Java读写文件通用格式

String path = "I:\\";
File file = new File(path + "user_id_pair.txt");
FileReader reader = null;
BufferedReader br = null;
try {
reader = new FileReader(file);
br = new BufferedReader(reader);
String str = null;
int cnt=0;
while ((str = br.readLine()) != null) {
System.out.println(str);getClass();
cnt++;
}
System.out.println("end!"+cnt);

}
catch (Exception e) {
// TODO: handle exception
e.printStackTrace();
}
finally {
if (br != null) {
try {
br.close();
}
catch (Exception e2) {
// TODO: handle exception
e2.printStackTrace();
}
}
if (reader != null) {
try {
reader.close();
}
catch (Exception e2) {
// TODO: handle exception
e2.printStackTrace();
}
}
}

FileWriter fw = null;
BufferedWriter bw = null;
PrintWriter pw = null;// "J:\\user_id_pair.txt"
try {
fw = new FileWriter(new File(fileName), true);
bw = new BufferedWriter(fw);
pw = new PrintWriter(bw);
pw.write(content);
}
catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
finally {
if (pw != null) {
pw.close();
}
if (bw != null) {
try {
bw.close();
}
catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
if (fw != null) {
try {
fw.close();
}
catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}