Java用尾递归遍历目录

public class TraverseFileDirectoryActivity extends Activity {
	private static final String TRAVERSE_DIRECTORY = "/sdcard/";
	
	private List<String> mFileList = new ArrayList<String>(); 
    
	/** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        
        // Begin to traverse directory
        File file = new File(TRAVERSE_DIRECTORY);
        List<File> fileList = new ArrayList<File>();
        fileList.add(file);
        getFilesRecursively(fileList);
        
        // Print out the result
        for(int i = 0; i < mFileList.size(); i++){
        	System.out.println(mFileList.get(i));
        }
    }
    
    private void getFilesRecursively(List<File> fileList){
    	List<File> directoryList = new ArrayList<File>();
    	
    	for (int i = 0; i < fileList.size(); i++){
    		if (fileList.get(i).isDirectory()){
    			directoryList.add(fileList.get(i));
    		}
    		else{
    			if (fileList.get(i).getName().toLowerCase().endsWith(".vcf")
    					&& fileList.get(i).canRead()){
    				mFileList.add(fileList.get(i).getName());
    			}
    		}
    	}
    	
    	if (directoryList.size() != 0){
    		getFilesRecursively(listFiles(directoryList));
    	}
    }
    
    private List<File> listFiles(List<File> directoryList){
    	List<File> fileList = new ArrayList<File>(); 
    	File[] files = null;
    	
    	for (int i = 0; i < directoryList.size(); i++){
    		files = directoryList.get(i).listFiles();
    		if (files != null){
    			fileList.addAll(Arrays.asList(files));
    		}
    	}
    	
    	return fileList;
    }
}