Java读写文件

%创建文件%
try {
File f = new File("F:/read");
if(!file.exists()){
f.mkdir();
}
File ff = new File(f,"demo.txt");
if(!ff.exists()){
ff.createNewFile();
}
%写文件%
FileWriter fw = new FileWriter("F:/read/demo.txt");
fw.write("sdfsa");
fw.close();
%读文件%
Char[] ch = new Char[1024];
FileReader fr = new FileReader("F:/read/demo.txt");
fr.read(ch);
System.out.printf("读取到的是:"+ch);
}catch(Exception e){

}