Android中文件存储工具类

/**
 * 文件流保存数据
 */
public class FileUtils {
    /**
     *
     *  data 字符串数据
     *  context 上下文对象
     *  fileName 文件名称
     */
    public void savaData(String data , Context context,String fileName){
        try {
            FileOutputStream fileOutputStream = context.openFileOutput(fileName+".txt", Context.MODE_PRIVATE);
            BufferedWriter writer = new BufferedWriter(new OutputStreamWriter(fileOutputStream));
            fileOutputStream.write(data.getBytes());
            if(fileOutputStream!=null){
                writer.close();
            }
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }

    }

    /**
     *读取数据
     *  name表示文件名称
     *  context上下文对象
     */
    public String findData(String fileName ,Context context){
        File cacheDir = context.getFilesDir();;
        File file=new File(cacheDir,fileName+".txt");
        if(file.exists()){
            try {
                FileInputStream inputStream = context.openFileInput(fileName+".txt");
                BufferedReader reader=new BufferedReader(new InputStreamReader(inputStream));
                String str=null;
                StringBuffer stringBuffer=new StringBuffer();
                while ((str=reader.readLine())!=null){
                    stringBuffer.append(str);
                }
                return stringBuffer.toString();
            } catch (FileNotFoundException e) {
                e.printStackTrace();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
        return null;
    }
}

详细解释参考：

http://blog.csdn.net/zhaihaohao1/article/details/42495501