Is there a more proper and cleaner way/framework for creating classes(not modifying) at run time in JAVA?

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Java

In my Application a User can tell the fields he wants for a CLASS. Those parameters are then concatenated using StringBuilder and I have something like this at the end.

String classname = "MyTestClassTest";
StringBuilder sourceCode = new StringBuilder();
//First Create Class MyTestClassTest.
String classname = "MyTestClassTest";
sourceCode.append("public class ");
sourceCode.append(classname);
sourceCode.append(" implements java.io.Serializable  {");
sourceCode.append("public String testName");
sourceCode.append(";");
sourceCode.append("public int testNumber");
sourceCode.append(";");
sourceCode.append("public String toString() { return ");
sourceCode.append("\"NAME: \"");
sourceCode.append("+");
sourceCode.append("testName");
sourceCode.append(";");
sourceCode.append("}");
sourceCode.append("}");


CreateRuntimeClass codeExecuted = new CreateRuntimeClass(classname ,codeToExecute.toString() );
codeExecuted.createFileAndUpdateClassPath();

Then I use JavaCompiler to execute this code and a new CLASS is created.
Is there any better way to create new classes at runtime?
And does my way contains any issues?
Or any suggestion how I can improve my logic?
And does the byte code generated from compiling the code, is appended to the classpath, or how does it work?

What I have tried:

I am using the following code to generate classes at run time.

public class CreateRuntimeClass {

	
	private String className;
	private String sourceCode;
	private String fileLocation = "C://Users//UserName//workspace//JavaDataStructures//bin//";
	
	public CreateRuntimeClass (String className, String sourceCode) throws IOException, ClassNotFoundException, NoSuchMethodException, SecurityException, IllegalAccessException, IllegalArgumentException, InvocationTargetException, InstantiationException {
		
		this.className = className;
		this.sourceCode = sourceCode;
		//createFileAndUpdateClassPath();
		
	}
	
	
	public void createFileAndUpdateClassPath() throws IOException, ClassNotFoundException, NoSuchMethodException, SecurityException, IllegalAccessException, IllegalArgumentException, InvocationTargetException, InstantiationException{
		String fileName = this.fileLocation + className + ".java";
        File myFile = new File(fileName);
        // write the source code into the source file
        FileWriter writer = new FileWriter(myFile);
        writer.write("package datastructure;   "+ sourceCode);
        writer.close();
        
        // compile the source file
        JavaCompiler compiler = ToolProvider.getSystemJavaCompiler();
        StandardJavaFileManager fileManager = compiler.getStandardFileManager(null, null, null);
        File parentDirectory = myFile.getParentFile();
        fileManager.setLocation(StandardLocation.CLASS_OUTPUT, Arrays.asList(parentDirectory));
        Iterable<? extends JavaFileObject> compilationUnits = fileManager.getJavaFileObjectsFromFiles(Arrays.asList(myFile));
        compiler.getTask(null, fileManager, null, null, null, compilationUnits).call();
        fileManager.close();
        
        System.out.println(parentDirectory.toURI().toURL());  
        // load the compiled class
        URLClassLoader classLoader = URLClassLoader.newInstance(new URL[] { parentDirectory.toURI().toURL() });
        Class<?> helloClass = classLoader.loadClass("datastructure."+this.className);
        
        // call a method on the loaded class
        //Method helloMethod = helloClass.getDeclaredMethod("hello");
        //helloMethod.invoke(helloClass.newInstance());
        
        
		
	}
	
	
	
}