无法在java中加载多个类文件

import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;

public class MultiClassLoader extends ClassLoader {
    public Class<?> loadClassFromFile(String filePath) throws IOException {
        File file = new File(filePath);
        byte[] bytes = new byte[(int) file.length()];
        try (FileInputStream fis = new FileInputStream(file)) {
            fis.read(bytes);
        }
        return defineClass(null, bytes, 0, bytes.length);
    }

    public static void main(String[] args) throws IOException {
        MultiClassLoader classLoader = new MultiClassLoader();
        Class<?> class1 = classLoader.loadClassFromFile("path/to/Class1.class");
        Class<?> class2 = classLoader.loadClassFromFile("path/to/Class2.class");
        // 加载并使用class1和class2
    }
}