java 简单的读写文件

方便以后直接使用

    public void writeFileData(String fileName,String message){ 
        try{ 
            FileOutputStream fout =openFileOutput(fileName, MODE_PRIVATE);
            byte [] bytes = message.getBytes(); 
            fout.write(bytes); 
            fout.close(); 
        } 
            catch(Exception e){ 
            e.printStackTrace(); 
        } 
    }

    public String readFileData(String fileName){ 
        String res="always on = 0"; 

        String FILESPATH = getFilesDir().getPath() + "//"; 
        Log.d(TAG, "readFileData FILESPATH = " + FILESPATH);

        File alwaystxt = new File(FILESPATH + fileName);
        if(alwaystxt.exists()){
            try{ 
                FileInputStream fin = openFileInput(fileName); 
                int length = fin.available(); 
                byte [] buffer = new byte[length]; 
                fin.read(buffer);     
                res = EncodingUtils.getString(buffer, "UTF-8"); 
                fin.close();     
            } 
                catch(Exception e){ 
                e.printStackTrace(); 
            } 
            Log.d(TAG, "readFileData res = " + res);
        }
        else{
            Log.d(TAG, "readFileData file is not exists ");
        }
        return res; 
    }

write是保存一个带数字的字符串
read 是得到保存的字符串里面数字的值是多少

    String fileName = "always.txt";
    String filepath = "always.txt";

    String fileStrAlwaysOn_false = "always on = 0";
    String fileStrAlwaysOn_true = "always on = 1";

    writeFileData(fileName,fileStrAlwaysOn_true);
    getNumbers(readFileData(fileName));

    public int getNumbers(String content) {  
        Pattern pattern = Pattern.compile("\\d+");  
        Matcher matcher = pattern.matcher(content);  
        while (matcher.find()) {  
            Log.d(TAG, "getNumbers = " + matcher.group(0));
            String Number = matcher.group(0);  
            return Integer.parseInt(Number);
        }  
        return 0;  
    }