I am trying to store my object in MySQL database using java language. I am trying to convert object into byte so I can store it into LONGBLOB. But I am facing error i.e "NotSerializable Exception".
My Class whose object I want to sore:
public class Books implements Serializable {
private int isbn;
private String bookName;
private String author;
private String edition;
private int rowNo;
private int colNo;
private String shelfNo;
private String img;
private InputStream imag;
validation v = new Validation();
Database database;
public Books() { database = new Database(); }
.
.
setters & getters...
Method to call database method to insert object in database:
String className = this.getClass().getName();
database.insertBookRecord(this.getIsbn(), this, className);
this is the object of current class which I want to store.
following is the insertBookRecord method.
public void insertBookRecord(int isbn, Books book, String name) {
String query = "INSERT INTO Test VALUES (?, ?, ?)";
byte[] data = null;
//book = new Books();
try {
ByteArrayOutputStream baos = new ByteArrayOutputStream();
ObjectOutputStream oos = new ObjectOutputStream(baos);
oos.writeObject(book);
oos.flush();
oos.close();
baos.close();
data = baos.toByteArray();
}
catch(IOException ex) {
JOptionPane.showMessageDialog(null, ex.getMessage());
}
try {
//conn.setAutoCommit(false);
state = conn.prepareStatement(query);
state.setInt(1, isbn);
state.setString(2, name);
state.setObject(3, data);
state.executeUpdate();
//conn.commit();
}
catch(SQLException ex) {
JOptionPane.showMessageDialog(null, ex.getMessage());
}
finally {
close(3);
}
}
When I reach at statement oos.writeObject(book); Its stops with exception and displays the the package & Classname in the JOptionPane.
My book object has all the data fields I entered in the text fields. But I am unable to write it./convert it into Serializable format.
Any suggestions please?
Stack Trace:
java.io.NotSerializableException: com.my.classes.Database
at java.io.ObjectOutputStream.writeObject0(Unknown Source)
at java.io.ObjectOutputStream.defaultWriteFields(Unknown Source)
at java.io.ObjectOutputStream.writeSerialData(Unknown Source)
at java.io.ObjectOutputStream.writeOrdinaryObject(Unknown Source)
at java.io.ObjectOutputStream.writeObject0(Unknown Source)
at java.io.ObjectOutputStream.writeObject(Unknown Source)
at com.my.classes.Database.insertBookRecord(Database.java:123)
at com.my.classes.Books.insertBookRecord(Books.java:107)
at com.my.jlms.ManageBooks$2.actionPerformed(ManageBooks.java:308)
at javax.swing.AbstractButton.fireActionPerformed(Unknown Source)
at javax.swing.AbstractButton$Handler.actionPerformed(Unknown Source)
at javax.swing.DefaultButtonModel.fireActionPerformed(Unknown Source)
at javax.swing.DefaultButtonModel.setPressed(Unknown Source)
at javax.swing.plaf.basic.BasicButtonListener.mouseReleased(Unknown Source)
at java.awt.Component.processMouseEvent(Unknown Source)
at javax.swing.JComponent.processMouseEvent(Unknown Source)
at java.awt.Component.processEvent(Unknown Source)
at java.awt.Container.processEvent(Unknown Source)
at java.awt.Component.dispatchEventImpl(Unknown Source)
at java.awt.Container.dispatchEventImpl(Unknown Source)
at java.awt.Component.dispatchEvent(Unknown Source)
at java.awt.LightweightDispatcher.retargetMouseEvent(Unknown Source)
at java.awt.LightweightDispatcher.processMouseEvent(Unknown Source)
at java.awt.LightweightDispatcher.dispatchEvent(Unknown Source)
at java.awt.Container.dispatchEventImpl(Unknown Source)
at java.awt.Window.dispatchEventImpl(Unknown Source)
at java.awt.Component.dispatchEvent(Unknown Source)
at java.awt.EventQueue.dispatchEventImpl(Unknown Source)
at java.awt.EventQueue.access$500(Unknown Source)
at java.awt.EventQueue$3.run(Unknown Source)
at java.awt.EventQueue$3.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(Unknown Source)
at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(Unknown Source)
at java.awt.EventQueue$4.run(Unknown Source)
at java.awt.EventQueue$4.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(Unknown Source)
at java.awt.EventQueue.dispatchEvent(Unknown Source)
at java.awt.EventDispatchThread.pumpOneEventForFilters(Unknown Source)
at java.awt.EventDispatchThread.pumpEventsForFilter(Unknown Source)
at java.awt.EventDispatchThread.pumpEventsForHierarchy(Unknown Source)
at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
at java.awt.EventDispatchThread.run(Unknown Source)
You get the exception because you are trying to serialize an InputStream
private InputStream imag;
InputStream is not Serializable
You could omit this field when serializing by declaring it transient:
private transient InputStream imag;
Your imag is InputStream which is not implement Serializable. It should be a byte[] or String link to your imag location.
Edited: You should separate business from model object. Move insertBook method and database object from Book class to another class.
So the problem was InputStream as well as i was trying to Seralize the objects i.e V & database.
I just added transient e.g private transient Database database; and then declared database = new Database(); in the constructor. hence I was able to serialize it.
Thank you #Ralf, #Joseph, #Diyarbakir and #3kings for helping me out.
Related
I wrote a function that convert data to RDF and I need to upload this RDF to the fuseki server.
I tried to implement the code from here as follows
public class GenerateRDF {
public void setRDF(String[] personalData ) {
String serviceURI = "http://localhost:3030/Date";
DatasetAccessorFactory factory = null;
DatasetAccessor accessor;
accessor = factory.createHTTP(serviceURI);
String name = personalData[0];
String nationality = personalData[1];
String date = personalData[2];
String address = personalData[3];
String mobile = personalData[4];
String email = personalData[5];
String website = personalData[6];
String profesional = personalData[7];
String education = personalData[8];
String communication = personalData[9];
String digital = personalData[10];
String professional = personalData[11];
String management = personalData[12];
String certifications = personalData[13];
InputStream in = null;
Model model = ModelFactory.createDefaultModel();
Resource node = model.createResource(personURI)
.addProperty(FOAF.name, name)
.addProperty(FOAF.member, nationality)
.addProperty(FOAF.birthday, date)
.addProperty(FOAF.homepage, address)
.addProperty(FOAF.phone, mobile)
.addProperty(FOAF.yahooChatID, email)
.addProperty(FOAF.weblog, website)
.addProperty(FOAF.plan, profesional)
.addProperty(FOAF.knows, education)
.addProperty(FOAF.depiction, communication)
.addProperty(FOAF.interest, digital)
.addProperty(FOAF.publications, professional)
.addProperty(FOAF.maker, management)
.addProperty(FOAF.made, certifications);
String base = "http://test-projects.com/";
model.read(in, base, "RDF/XML");
accessor.putModel(model);
model.write(System.out);
}
}
Which returns the following Exception:
Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException
at java.io.FilterInputStream.read(Unknown Source)
at org.apache.xerces.impl.XMLEntityManager$RewindableInputStream.readAndBuffer(Unknown Source)
at org.apache.xerces.impl.XMLEntityManager.setupCurrentEntity(Unknown Source)
at org.apache.xerces.impl.XMLEntityManager.startEntity(Unknown Source)
at org.apache.xerces.impl.XMLEntityManager.startDocumentEntity(Unknown Source)
at org.apache.xerces.impl.XMLDocumentScannerImpl.setInputSource(Unknown Source)
at org.apache.xerces.parsers.DTDConfiguration.parse(Unknown Source)
at org.apache.xerces.parsers.DTDConfiguration.parse(Unknown Source)
at org.apache.xerces.parsers.XMLParser.parse(Unknown Source)
at org.apache.xerces.parsers.AbstractSAXParser.parse(Unknown Source)
at com.hp.hpl.jena.rdf.arp.impl.RDFXMLParser.parse(RDFXMLParser.java:151)
at com.hp.hpl.jena.rdf.arp.ARP.load(ARP.java:119)
at org.apache.jena.riot.lang.LangRDFXML.parse(LangRDFXML.java:142)
at org.apache.jena.riot.RDFParserRegistry$ReaderRIOTFactoryImpl$1.read(RDFParserRegistry.java:142)
at org.apache.jena.riot.RDFDataMgr.process(RDFDataMgr.java:760)
at org.apache.jena.riot.RDFDataMgr.read(RDFDataMgr.java:258)
at org.apache.jena.riot.RDFDataMgr.read(RDFDataMgr.java:244)
at org.apache.jena.riot.adapters.RDFReaderRIOT.read(RDFReaderRIOT.java:69)
at com.hp.hpl.jena.rdf.model.impl.ModelCom.read(ModelCom.java:274)
at GenerateRDF.setRDF(GenerateRDF.java:59)
at PersonalInfo$2.actionPerformed(PersonalInfo.java:251)
at javax.swing.AbstractButton.fireActionPerformed(Unknown Source)
at javax.swing.AbstractButton$Handler.actionPerformed(Unknown Source)
at javax.swing.DefaultButtonModel.fireActionPerformed(Unknown Source)
at javax.swing.DefaultButtonModel.setPressed(Unknown Source)
at javax.swing.plaf.basic.BasicButtonListener.mouseReleased(Unknown Source)
at java.awt.Component.processMouseEvent(Unknown Source)
at javax.swing.JComponent.processMouseEvent(Unknown Source)
at java.awt.Component.processEvent(Unknown Source)
at java.awt.Container.processEvent(Unknown Source)
at java.awt.Component.dispatchEventImpl(Unknown Source)
at java.awt.Container.dispatchEventImpl(Unknown Source)
at java.awt.Component.dispatchEvent(Unknown Source)
at java.awt.LightweightDispatcher.retargetMouseEvent(Unknown Source)
at java.awt.LightweightDispatcher.processMouseEvent(Unknown Source)
at java.awt.LightweightDispatcher.dispatchEvent(Unknown Source)
at java.awt.Container.dispatchEventImpl(Unknown Source)
at java.awt.Window.dispatchEventImpl(Unknown Source)
at java.awt.Component.dispatchEvent(Unknown Source)
at java.awt.EventQueue.dispatchEventImpl(Unknown Source)
at java.awt.EventQueue.access$500(Unknown Source)
at java.awt.EventQueue$3.run(Unknown Source)
at java.awt.EventQueue$3.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(Unknown Source)
at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(Unknown Source)
at java.awt.EventQueue$4.run(Unknown Source)
at java.awt.EventQueue$4.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(Unknown Source)
at java.awt.EventQueue.dispatchEvent(Unknown Source)
at java.awt.EventDispatchThread.pumpOneEventForFilters(Unknown Source)
at java.awt.EventDispatchThread.pumpEventsForFilter(Unknown Source)
at java.awt.EventDispatchThread.pumpEventsForHierarchy(Unknown Source)
at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
at java.awt.EventDispatchThread.run(Unknown Source)
Is there a way to fix this error? I'm open to solutions...
You might want to take a look here : https://hub.docker.com/r/stain/jena-fuseki/
There is a part on data loading that can guide you.
More specifically, load.sh and tdbloader that can be found here : https://github.com/stain/jena-docker/tree/master/jena-fuseki
I'm a bit puzzled by your question as you mention "upload a file to fuseki" in the tittle but your code does not refer to any file...
I want to get the actual created Primary Key.
I need it instantly for another Method but it returns an error.
But it returns a SQLE. Ive no idea wheres my Mistake.
I hope i gave you enaugh information.
(The System.out.println(id) is just for me to check if it returns the right PrimaryKey)
CreateTable:
CREATE TABLE "MitarbeiterInfo" ("Vorname" TEXT, "Nachname" TEXT, "Geburtsdatum" CHAR, "Wohnadresse" TEXT, "Postleitzahl" TEXT, "Eintrittsdatum" CHAR, "Handynummer" TEXT, "Email" TEXT, "ID" INTEGER PRIMARY KEY AUTOINCREMENT NOT NULL )
GuiClass:
public void actionPerformed(ActionEvent e) {
new Datenbank().mitarbeiterHinzufügen(
textField.getText(),textField_1.getText(),textField_2.getText(),textField_3.getText(),
textField_4.getText(),textField_5.getText(),textField_6.getText(),textField_7.getText());
refreshTable();
}
DatabaseClass:
public void mitarbeiterHinzufügen(String v, String n, String g, String w, String p, String e, String h, String email){
conn=Datenbank.dbConnector();
try {
String query="insert into MitarbeiterInfo (Vorname,Nachname,Geburtsdatum,Wohnadresse,Postleitzahl,Eintrittsdatum,Handynummer,Email,ID) values (?,?,?,?,?,?,?,?,?)";
PreparedStatement pst=conn.prepareStatement(query);
pst.setString(1, v);
pst.setString(2, n);
pst.setString(3, g);
pst.setString(4, w);
pst.setString(5, p);
pst.setString(6, e);
pst.setString(7, h);
pst.setString(8, email);
pst.execute();
String identitiy = "SELECT IDENTITY_VAL_LOCAL() FROM MitarbeiterInfo";
ResultSet rs = pst.executeQuery(identitiy);
rs.next();
int id = rs.getInt("1");
System.out.println(id);
JOptionPane.showMessageDialog(null, "Mitarbeiter hinzugefügt");
pst.close();
} catch (Exception b) {
b.printStackTrace();
}
}
That error ocurs:
java.sql.SQLException: not implemented by SQLite JDBC driver
at org.sqlite.Unused.unused(Unused.java:31)
at org.sqlite.PrepStmt.executeQuery(PrepStmt.java:596)
***at Datenbank.mitarbeiterHinzufügen(Datenbank.java:69)***
at GUI$3.actionPerformed(GUI.java:138)
at javax.swing.AbstractButton.fireActionPerformed(Unknown Source)
at javax.swing.AbstractButton$Handler.actionPerformed(Unknown Source)
at javax.swing.DefaultButtonModel.fireActionPerformed(Unknown Source)
at javax.swing.DefaultButtonModel.setPressed(Unknown Source)
at javax.swing.plaf.basic.BasicButtonListener.mouseReleased(Unknown Source)
at java.awt.Component.processMouseEvent(Unknown Source)
at javax.swing.JComponent.processMouseEvent(Unknown Source)
at java.awt.Component.processEvent(Unknown Source)
at java.awt.Container.processEvent(Unknown Source)
at java.awt.Component.dispatchEventImpl(Unknown Source)
at java.awt.Container.dispatchEventImpl(Unknown Source)
at java.awt.Component.dispatchEvent(Unknown Source)
at java.awt.LightweightDispatcher.retargetMouseEvent(Unknown Source)
at java.awt.LightweightDispatcher.processMouseEvent(Unknown Source)
at java.awt.LightweightDispatcher.dispatchEvent(Unknown Source)
at java.awt.Container.dispatchEventImpl(Unknown Source)
at java.awt.Window.dispatchEventImpl(Unknown Source)
at java.awt.Component.dispatchEvent(Unknown Source)
at java.awt.EventQueue.dispatchEventImpl(Unknown Source)
at java.awt.EventQueue.access$500(Unknown Source)
at java.awt.EventQueue$3.run(Unknown Source)
at java.awt.EventQueue$3.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.ProtectionDomain$1.doIntersectionPrivilege(Unknown Source)
at java.security.ProtectionDomain$1.doIntersectionPrivilege(Unknown Source)
at java.awt.EventQueue$4.run(Unknown Source)
at java.awt.EventQueue$4.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.ProtectionDomain$1.doIntersectionPrivilege(Unknown Source)
at java.awt.EventQueue.dispatchEvent(Unknown Source)
at java.awt.EventDispatchThread.pumpOneEventForFilters(Unknown Source)
at java.awt.EventDispatchThread.pumpEventsForFilter(Unknown Source)
at java.awt.EventDispatchThread.pumpEventsForHierarchy(Unknown Source)
at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
at java.awt.EventDispatchThread.run(Unknown Source)
In java.sql.ResultSet, below method's are defined for getInt:
getInt(int columnIndex)
getInt(String columnLabel)
I find problem with below line in your code:
int id = rs.getInt("1");
You should get value with one of the options:
int id = rs.getInt(1);
Or
int id = rs.getInt("Column_name");
Try
SELECT last_insert_rowid() FROM MitarbeiterInfo instead.
The exception you're getting seems to imply that IDENTITY_VAL_LOCAL() is not supported by SQLite.
I created a simple table in IBM DB2 named "NAMES" with a single column "FullName" with a datatype of VARCHAR(20). I've also created a GUI with a JTextfield and JButton to add data into the table through GUI. When the button is clicked, the text in the textfield will be inserted into the table NAMES. But there's an error when I click the button.
Here is the java code.
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import java.sql.*;
public class FirstClass extends JFrame implements ActionListener
{
private Connection connection;
private JTextField fieldTF;
private JButton addB;
public FirstClass() throws SQLException , ClassNotFoundException
{
setDefaultCloseOperation(this.EXIT_ON_CLOSE);
setLocationRelativeTo(null);
fieldTF = new JTextField(20);
addB = new JButton("Add");
Container cont = this.getContentPane();
cont.setLayout(new FlowLayout());
cont.add(fieldTF);
cont.add(addB);
setConnection();
addB.addActionListener(this);
pack();
validate();
setVisible(true);
}
public void setConnection() throws SQLException , ClassNotFoundException
{
Class.forName("com.ibm.db2.jcc.DB2Driver");
connection = DriverManager.getConnection("jdbc:db2://localhost:50000/COLINN","Colinn","ezioauditore");
System.out.print("Connected Succesfully");
}
public void write(String name) throws SQLException , ClassNotFoundException
{
PreparedStatement statement = null;
String query = null;
query = "INSERT INTO NAMES VALUES (?)";
statement.setString(1,name);
statement.executeUpdate();
}
public void actionPerformed(ActionEvent e)
{
try
{
write(fieldTF.getText());
}catch(Exception ex)
{
ex.printStackTrace();
}
}
public static void main(String args[]) throws SQLException , ClassNotFoundException
{
new FirstClass();
}
}
Here is the error:
java.lang.NullPointerException
at FirstYearProject.FirstClass.write(FirstClass.java:49)
at FirstYearProject.FirstClass.actionPerformed(FirstClass.java:58)
at javax.swing.AbstractButton.fireActionPerformed(Unknown Source)
at javax.swing.AbstractButton$Handler.actionPerformed(Unknown Source)
at javax.swing.DefaultButtonModel.fireActionPerformed(Unknown Source)
at javax.swing.DefaultButtonModel.setPressed(Unknown Source)
at javax.swing.plaf.basic.BasicButtonListener.mouseReleased(Unknown Source)
at java.awt.Component.processMouseEvent(Unknown Source)
at javax.swing.JComponent.processMouseEvent(Unknown Source)
at java.awt.Component.processEvent(Unknown Source)
at java.awt.Container.processEvent(Unknown Source)
at java.awt.Component.dispatchEventImpl(Unknown Source)
at java.awt.Container.dispatchEventImpl(Unknown Source)
at java.awt.Component.dispatchEvent(Unknown Source)
at java.awt.LightweightDispatcher.retargetMouseEvent(Unknown Source)
at java.awt.LightweightDispatcher.processMouseEvent(Unknown Source)
at java.awt.LightweightDispatcher.dispatchEvent(Unknown Source)
at java.awt.Container.dispatchEventImpl(Unknown Source)
at java.awt.Window.dispatchEventImpl(Unknown Source)
at java.awt.Component.dispatchEvent(Unknown Source)
at java.awt.EventQueue.dispatchEventImpl(Unknown Source)
at java.awt.EventQueue.access$400(Unknown Source)
at java.awt.EventQueue$3.run(Unknown Source)
at java.awt.EventQueue$3.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.ProtectionDomain$1.doIntersectionPrivilege(Unknown Source)
at java.security.ProtectionDomain$1.doIntersectionPrivilege(Unknown Source)
at java.awt.EventQueue$4.run(Unknown Source)
at java.awt.EventQueue$4.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.ProtectionDomain$1.doIntersectionPrivilege(Unknown Source)
at java.awt.EventQueue.dispatchEvent(Unknown Source)
at java.awt.EventDispatchThread.pumpOneEventForFilters(Unknown Source)
at java.awt.EventDispatchThread.pumpEventsForFilter(Unknown Source)
at java.awt.EventDispatchThread.pumpEventsForHierarchy(Unknown Source)
at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
at java.awt.EventDispatchThread.run(Unknown Source)
I've already imported External Jars from DB2 to establish connection with Java. I think there's a problem with the query or problem in executing it.
There's a problem here:
PreparedStatement statement = null; // **** set to null here
String query = null;
query = "INSERT INTO NAMES VALUES (?)";
statement.setString(1,name); // **** use it here!
Where does statement become non-null before you use it?
You need to key in on line 49 and 58 of the FirstClass.java class as per the exception stacktrace message, FirstClass.java:49.
Also, you will want to learn the general concepts of how to debug a NPE (NullPointerException). You should critically read your exception's stacktrace to find the line of code at fault, the line that throws the exception, and then inspect that line carefully, find out which variable is null, and then trace back into your code to see why. You will run into these again and again, trust me.
So here:
java.lang.NullPointerException
at FirstYearProject.FirstClass.write(FirstClass.java:49)
at FirstYearProject.FirstClass.actionPerformed(FirstClass.java:58)
The stacktrace tells you to carefully inspect lines 49 and 58.
Note, you need to create a PreparedStatement object before you try to use it. First you'd create a Connection, and then you'd use that Connection to create the PreparedStatement via Connection's preparedStatement(...) method. This is all well described in the Java JDBC Tutorials. Pay particular attention to the PreparedStatement subsection.
I have problems with idS. in sellContainer idS is 1 and in sellCtr is always 0 so the method addItemToSell is not working. Always give null pointer exception.
public class SellCtr{
private SellContainer sellContainer;
private OrderLineSell ols;
private int idS;
private int idOls;
public SellCtr(){
sellContainer = SellContainer.getInstance();
}
public void createSell(String date, Customer c, Employee e){
Sell sell = new Sell(date,c,e);
sellContainer.addSell(sell);
idS = sell.getId();
}
public void addItemToSell(OrderLineSell orderLineSell){
sellContainer.findSell(idS).addOrderLineSell(orderLineSell);
}
public int getId(){
return idS;
}
public int getIdOls(){
return idOls;
}
public Sell findSell(int idS){
return sellContainer.findSell(idS);
}
}
and the other class is :
public class SellContainer{
private ArrayList<Sell> sales;
private static int idS=0;
private static SellContainer instance=null;
public SellContainer(){
sales = new ArrayList<>();
}
public static SellContainer getInstance(){
if(instance == null){
instance = new SellContainer();
}
return instance;
}
public void addSell(Sell s){
idS++;
s.setId(idS);
sales.add(s);
}
public Sell findSell(int idS){
for(Sell sell : sales){
if(sell.getId()==idS){
return sell;
}
}
return null;
}
}
This is the error :
Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException
at controlLayer.SellCtr.addItemToSell(SellCtr.java:24)
at tuiLayer.SaleAddItemToSaleGUI$2.actionPerformed(SaleAddItemToSaleGUI.java:93)
at javax.swing.AbstractButton.fireActionPerformed(Unknown Source)
at javax.swing.AbstractButton$Handler.actionPerformed(Unknown Source)
at javax.swing.DefaultButtonModel.fireActionPerformed(Unknown Source)
at javax.swing.DefaultButtonModel.setPressed(Unknown Source)
at javax.swing.plaf.basic.BasicButtonListener.mouseReleased(Unknown Source)
at java.awt.Component.processMouseEvent(Unknown Source)
at javax.swing.JComponent.processMouseEvent(Unknown Source)
at java.awt.Component.processEvent(Unknown Source)
at java.awt.Container.processEvent(Unknown Source)
at java.awt.Component.dispatchEventImpl(Unknown Source)
at java.awt.Container.dispatchEventImpl(Unknown Source)
at java.awt.Component.dispatchEvent(Unknown Source)
at java.awt.LightweightDispatcher.retargetMouseEvent(Unknown Source)
at java.awt.LightweightDispatcher.processMouseEvent(Unknown Source)
at java.awt.LightweightDispatcher.dispatchEvent(Unknown Source)
at java.awt.Container.dispatchEventImpl(Unknown Source)
at java.awt.Window.dispatchEventImpl(Unknown Source)
at java.awt.Component.dispatchEvent(Unknown Source)
at java.awt.EventQueue.dispatchEventImpl(Unknown Source)
at java.awt.EventQueue.access$200(Unknown Source)
at java.awt.EventQueue$3.run(Unknown Source)
at java.awt.EventQueue$3.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.ProtectionDomain$1.doIntersectionPrivilege(Unknown Source)
at java.security.ProtectionDomain$1.doIntersectionPrivilege(Unknown Source)
at java.awt.EventQueue$4.run(Unknown Source)
at java.awt.EventQueue$4.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.ProtectionDomain$1.doIntersectionPrivilege(Unknown Source)
at java.awt.EventQueue.dispatchEvent(Unknown Source)
at java.awt.EventDispatchThread.pumpOneEventForFilters(Unknown Source)
at java.awt.EventDispatchThread.pumpEventsForFilter(Unknown Source)
at java.awt.EventDispatchThread.pumpEventsForHierarchy(Unknown Source)
at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
at java.awt.EventDispatchThread.run(Unknown Source)
I have rebuild the project and the exceptions changed.
EDIT 3 : I have made idS static and now it works. Thanks a lot guys!
I suggest you
make sure you are compiling all your classes. A build tool like maven or gradle will help.
you use enum for singletons. These are thread safe and simpler.
disable the feature in eclipse which allows you to run code which doesn't compile. This only delays finding errors which makes them worse.
I would replace
public class SellContainer{
private ArrayList<Sell> sales;
private static int idS=0;
private static SellContainer instance=null;
public SellContainer(){
sales = new ArrayList<>();
}
public static SellContainer getInstance(){
if(instance == null){
instance = new SellContainer();
}
return instance;
}
with
public enum SellContainer {
INSTANCE;
private final List<Sell> sales = new ArrayList<>();
private int idS = 0;
Initiate the object before the return object is back to the called method.
In SellContainer, if condition failure leads to give back the Sell Object as NULL.
You need to modify this logic.
return null;
I want to serialize and save an arraylist that contains a double [] arraylist in java. Here is my code.
FileOutputStream fileOutputStream = null;
ObjectOutputStream objectOutputStream = null;
FileInputStream fileInputStream = null;
ObjectInputStream objectInputStream = null;
public void writeArrayListToFile(ArrayList<ArrayList<double []>> arraylist, String outputFilePath){
System.out.println("Start saving the file at : " + outputFilePath);
try {
fileOutputStream = new FileOutputStream(outputFilePath , true);
objectOutputStream = new ObjectOutputStream(objectOutputStream);
objectOutputStream.writeObject(arraylist);
System.out.println("Arraylist Saved Successfully...");
} catch (FileNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
But I get an error and following is the stack trace.
Exception in thread "AWT-EventQueue-0" java.lang.NullPointerException
at java.io.ObjectOutputStream$BlockDataOutputStream.drain(Unknown Source)
at java.io.ObjectOutputStream$BlockDataOutputStream.setBlockDataMode(Unknown Source)
at java.io.ObjectOutputStream.(Unknown Source)
at com.fyp.imur2.SaveArrayListToFile.writeArrayListToFile(SaveArrayListToFile.java:24)
at com.fyp.imur2.JPanelJFreeChart.btnSaveGestureCollectionActionPerformed(JPanelJFreeChart.java:380)
at com.fyp.imur2.JPanelJFreeChart.access$5(JPanelJFreeChart.java:375)
at com.fyp.imur2.JPanelJFreeChart$6.actionPerformed(JPanelJFreeChart.java:166)
at javax.swing.AbstractButton.fireActionPerformed(Unknown Source)
at javax.swing.AbstractButton$Handler.actionPerformed(Unknown Source)
at javax.swing.DefaultButtonModel.fireActionPerformed(Unknown Source)
at javax.swing.DefaultButtonModel.setPressed(Unknown Source)
at javax.swing.plaf.basic.BasicButtonListener.mouseReleased(Unknown Source)
at java.awt.Component.processMouseEvent(Unknown Source)
at javax.swing.JComponent.processMouseEvent(Unknown Source)
at java.awt.Component.processEvent(Unknown Source)
at java.awt.Container.processEvent(Unknown Source)
at java.awt.Component.dispatchEventImpl(Unknown Source)
at java.awt.Container.dispatchEventImpl(Unknown Source)
at java.awt.Component.dispatchEvent(Unknown Source)
at java.awt.LightweightDispatcher.retargetMouseEvent(Unknown Source)
at java.awt.LightweightDispatcher.processMouseEvent(Unknown Source)
at java.awt.LightweightDispatcher.dispatchEvent(Unknown Source)
at java.awt.Container.dispatchEventImpl(Unknown Source)
at java.awt.Window.dispatchEventImpl(Unknown Source)
at java.awt.Component.dispatchEvent(Unknown Source)
at java.awt.EventQueue.dispatchEventImpl(Unknown Source)
at java.awt.EventQueue.access$200(Unknown Source)
at java.awt.EventQueue$3.run(Unknown Source)
at java.awt.EventQueue$3.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.ProtectionDomain$1.doIntersectionPrivilege(Unknown Source)
at java.security.ProtectionDomain$1.doIntersectionPrivilege(Unknown Source)
at java.awt.EventQueue$4.run(Unknown Source)
at java.awt.EventQueue$4.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.ProtectionDomain$1.doIntersectionPrivilege(Unknown Source)
at java.awt.EventQueue.dispatchEvent(Unknown Source)
at java.awt.EventDispatchThread.pumpOneEventForFilters(Unknown Source)
at java.awt.EventDispatchThread.pumpEventsForFilter(Unknown Source)
at java.awt.EventDispatchThread.pumpEventsForHierarchy(Unknown Source)
at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
at java.awt.EventDispatchThread.run(Unknown Source)
Can someone help me to solve this issue? Any help would be appreciated. Thanks in advance.
Need to pass fileOutputStream while constructing the instance of ObjectOutputStream
objectOutputStream = new ObjectOutputStream(fileOutputStream);
on the line
objectOutputStream = new ObjectOutputStream(objectOutputStream);
You try to call the constructor with the objectOutputStream object, which is null. Looks like you meant to call it with fileOutputStream, like this:
objectOutputStream = new ObjectOutputStream(fileOutputStream);