清單類在包的子目錄

Question

我不知道如果我在這裏使用的是正確的術語..但如果我的包的名稱設置如下：

com.example.fungame 
    -ClassA 
    -ClassB 
    -com.example.fungame.sprite 
     -ClassC 
     -ClassD 

我如何編程方式獲得一個數組（一個Class[]我猜）在.sprite子目錄中的所有類？

Answer 1

試試這個方法：

public static Class[] getClasses(String pckgname) throws ClassNotFoundException { 
    ArrayList classes=new ArrayList(); 
    File directory = null; 
    try { 
     directory = new File(Thread.currentThread().getContextClassLoader().getResource(pckgname.replace('.', '/')).getFile()); 
    } catch(NullPointerException x) { 
     throw new ClassNotFoundException(pckgname + " does not appear to be a valid package"); 
    } 
    if (directory.exists()) { 
     // Get the list of the files contained in the package 
     String[] files = directory.list(); 
     for (int i = 0; i < files.length; i++) { 
      // we are only interested in .class files 
      if(files[i].endsWith(".class")) { 
       // removes the .class extension 
       try { 
        Class cl = Class.forName(pckgname + '.' + files[i].substring(0, files[i].length() - 6)); 
        classes.add(cl); 
       } catch (ClassNotFoundException ex) { 
       } 
      } 
     } 
    } else { 
     throw new ClassNotFoundException(pckgname + " does not appear to be a valid package"); 
    } 
Class[] classesA = new Class[classes.size()]; 
classes.toArray(classesA); 
return classesA; 
}