**下面两张图是关于我删掉了lines = "";和加了lines += lines；的情况，最下面两行字还有具体解释，谢谢各位能浏览我的问题
**
问题出来return值上面，怎么能成功的return lines
package hotel1;
import java.io.BufferedReader;
import java.io.File;
import java.io.FileReader;
import java.io.IOException;
import java.util.ArrayList;
import hotel.CloseStreamMethod;
public class ImportData{
public ArrayList roomsLists = new ArrayList();
public static void main(String[] args) {
ImportData ip = new ImportData();
ip.importRooms();
}
public String importData(){
File src = new File("/Users/handsomeboy/eclipse-workspace/Coursework/src/hotel1/rooms.txt");
BufferedReader br = null;
String lines = null;
try {
br = new BufferedReader(new FileReader(src));
String line = null;
while((line = br.readLine()) != null) {
lines = "";
lines += line;
}
} catch (IOException e) {
e.printStackTrace();
} finally {
CloseStreamMethod csm = new CloseStreamMethod();
csm.close(br);
}
return lines;
}
public void importRooms() {
String[] content = importData().split("\n");
for (String row : content) {
if(row != null) {
String[] contents = row.split(",");
if (contents.length == 5) {
roomsLists.add(new Rooms(Integer.parseInt(contents[0]),
RoomType.valueOf(contents[1].toUpperCase()),
Double.parseDouble(contents[2]),
Integer.parseInt(contents[3]),contents[4]));
}
}
}
System.out.println(roomsLists);
}
}
输出内容:
[
RoomNumber: 301, Type: FAMILY, Price: 90.0, Capacity: 4, Facilities: own bathroom]
文本内容：
101,double,80.00,2,own bathroom
102,double,80.00,2,own bathroom
103,twin,70.00,2,shared bathroom
104,twin,70.00,2,shared bathroom
201,double,80.00,2,own bathroom
202,single,70.00,1,own bathroom
301,family,90.00,4,own bathroom
加了+号的一开始试过但是没有用，还有不加lines = "";不会打印出字符串，真的试了很多很多方法，但是改不出来，感谢各位能帮忙debug.
补充一下如果不加lines = "";的话就不能return lines，加了才能成功返回lines值，我也不知道什么，如果不加lines = ""; 打印imporData是可以成功答应所有的内容，
但是不能返回lines的值。
