1.读取txt文件：

   txt文件：

         test1

         test2

   关键代码：

         InputStreamReader  inFile = new InputStreamReader(new FileInputStream(file));

         BufferedReader reader = new BufferedReader(inFile);

         String data = null;

         while((data = reader.readLine())!=null){

            System.out.println(data);

         }

2.读取csv文件（读取一组数据，需引入JavaCsv.jar包）:

      csv文件：

     

name	email	age	sex
test	123456@qq.com	23	W
test1	123456@qq.com	24	N
test2	123456@qq.com	25	W

      关键代码：

                  ArrayList<String[]>  arrayList = new ArrayList<String[]>(); 

                  CsvReader reader = new CsvReader(file);

                  reader.readHeaders();//跳过首行

                  while(reader.readRecord()){

                         arrayList.add(reader.getValues());

                  }

                 //输入内容

                 for(int i=0;i<arrayList.size();i++){

                     System.out.println("name:"+arrayList.get(i)[0]);

                     System.out.println("email:"+arrayList.get(i)[1]);

                     System.out.println("age:"+arrayList.get(i)[2]);

                     System.out.println("sex:"+arrayList.get(i)[3]);

                     System.out.println("--------------------");

                  }

3.xml文件（存储不规则数据）：

      xml文件：

             <?xml version="1.0" encoding="UTF-8" ?>

             <config>

                    <browser>firefox</browser>

                    <waitTime>20</waitTime> 

             </config>

     关键代码：

              SAXReader saxReader = new SAXReader();

              Document document = saxReader.read(file);