private void inputText() {
String str;
InputStreamReader isd = new InputStreamReader(System.in);
BufferedReader br = new BufferedReader(isd);
try {
do {
str = br.readLine().trim();
System.out.println("str="+str);
list.add(str);
}while(str!=null);
br.close();
isd.close();
}catch(IOException e) {
e.printStackTrace();
}
}直接键回车的时候应该str==null为什么我直接键回车的时候也跳不出循环啊
String str;
InputStreamReader isd = new InputStreamReader(System.in);
BufferedReader br = new BufferedReader(isd);
try {
do {
str = br.readLine().trim();
System.out.println("str="+str);
list.add(str);
}while(str!=null);
br.close();
isd.close();
}catch(IOException e) {
e.printStackTrace();
}
}直接键回车的时候应该str==null为什么我直接键回车的时候也跳不出循环啊
String str;
InputStreamReader isd = new InputStreamReader(System.in);
BufferedReader br = new BufferedReader(isd);
try {
do {
str = null;
str = br.readLine().trim();
System.out.println("str="+str);
list.add(str);
}while(str!=null);
br.close();
isd.close();
}catch(IOException e) {
e.printStackTrace();
}
}
import java.util.ArrayList;
import java.util.List;public class InputDemo { public static void main(String[] args) {
new InputDemo().inputText();
}
private List<String> inputText() {
List<String> list=new ArrayList<String>();
String str;
InputStreamReader isd = new InputStreamReader(System.in);
BufferedReader br = new BufferedReader(isd);
try {
while(!(str=br.readLine().trim()).equals("")){
System.out.println("str="+str);
list.add(str);
}
br.close();
isd.close();
}catch(IOException e) {
e.printStackTrace();
}
return list;
}
}
null是没有值,""是空值
null 和空值是两个概念!!