A.BufferedReader breader=new BufferedReader(new FileReader("abc.txt"));
B.PrintWriter out = new PrintWriter(new FileWriter(“abc.txt”),true);
C.FileInputStream fin = new FileInputStream(“abc.txt”);
D.OutputStreamWriter out = new OutputStreamWriter(new FileOutputStream(“abc.txt”));
A.try塊中可以有嵌套try塊
B.try塊后最多可以跟隨3個(gè)catch塊
C.try塊可以單獨(dú)存在