输入输出流：写入文件txt 读取文件txt

读取文本中的文字：

	//资费显示函数
	public void showDescription() {
		//用缓冲区读取文本文件
		FileReader fr = null;
        BufferedReader br = null;
        try {
            //创建一个FileReader对象
            fr = new FileReader("E:/嗖嗖移动大厅项目/套餐资费说明.txt");
            //创建一个BufferedReader对象
            br = new BufferedReader(fr);
            //读取一行数据
            String line = null;
            while((line = br.readLine()) != null){
                System.out.println(line);
            }
		} catch (FileNotFoundException e) {
			e.printStackTrace();
		}catch (IOException e) {
			e.printStackTrace();
		}finally {
			try {
				if(br != null) {
					br.close();
				}
				if(fr != null){
					fr.close();
				}
			} catch (IOException e) {
				 e.printStackTrace();
			}
		}
	}

写入文本：

	//打印消费详单
	public void printAmountDetail(String number) {
		MobileCard card=cards.get(number);
		Writer fileWriter = null;
		try {
                         //写入到consumes.txt文件中
			fileWriter = new FileWriter("E:/嗖嗖移动大厅项目/consumes.txt");
			 StringBuffer content = new StringBuffer("***********" + number + "消费记录************\n");
				int i=1;
				for(String s:card.getXiaofeitest()) {			
					content.append(s);//写入到文本之后
					i++;	
				}
				 fileWriter.write(content.toString());

	             fileWriter.flush();

	             System.out.println("消息记录打印完毕！");
		} catch (IOException e) {
			e.printStackTrace();
		}finally {
			try {

                fileWriter.close();

            } catch (IOException e) {

                e.printStackTrace();

            }
		}
	}