public Class<?> findClass(String s) { try { byte[] bytes = loadClassData(s); return defineClass(s, bytes, 0, bytes.length); } catch (IOException ioe) { try { return super.loadClass(s); } catch (ClassNotFoundException ignore) { } ioe.printStackTrace(System.out); return null; } }
// Writes the program to a source file, compiles it, and runs it. private void compileAndRun(String fileName, String code) { // Exceptions here can pick and choose what font to use, as needed. // Exceptions thrown by the program, that cause the Playground to be unstable, should be in // blue. println("Deleting old temp files...", progErr); new File(fileName + ".java").delete(); new File(fileName + ".class").delete(); println("Creating source file...", progErr); file = new File(fileName + ".java"); println("Writing code to source file...", progErr); try { new FileWriter(file).append(code).close(); } catch (IOException i) { println("Had an IO Exception when trying to write the code. Stack trace:", error); i.printStackTrace(); return; // Exit on error } println("Compiling code...", progErr); // This should only ever be called if the JDK isn't installed. How you'd get here, I don't // know. if (compiler == null) { println("Fatal Error: JDK not installed. Go to java.sun.com and install.", error); return; } // Tries to compile. Success code is 0, so if something goes wrong, do stuff. int result = compiler.run( null, null, null, file .getAbsolutePath()); // Possibly add a new outputstream to parse through the // compiler errors if (result != 0) { displayLog(); println("Failed to compile.", error); return; // Return on error } println("Code compiled with 0 errors.", progErr); println("Attempting to run code...", progErr); run(fileName); }
// Creates a new thread, runs the program in that thread, and reports any errors as needed. private void run(String clazz) { try { // Makes sure the JVM resets if it's already running. if (JVMrunning) kill(); // Some String constants for java path and OS-specific separators. String separator = System.getProperty("file.separator"); String path = System.getProperty("java.home") + separator + "bin" + separator + "java"; // Tries to run compiled code. ProcessBuilder builder = new ProcessBuilder(path, clazz); // Should be good now! Everything past this is on you. Don't mess it up. println( "Build succeeded on " + java.util.Calendar.getInstance().getTime().toString(), progErr); println("~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~", progErr); JVM = builder.start(); // Note that as of right now, there is no support for input. Only output. Reader errorReader = new InputStreamReader(JVM.getErrorStream()); Reader outReader = new InputStreamReader(JVM.getInputStream()); // Writer inReader = new OutputStreamWriter(JVM.getOutputStream()); redirectErr = redirectIOStream(errorReader, err); redirectOut = redirectIOStream(outReader, out); // redirectIn = redirectIOStream(null, inReader); } catch (IOException e) { // JVM = builder.start() can throw this. println("IOException when running the JVM.", progErr); e.printStackTrace(); displayLog(); return; } }