How to add objects to HashSet from file using ObjectInputStream?
0
I have an empty file.txt with users and I am using ObjectOutputStream for write object into file after that I want to add this element into HashSet. How can I do it?
This is my method for add element:
Set<User> users = new HashSet<User>();
try {
Scanner scanner = new Scanner(file);
while (scanner.hasNext()){
String line = scanner.nextLine();
Scanner lineScanner = new Scanner(line);
lineScanner.useDelimiter("\|");
String name = lineScanner.next();
String password = lineScanner.next();
String email = lineScanner.next();
String nameSurname = lineScanner.next();
User user = new User(name, password, email, nameSurname);
users.add(user);
java io set
asked Nov 23 '18 at 11:01
Far112Far112
1
add a comment |
0
I have an empty file.txt with users and I am using ObjectOutputStream for write object into file after that I want to add this element into HashSet. How can I do it?
This is my method for add element:
Set<User> users = new HashSet<User>();
try {
Scanner scanner = new Scanner(file);
while (scanner.hasNext()){
String line = scanner.nextLine();
Scanner lineScanner = new Scanner(line);
lineScanner.useDelimiter("\|");
String name = lineScanner.next();
String password = lineScanner.next();
String email = lineScanner.next();
String nameSurname = lineScanner.next();
User user = new User(name, password, email, nameSurname);
users.add(user);
java io set
asked Nov 23 '18 at 11:01
Far112Far112
1
You rewrite the HashSet again to your file (which is not a txt file, but a binary file), to overwrite the old serialized HashSet by the new one
– JB Nizet
Nov 23 '18 at 11:05
add a comment |
0
0
0
I have an empty file.txt with users and I am using ObjectOutputStream for write object into file after that I want to add this element into HashSet. How can I do it?
This is my method for add element:
Set<User> users = new HashSet<User>();
try {
Scanner scanner = new Scanner(file);
while (scanner.hasNext()){
String line = scanner.nextLine();
Scanner lineScanner = new Scanner(line);
lineScanner.useDelimiter("\|");
String name = lineScanner.next();
String password = lineScanner.next();
String email = lineScanner.next();
String nameSurname = lineScanner.next();
User user = new User(name, password, email, nameSurname);
users.add(user);
java io set
asked Nov 23 '18 at 11:01
Far112Far112
1
I have an empty file.txt with users and I am using ObjectOutputStream for write object into file after that I want to add this element into HashSet. How can I do it?
This is my method for add element:
Set<User> users = new HashSet<User>();
try {
Scanner scanner = new Scanner(file);
while (scanner.hasNext()){
String line = scanner.nextLine();
Scanner lineScanner = new Scanner(line);
lineScanner.useDelimiter("\|");
String name = lineScanner.next();
String password = lineScanner.next();
String email = lineScanner.next();
String nameSurname = lineScanner.next();
User user = new User(name, password, email, nameSurname);
users.add(user);
java io set
java io set
asked Nov 23 '18 at 11:01
Far112Far112
1
asked Nov 23 '18 at 11:01
Far112Far112
1
asked Nov 23 '18 at 11:01
Far112Far112
1
asked Nov 23 '18 at 11:01
Far112Far112
1
asked Nov 23 '18 at 11:01
Far112Far112
1
1
You rewrite the HashSet again to your file (which is not a txt file, but a binary file), to overwrite the old serialized HashSet by the new one
– JB Nizet
Nov 23 '18 at 11:05
add a comment |
You rewrite the HashSet again to your file (which is not a txt file, but a binary file), to overwrite the old serialized HashSet by the new one
– JB Nizet
Nov 23 '18 at 11:05
You rewrite the HashSet again to your file (which is not a txt file, but a binary file), to overwrite the old serialized HashSet by the new one
– JB Nizet
Nov 23 '18 at 11:05
You rewrite the HashSet again to your file (which is not a txt file, but a binary file), to overwrite the old serialized HashSet by the new one
– JB Nizet
Nov 23 '18 at 11:05
add a comment |
0
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You rewrite the HashSet again to your file (which is not a txt file, but a binary file), to overwrite the old serialized HashSet by the new one
– JB Nizet
Nov 23 '18 at 11:05