc/class/streamClassLoader.lua

@@ -0,0 +1,11 @@
+local javoc, magicValue = require("umfal")("javoc")
+
+local debugPrint = javoc.util.debug.print
+local binaryUtils = javoc.util.binaryUtils
+
+function magicValue.check(stream)
+	debugPrint("Loading 'magic value' (0xCAFEBABE)")
+	local magicValue = binaryUtils.readU4(stream)
+
+	return (magicValue == 0xCAFEBABE)
+end