Import java.io.inputstreamreader;

Open class question 1 {

/**

* Programming will replace the substring "word" in the text input from the keyboard with the string "world" and delete all substrings "this".

* Program requirements: The program should include comments, and should explain the function and usage of variables.

*/

Public static void main(String[] args) {

buffered reader reader = new buffered reader(new InputStreamReader(

system . in))；

String message = null// stores the string entered by the user.

Try {

while ((message = reader.readLine())！ = null) {

//Print the string before processing.

System.out.println ("input string:"+message ");

//replace word with world.

message = message . replace all(" word "，" world ")；

//Replace it with blank.

message = message . replace all(" this "，" ")；

//Print the processed string.

System.out.println ("After processing:"+message);

}

Catch (exception e) {

e . printstacktrace()；

System.out.println ("Exception occurred, program exits!" );

}

}

}