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Issues Serializing an ArrayList object containing other ArrayList objects

So I'm Serializing an ArrayList of ArrayLists essentially but I'm running into an issue. To be honest I'm still pretty new to Java, I've tried so many different methods to fix this as well as searched relentlessly on this site and have not been successful. I know that the way I word things may be hard to follow along or is confusing so I'll post my code here to see. Sorry in advance for all the code. SuperUsers has an arraylist of LoginInfo, PasswordKeeper has an Arraylist of SuperUsers, and the SuperUser arraylist gets serialized in PasswordKeeper. but any changes made to the LoginInfo arraylist do not save and i cannot figure out why. If anyone can help I would really Appreciate it. Thanks
public class PasswordKeeper{
private ArrayList<SuperUser> users;
private static Scanner keyboard = new Scanner(System.in);
public PasswordKeeper() {
users = new ArrayList();
}
public void login() {
try {
// reads in SuperUser arraylist
get();
} catch (EOFException a) {
System.out.println("You are the First User!");
} catch (IOException b) {
System.out.println(b);
} catch (ClassNotFoundException c) {
System.out.println(c);
}
boolean loopDisplay = true;
while (loopDisplay) {
existingUser = keyboard.next();
existingPass = keyboard.next();
SuperUser temp = new SuperUser(existingUser, existingPass);
System.out.println();
if (users.contains(temp)) {
// viewing superUser method
temp.display();
//saves after method call is over
try {
System.out.println("Saving.");
save(users);
} catch (IOException e) {
System.out.println(e);
}
}
}
//This happens if there is a new user
if(answer == 2){
SuperUser tempNew = null;
boolean cont = true;
String newUser;
String pass;
while(cont){
newUser = keyboard.nextLine();
System.out.println();
//System.out.println(users.size());
tempNew = new SuperUser(newUser, pass);
if(passValid(pass) == true){
if(makeSure(tempNew) == true){
System.out.println("Login Created!");
tempNew = new SuperUser(newUser, pass);
//actually being added to the arraylist
users.add(tempNew);
cont = false;
}
}
}
//SuperUser.display method
tempNew.display();
try{
System.out.println("Saving.");
save(users);
}catch(IOException e){
System.out.println(e);
}
}
}
}
//makeSure and passValid methods
public boolean makeSure(SuperUser user){
if(users.contains(user)){
return false;
}
return true;
}
public boolean passValid(String pass){
boolean passes = false;
String upper = "(.*[A-Z].*)";
String lower = "(.*[a-z].*)";
String numbers = "(.*[0-9].*)";
String special = "(.*[,~,!,#,#,$,%,^,&,*,(,),-,_,=,+,[,{,],},|,;,:,<,>,/,?].*$)";
if((pass.length()>15) || (pass.length() < 8)){
System.out.println("Entry must contain over 8 characters\n" +
"and less than 15.");
passes = false;
}if(!pass.matches(upper) || !pass.matches(lower)){
System.out.println("Entry must contain at least one uppercase and lowercase");
passes = false;
}if(!pass.matches(numbers)){
System.out.println("Password should contain atleast one number.");
passes = false;
}if(!pass.matches(special)){
System.out.println("Password should contain atleast one special character");
passes = false;
}else{
passes = true;
}
return passes;
//serializable methods
public void save(ArrayList<SuperUser> obj) throws IOException {
File file = new File("userInformation.dat");
FileOutputStream fileOut = new FileOutputStream(file, false);
BufferedOutputStream buffedOutput = new BufferedOutputStream(fileOut);
ObjectOutputStream out = new ObjectOutputStream(buffedOutput);
out.writeObject(obj);
out.close();
fileOut.close();
}
public ArrayList<SuperUser> get() throws IOException, ClassNotFoundException {
FileInputStream fileIn = new FileInputStream("userInformation.dat");
BufferedInputStream buffedInput = new BufferedInputStream(fileIn);
ObjectInputStream in = new ObjectInputStream(buffedInput);
users = (ArrayList<SuperUser>) in.readObject();
in.close();
fileIn.close();
return users;
}
public class SuperUser implements Serializable {
private String userName;
private String password;
private static Scanner keyboard = new Scanner(System.in);
private ArrayList<LoginInfo> info = new ArrayList();
public SuperUser(String name, String pass) {
userName = name;
password = pass;
}
public String getUser() {
return userName;
}
public void display() {
String next = keyboard.next();
//want to add data to LoginInfo arraylist
if (next.equalsIgnoreCase("add")) {
add();
} else if (next.equalsIgnoreCase("delete")) {
delete();
} else if (numberCheck(next)) {
int choice = (int) Integer.parseInt(next) - 1;
edit(choice);
//!!!! this: after doing this i lose whatever data i added
//to the LoginInfo arraylist, right after this the
//SuperUser arraylist gets saved. but the added data to
//loginInfo does not
} else if (next.equalsIgnoreCase("logout")) {
System.out.println(info.size());
}
}
public boolean numberCheck(String in) {
try {
Integer.parseInt(in);
} catch (NumberFormatException e) {
return false;
}
return true;
}
//method to add to the Arraylist
public void add() {
System.out.println("What is the website name?:");
String trash = keyboard.nextLine();
String webName = keyboard.nextLine();
System.out.println("The Username?:");
String webUsername = keyboard.nextLine();
System.out.println("The Password?:");
String webPass = keyboard.nextLine();
info.add(new LoginInfo(webUsername, webPass, webName));
System.out.println(info.size());
//method goes back to display
display();
}
}
}

Your problem is here
SuperUser temp = new SuperUser(existingUser, existingPass);
System.out.println();
if (users.contains(temp)) {
// viewing superUser method
temp.display();
You create a temporary object which with the username and password.
Your 'users.contains()' method returns true because '.equals()' is based on the username, however the 'temp' object is a different instance to that in the list.
So when you call 'temp.display()' it is not calling on an object in the list, so no data changes will save.
You need to find the existing object from the list for that user. I would suggest that you swap your list for a map keyed on username.

You have a list named users. Once you created new SuperUser instance (temp), you are checking that it belongs to this list (users.contains(temp), which is false of course - from where it will occur there?). If it have belonged, the method display would be called, which in turn would add LoginInfo to that SuperUser (add() call), but I bet in reality it doesn't happened.
Also, I see where you read from users (check whether new SuperUser instances belong there), I see where you overwrite it (during desealization) but I don't see adding any instance to there, which makes me think that it is always empty.
Are you sure that SuperUser contains any LoginInfo in its array list?

CSVReader does not check the whole file

I am trying to open a csv file using openCSV, iterate over every column and if the userID is different write a new JavaBean pair at the end of the file.
The problem is that the reader only checks the first column of my file and not the whole file. While created, the file contains only a header and nothing else. The program will check every column and if the sudoID is different it will write it to the file. If the sudoID in the first line is equal to the the one imported from my main class it will recognise it and not write it. But if this -same- sudoID is in the second row it will not recognise it and will write it again.
For instance, if my CSV looks like this it will work:
"Patient_id Pseudo_ID",
"32415","PAT106663926"
If it looks like this it will re-write the sudoID:
"Patient_id Pseudo_ID",
"32416","PAT104958880"
"32415","PAT106663926"
Thanks!
My Code:
public class CSVConnection {
#SuppressWarnings({ "deprecation", "resource", "rawtypes", "unchecked" })
public String getID(String sID,String pseudoID) throws IOException, CsvDataTypeMismatchException, CsvRequiredFieldEmptyException{
try {
CsvToBean csv = new CsvToBean();
String csvFilename = "CsvFile.csv";
Writer writer= new FileWriter(csvFilename,true);
CSVReader csvReader = new CSVReader(new FileReader(csvFilename),',','"',1);
ColumnPositionMappingStrategy strategy = new ColumnPositionMappingStrategy();
strategy.setType(PatientCSV.class);
String[] columns = new String[] {"patID","pseudoID"};
strategy.setColumnMapping(columns);
//Set column mapping strategy
StatefulBeanToCsv<PatientCSV> bc = new StatefulBeanToCsvBuilder<PatientCSV>(writer).withMappingStrategy(strategy).build();
List patList = csv.parse(strategy, csvReader);
for (Object patObj : patList) {
PatientCSV pat = (PatientCSV) patObj;
if(((PatientCSV) patObj).getPatID().equals(sID)){
return pat.getPseudoID();
}
else
{
PatientCSV pat1 = new PatientCSV();
pat1.setPatID(sID);
pat1.setPseudoID(pseudoID);
patList.add(pat1);
/*Find a way to import it to the CSV*/
bc.write(pat1);
writer.close();
return pseudoID;
}
}
} catch (FileNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return null;
}
public static void main(String [] args) throws IOException, CsvDataTypeMismatchException, CsvRequiredFieldEmptyException{
CSVConnection obj = new CSVConnection();
String sID="32415";
String pseudoID="PAT101830150";
obj.getID(sID,pseudoID);
}
}
and the Java Bean :
public class PatientCSV {
private String patID;
private String pseudoID;
public String getPatID() {
return patID;
}
public void setPatID(String patID) {
this.patID = patID;
}
public String getPseudoID() {
return pseudoID;
}
public void setPseudoID(String pseudoID) {
this.pseudoID = pseudoID;
}
public PatientCSV(String patID, String pseudoID) {
super();
this.patID = patID;
this.pseudoID = pseudoID;
}
public PatientCSV() {
super();
// TODO Auto-generated constructor stub
}
public String toString()
{
return "Patient [id=" + patID + ", pseudoID=" + pseudoID + "]";
}
}

Lets inspect your for loop
for (Object patObj : patList) {
PatientCSV pat = (PatientCSV) patObj;
if(((PatientCSV) patObj).getPatID().equals(sID)){
return pat.getPseudoID();
}
else
{
PatientCSV pat1 = new PatientCSV();
pat1.setPatID(sID);
pat1.setPseudoID(pseudoID);
patList.add(pat1);
/*Find a way to import it to the CSV*/
bc.write(pat1);
writer.close();
return pseudoID;
}
}
So in the case you mention it is not working as expected, meaning that the line that matches your input is the second line:
"Patient_id Pseudo_ID",
"32416","PAT104958880"
"32415","PAT106663926"
So you call: getID("32415", "PAT106663926")
What happens in your loop is:
You take the first element of your csv patients, the one with id: 32416,
check if it matches with the id given as input to your method, 32415.
It does not match so it goes to the else part. There it creates the new patient (with the same patID and pseudoID as the 2nd row of your csv) and stores it in the file.
So by now you should have 2 entries in your csv with the same data "32415","PAT106663926".
I think that this is the error, in your for loop you should check against all entries if there is a match, and then create the patient and store it to the csv.
An example:
PatientCSV foundPatient = null;
for (Object patObj : patList) {
PatientCSV pat = (PatientCSV) patObj;
if(((PatientCSV) patObj).getPatID().equals(sID)){
foundPatient = pat;
}
}
if (foundPatient == null) {
foundPatient = new PatientCSV();
foundPatient.setPatID(sID);
foundPatient.setPseudoID(pseudoID);
patList.add(foundPatient);
/*Find a way to import it to the CSV*/
bc.write(foundPatient);
writer.close();
}
return foundPatient.getPseudoID();
P.S. The above example is written very quickly, just to give you the idea what needs to be done.

read serializable custom object into file android

i am trying to record and reab back my list into file. It's working great until I restart my application. I am working with simulator (I don't have a real phone under Android)
Here is my function to record my class into a file :
public boolean writeRecordsToFile(String path, DummyContent object){
FileOutputStream fos;
ObjectOutputStream oos = null;
try {
fos = fileContext.openFileOutput(path, Context.MODE_PRIVATE);
oos = new ObjectOutputStream(fos);
oos.writeObject(object);
oos.close();
Log.d("fileManager", "Records write successfully");
return true;
} catch (Exception e) {
Log.e("fileManager", "Cant save records : " + e.getMessage());
return false;
}
finally {
if (oos != null)
try {
oos.close();
} catch (Exception e) {
Log.e("fileManager", "Error while closing stream "+e.getMessage());
}
}
}
Here is my reading Function :
public boolean readRecordsFromFile(String path){
FileInputStream fin;
ObjectInputStream ois=null;
try {
fin = fileContext.openFileInput(path);
ois = new ObjectInputStream(fin);
DummyContent records = (DummyContent) ois.readObject();
records.addItem("test", "test", "test");
ois.close();
Log.d("fileManager", "Records read successfully :\n" + records.toString());
Log.d("fileManager", "nbArticle found : " + String.valueOf(records.ITEMS.size()));
Log.d("fileManager", "article 0 title :\n" + records.ITEMS.get(0).content);
Log.d("fileManager", "article 10 title :\n" + records.ITEMS.get(10).content);
return true;
} catch (Exception e) {
Log.e("fileManager", "Cant read saved records : "+e.getMessage());
return false;
}
finally {
if (ois != null)
try {
ois.close();
} catch (Exception e) {
Log.e("fileManager", "Error in closing stream while reading records : "+e.getMessage());
}
}
}
and here is my class :
public class DummyContent implements Serializable {
/**
* An array of sample (dummy) items.
*/
public static List<DummyItem> ITEMS = new ArrayList<DummyItem>();
/**
* A map of sample (dummy) items, by ID.
*/
public static Map<String, DummyItem> ITEM_MAP = new HashMap<String, DummyItem>();
public void addItem(String first, String second, String third) {
DummyItem dummyItem = new DummyItem(first, second, third, android.R.drawable.ic_input_add);
ITEMS.add(dummyItem);
ITEM_MAP.put(dummyItem.id, dummyItem);
}
public void deleteAll() {
ITEMS = new ArrayList<DummyItem>();
ITEM_MAP = new HashMap<String, DummyItem>();
}
public void changeURL(Long index, String newURL) {
ITEMS.get(index.intValue()).url = newURL;
}
public void changeContent(Long index, String newContent) {
ITEMS.get(index.intValue()).contenu = newContent;
}
/**
* A dummy item representing a piece of content.
*/
public static class DummyItem {
public final String id;
public final String content;
public final String details;
public final int imageResource;
public String url;
public String contenu;
public DummyItem(String id, String content, String details, int imageResource) {
this.id = id;
this.content = content;
this.details = details;
this.imageResource = imageResource;
this.url = "";
this.contenu = "";
}
#Override
public String toString() {
return content;
}
}
}
Finally I read my file at the onCreate of my MainActivity (first activity at the lunching app) :
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
fileManager = new FileManager(this.getApplicationContext());
Log.d("Main", String.valueOf(fileManager.fileExist("Article.art")));
fileManager.readRecordsFromFile("Article.art"); /* Bug here : size of my array is empty but file's size is the same */
}
Here is my console return :
D/fileManager: size = 102
D/fileManager: Records read successfully :
D/fileManager: nbArticle found : 1 (because i add an item at the read
function) E/fileManager: Cant read saved records : Index: 10, Size: 1
I know it is working because when I write and read directly after the writting, I got all my items and I can read several times and I still got all items (this bug semms to be only present when I restart my application)
Maybe can I got help ?
Thanks !

The reason is very easy: You have declared some field as static, which are not covered by standard serialization: So, the contents of these fields were never written nor read from the file. That's why they "dissapeared" after a JVM restart.
Any field you want to be serialized/deserialized, you must declare it as instance member (not static).
See documentation on Serializable.

Java, passing values between classes

Ok so I'm a noob at Java and this just got me.
I have a button that calls a class in which some background code runs to check if the tape drive is online, offline or busy.
Button Code:
private void btnRunBckActionPerformed(java.awt.event.ActionEvent evt) {
// TODO add your handling code here:
btnRunBackup runBackupObject = new btnRunBackup();
runBackupObject.checkStatus();
lblRunBck.setText("Errors go here");
}
Then I have my separate class file btnRunBackup.
public class btnRunBackup{
public void checkStatus(){
/*
Here I simply create a tempfile and run some
linux commands via getRuntime and print the
output to the tempfile
Then I call my second method passing the
absolute file path of the tempfile
*/
this.statusControl(path);
}catch(IOException e){
e.printStackTrace();
public void statusControl(String param) throws FileNotFoundException, IOException{
/*
Here I use BufferedReader to go through the
tempfile and look for as series of 3
different strings.
I use a if else if statement for flow control
depending on what string was found.
string 1 will call a new Jframe
if string 2, 3 or none of them are found the
is where I am stuck at
}
}
I want to return a String value back to btnRunBckActionPerformed().
The reason is lblRunBck will initially show no text at all but for instance the user clicks on the button and the resource happens to be busy then i want to run lblRunBck.setText(param); on lblRunBck while refusing the user permission to continue
private void btnRunBckActionPerformed(java.awt.event.ActionEvent evt) {
// TODO add your handling code here:
String text;
btnRunBackup runBackupObject = new btnRunBackup();
runBackupObject.checkStatus();
lblRunBck.setText("Errors go here");
}
here is my btnRunBackup class
public class btnRunBackup {
private String s;
public void checkStatus() {
String s, path = null;
Process p;
try{//try1
//create a temp file named tempfilexxx.tmp
File temp = File.createTempFile("tempfile", ".tmp");
//get file path
path = temp.getAbsolutePath();
System.out.println("checkStatus: " + path);
//write to tempfilexxx.tmp
BufferedWriter bw = new BufferedWriter(new FileWriter(temp));
try{// try2
//set p = to the content of ls home
p = Runtime.getRuntime().exec("ls /home | grep ariel");
BufferedReader br = new BufferedReader(
new InputStreamReader(p.getInputStream()));
//write content of p to tempfilexxx.tmp line by line
while ((s = br.readLine()) != null)
bw.write(s + "\n");
//close BufferedReader
br.close();
}catch (Exception e){} //END OF try2
//close BufferedWriter
bw.close();
/*
Now that we ran the 'mt -f /dev/nst0 status command under home we
will filter for one of the following strings
(for testing we will use ls -la /home and filter for ariel)
We will do this by calling the checkStatus method
*/
this.statusControl(path);
}catch(IOException e){
e.printStackTrace();
}// END OF try1
}// END OF listDir
//throws FileNotFoundException for bufferedReader if file not found
public void statusControl(String param) throws FileNotFoundException, IOException{
/*
On production code there will be 4 possible conditions:
1. ONLINE - ready to write (currently we will use ariel)
2. DR_OPEN - no tape available
3. /dev/nst0: Device or resource busy - resource bussy
4. If other than stated above give error 1000
*/
System.out.println("statusControl: " + param);
String ONLINE = "arielvz",
OPEN = "DR_OPEN",
BUSSY = "Device or resource busy",
sCurrentLine;
//Scan file line by line for one of the above options
BufferedReader br = new BufferedReader(new FileReader(param));
while ((sCurrentLine = br.readLine()) != null){
//Tape is online and ready for writing
if (sCurrentLine.contains(ONLINE)){
System.out.println("found ariel");
}
//There is no tape in the tape drive
else if (sCurrentLine.contains(OPEN)){
//lblRunBck should tell the user to put a tape in the drive
System.out.println("No tap in tape drive");
}
else if (sCurrentLine.contains(BUSSY)){
//lblRunBck should notify user that the resource is in use
System.out.println("Device or resource bussy");
}
else{
//Something unexpected happend
System.out.println("Error 1001: Please notify Administrator");
}
}
}//END OF statusControl
public String returnHandler(String param){
return param;
}
}
Maby This will make it more clear

If you want checkStatus to return a status, then do not make it returning nothing (a void function)
public class btnRunBackup {
private String s;
public void checkStatus() {
but make it returning error as a String like:
public class btnRunBackup {
private String s;
public String checkStatus() {
String error = null; // by default no error
... do whatever you need to find out the error
....
error = "error is: xxx ";
return error; // return null (no error ) or what you found
}
change you logic in you calling code to display what error have been returned by checkStatus
private void btnRunBckActionPerformed(java.awt.event.ActionEvent evt)
{
// TODO add your handling code here:
String error;
btnRunBackup runBackupObject = new btnRunBackup();
error = runBackupObject.checkStatus();
lblRunBck.setText(error == null ? "No error" : error);
}

Insert string in clipboard without lost formatted text / style

I need to insert a string at the beginning of the clipboard without losing inline formatting of text containing the same. Currently this is not happening in my code!
public String getClipboard()
{
Transferable t = Toolkit.getDefaultToolkit().getSystemClipboard().getContents(null);
try
{
if (t != null && t.isDataFlavorSupported(DataFlavor.stringFlavor))
{
String text = (String) t.getTransferData(DataFlavor.stringFlavor);
return text;
}
}
catch (UnsupportedFlavorException e)
{
e.printStackTrace();
}
catch (IOException e)
{
e.printStackTrace();
}
return null;
}
public void setClipboard(String str)
{
StringSelection ss = new StringSelection(str);
Toolkit.getDefaultToolkit().getSystemClipboard().setContents(ss, this);
}
public void uso()
{
String claveVM = "Text I want insert";
setClipboard(claveVM + getClipboard());
}

You can't do it with plain text (string). You need RTF or HTML.