Difference between throw and throws keyword

any1 knows?????

Hi,
The throws keyword is used to declare that a method can throw a type of exception.
Ex:
public void foo() throws Exception {
The throw keyword actually throws an exception.
Ex:
throw new Exception("An error occured...");
/Roger

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  • Differences between awt and swing

    Ive written the following code, however Ive implemented the gui in awt rather then swing. Ive been told it hs too be in swing. What is the difference between swing and awt what will I need to change in my program so that its done using swing rather then the awt? Heres the code:
    // pp.java
    // Grant Brown
    // 22/02/02
    import java.awt.*;
    import java.awt.event.*;
    import java.io.*;
    import java.util.*;
    import javax.swing.*;
    // =========================================================
    // Class: pp
    // This class drives the customer manager. It contains the
    // main method which gets called as soon as this application
    // begins to run.
    // =========================================================
    class pp extends Frame implements ActionListener
    // Container of customer objects
    private Vector customers = new Vector (100);
    // List of names component. (Must specify java.awt in
    // front of List to distinguish the List class in the
    // java.awt package from the List class in the java.util
    // package.)
    private java.awt.List names = new java.awt.List ();
    // Delete and update button components.
    private Button delete;
    private Button update;
    // Default constructor.
    public pp ()
    // Assign "Paper Round Manager" to title bar of frame window.
    super ("Paper Round Manager");
    // Add a listener that responds to window closing
    // events. When this event occurs (by clicking on the
    // close box in the title bar), save customers and exit.
    addWindowListener (new WindowAdapter ()
    public void windowClosing
    (WindowEvent e)
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    System.exit (0);
    // Place an empty label in the north part of the frame
    // window. This is done to correct an AWT positioning
    // problem.
    Label l = new Label ();
    add ("North", l);
    // Place the names component in the center part of the
    // frame window.
    add ("Center", names);
    // Create a panel object to hold four buttons.
    Panel p = new Panel ();
    Button b;
    // Add an Insert button to the Panel object and register
    // the current pp object as a listener for button events.
    p.add (b = new Button ("Insert"));
    b.addActionListener (this);
    // Add a Delete button to the Panel object and register
    // the current pp object as a listener for button events.
    p.add (delete = new Button ("Delete"));
    delete.addActionListener (this);
    // The Delete button should be disabled until there is at
    // least one customer to delete.
    delete.setEnabled (false);
    // Add an Update button to the Panel object and register
    // the current pp object as a listener for button events.
    p.add (update = new Button ("Update"));
    update.addActionListener (this);
    // The Update button should be disabled until there is at
    // least one customer to update.
    update.setEnabled (false);
    // Add a Finish button to the Panel object and register
    // the current customer object as a listener for button events.
    p.add (b = new Button ("Finish"));
    b.addActionListener (this);
    // Add the panel object to the frame window container.
    add ("South", p);
    // Set the background of the frame window container to
    // lightGray
    setBackground (Color.lightGray);
    // Set the size of the frame window container to 400
    // pixels horizontally by 200 pixels vertically.
    setSize (400, 200);
    // Allow the user to resize the frame window.
    setResizable (true);
    // Load all contacts.
    loadCustomers ();
    // Make sure that the frame window is visible.
    setVisible (true);
    public void actionPerformed (ActionEvent e)
    if (e.getActionCommand ().equals ("Delete"))
    delete ();
    else
    if (e.getActionCommand ().equals ("Finish"))
    saveCustomers ();
    System.exit (0);
    else
    if (e.getActionCommand ().equals ("Insert"))
    insert ();
    else
    update ();
    public Insets getInsets ()
    // Return an Insets object that describes the number of
    // pixels to reserve as a border around the edges of the
    // frame window.
    return new Insets (10, 10, 10, 10);
    public static void main (String [] args)
    // Create a new pp object and let it do its thing.
    new pp ();
    private void delete ()
    // Obtain index of selected contact item from the names
    // component.
    int index = names.getSelectedIndex ();
    // If no item was selected, index is -1. We cannot update
    // a contact if no contact item in the names component was
    // selected - because we would have nothing to work with.
    if (index != -1)
    // Remove the contact item from the names component.
    names.remove (index);
    // Remove the Customer object from the contacts Vector
    // object.
    customers.remove (index);
    // If there are no more customers ...
    if (customers.size () == 0)
    delete.setEnabled (false);
    update.setEnabled (false);
    else
    // Make sure that the first contact item in the names
    // list is highlighted.
    names.select (0);
    private void insert ()
    // Create an Insert data entry form to enter information
    // for a new customer.
    DataEntryForm def = new DataEntryForm (this, "Insert");
    // If the bOk Boolean flag is set, this indicates the user
    // exited the form by pressing the Ok button.
    if (def.bOk)
    // Create a Contact object and assign information from
    // the form to its fields.
    Customer temp = new Customer ();
    temp.name = new String (def.name.getText ());
    temp.publication = new String (def.publication.getText ());
    temp.round = new String (def.round.getText ());
    temp.address = new String (def.address.getText ());
    temp.phone = new String (def.phone.getText ());
    // Add a new customer item to the names component.
    names.add (temp.name + ", " + temp.publication);
    // Add the Customer object to the contacts Vector
    // object.
    customers.add (temp);
    // Make sure that the Delete and Update buttons are
    // enabled.
    delete.setEnabled (true);
    update.setEnabled (true);
    // Destroy the dialouge box.
    def.dispose ();
    // Make sure that the first customer item in the names list
    // is highlighted.
    names.select (0);
    // ===========================================================
    // Load all contacts from contacts.dat into the contacts
    // Vector object. Also, make sure that the last name/first
    // name from each contact is combined into a String object and
    // inserted into the names component - as a contact item.
    // ===========================================================
    private void loadCustomers ()
    FileInputStream fis = null;
    try
    fis = new FileInputStream ("Customers.dat");
    DataInputStream dis = new DataInputStream (fis);
    int nCustomers = dis.readInt ();
    for (int i = 0; i < nCustomers; i++)
    Customer temp = new Customer ();
    temp.name = dis.readUTF ();
    temp.publication = dis.readUTF ();
    temp.round = dis.readUTF ();
    temp.address = dis.readUTF ();
    temp.phone = dis.readUTF ();
    names.add (temp.name + ", " + temp.publication);
    customers.add (temp);
    if (nCustomers > 0)
    delete.setEnabled (true);
    update.setEnabled (true);
    catch (IOException e)
    finally
    if (fis != null)
    try
    fis.close ();
    catch (IOException e) {}
    // Make sure that the first contact item in the names list
    // is highlighted.
    names.select (0);
    // ========================================================
    // Save all Customer objects from the customer Vector object
    // to customer.dat. The number of customerss are saved as an
    // int to make it easy for loadCustomers () to do its job.
    // ========================================================
    private void saveCustomers ()
    FileOutputStream fos = null;
    try
    fos = new FileOutputStream ("customers.dat");
    DataOutputStream dos = new DataOutputStream (fos);
    dos.writeInt (customers.size ());
    for (int i = 0; i < customers.size (); i++)
    Customer temp = (Customer) customers.elementAt (i);
    dos.writeUTF (temp.name);
    dos.writeUTF (temp.publication);
    dos.writeUTF (temp.round);
    dos.writeUTF (temp.address);
    dos.writeUTF (temp.phone);
    catch (IOException e)
    MsgBox mb = new MsgBox (this, "PP Error",
    e.toString ());
    mb.dispose ();
    finally
    if (fos != null)
    try
    fos.close ();
    catch (IOException e) {}
    private void update ()
    // Obtain index of selected customer item from the names
    // component.
    int index = names.getSelectedIndex ();
    // If no item was selected, index is -1. We cannot update
    // a customer if no customer item in the names component was
    // selected - because we would have nothing to work with.
    if (index != -1)
    // Obtain a reference to the customer object (from the
    // customers Vector object) that is associated with the
    // index.
    Customer temp = (Customer) customers.elementAt (index);
    // Create and display an update entry form.
    DataEntryForm def = new DataEntryForm (this, "Update",
    temp.name,
    temp.publication,
    temp.round,
    temp.address,
    temp.phone);
    // If the user pressed Ok...
    if (def.bOk)
    // Update the customer information in the customers
    // Vector object.
    temp.name = new String (def.name.getText ());
    temp.publication = new String (def.publication.getText ());
    temp.round = new String (def.round.getText ());
    temp.address = new String (def.address.getText ());
    temp.phone = new String (def.phone.getText ());
    // Make sure the screen reflects the update.
    names.replaceItem (temp.name + ", " + temp.publication,
    index);
    // Destroy the dialouge box.
    def.dispose ();
    // Make sure that the first customer item in the names
    // list is highlighted.
    names.select (0);

    Ive doen pretty much what you said burt now my program isnt working at all. The window comes up but instead of doing something when you click the button it just throws shit loads of exceptions. Heres my abridged code
    // pp.java
    // Grant Brown
    // 22/02/02
    import java.awt.*;
    import java.awt.event.*;
    import java.io.*;
    import java.util.*;
    import javax.swing.*;
    // =========================================================
    // Class:PP
    // This class drives the Paper Round manager. It contains the
    // main method which gets called as soon as this application
    // begins to run.
    // =========================================================
    class pp extends JFrame implements ActionListener
    // Container of customer objects (one object per customer)
    private Vector customers = new Vector (100);
    // List of names component. (Must specify java.awt in
    // front of List to distinguish the List class in the
    // java.awt package from the List class in the java.util
    // package.)
    private java.awt.List names = new java.awt.List ();
    // Delete and update button components.
    private JButton delete;
    private JButton update;
    // Default constructor.
    public pp ()
    // Assign Contact Manager to title bar of frame window.
    super ("Paper Round Manager");
    // Add a listener that responds to window closing
    // events. When this event occurs (by clicking on the
    // close box in the title bar), save contacts and exit.
    addWindowListener (new WindowAdapter ()
    public void windowClosing
    (WindowEvent e)
    saveCustomers ();
    System.exit (0);
    // Place an empty label in the north part of the frame
    // window. This is done to correct an AWT positioning
    // problem. (One thing that you'll come to realize as
    // you work with the AWT is that there are lots of bugs.)
    JLabel l = new JLabel ();
    getContentPane().add ("North", l);
    // Place the names component in the center part of the
    // frame window.
    getContentPane().add ("Center", names);
    // Create a panel object to hold four buttons.
    JPanel p = new JPanel ();
    JButton b;
    // Add an Insert button to the Panel object and register
    // the current cm object as a listener for button events.
    p.add (b = new JButton ("Insert"));
    b.addActionListener (this);
    // Add a Delete button to the Panel object and register
    // the current cm object as a listener for button events.
    p.add (delete = new JButton ("Delete"));
    delete.addActionListener (this);
    // The Delete button should be disabled until there is at
    // least one contact to delete.
    delete.setEnabled (false);
    // Add an Update button to the Panel object and register
    // the current cm object as a listener for button events.
    p.add (update = new JButton ("Update"));
    update.addActionListener (this);
    // The Update button should be disabled until there is at
    // least one contact to update.
    update.setEnabled (false);
    // Add a Finish button to the Panel object and register
    // the current cm object as a listener for button events.
    p.add (b = new JButton ("Finish"));
    b.addActionListener (this);
    // Add the panel object to the frame window container.
    getContentPane().add ("South", p);
    // Set the background of the frame window container to
    // lightGray (to give a pleasing effect).
    setBackground (Color.lightGray);
    // Set the size of the frame window container to 400
    // pixels horizontally by 200 pixels vertically.
    setBounds (50, 100, 400, 200);
    // Do not allow the user to resize the frame window.
    loadCustomers ();
    // Load all contacts.
    setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    // Make sure that the frame window is visible.
    setVisible (true);
    public void actionPerformed (ActionEvent e)
    if (e.getActionCommand ().equals ("Delete"))
    delete ();
    else
    if (e.getActionCommand ().equals ("Finish"))
    saveCustomers ();
    System.exit (0);
    else
    if (e.getActionCommand ().equals ("Insert"))
    insert ();
    else
    update ();
    public Insets getInsets ()
    // Return an Insets object that describes the number of
    // pixels to reserve as a border around the edges of the
    // frame window.
    return new Insets (10, 10, 10, 10);
    public static void main (String [] args)
    // Create a new cm object and let it do its thing.
    new pp ();
    private void delete ()
    // Obtain index of selected customer item from the names
    // component.
    int index = names.getSelectedIndex ();
    // If no item was selected, index is -1. We cannot update
    // a contact if no contact item in the names component was
    // selected - because we would have nothing to work with.
    if (index != -1)
    // Remove the customer item from the names component.
    names.remove (index);
    // Remove the Customer object from the contacts Vector
    // object.
    customers.remove (index);
    // If there are no more customers ...
    if (customers.size () == 0)
    delete.setEnabled (false);
    update.setEnabled (false);
    else
    // Make sure that the first contact item in the names
    // list is highlighted.
    names.select (0);
    private void insert ()
    // Create an Insert data entry form to enter information
    // for a new contact.
    DataEntryForm def = new DataEntryForm (this, "Insert");
    // If the bOk Boolean flag is set, this indicates the user
    // exited the form by pressing the Ok button.
    if (def.bOk)
    // Create a Customer object and assign information from
    // the form to its fields.
    Customer temp = new Customer ();
    temp.name = new String (def.name.getText ());
    temp.publication = new String (def.publication.getText ());
    temp.address = new String (def.address.getText ());
    temp.round = new String (def.round.getText ());
    temp.phone = new String
              (def.phone.getText ());
    // Add a new customer item to the names component.
    names.add (temp.publication + ", " + temp.address);
    // Add the Customer object to the contacts Vector
    // object.
    customers.add (temp);
    // Make sure that the Delete and Update buttons are
    // enabled.
    delete.setEnabled (true);
    update.setEnabled (true);
    // Destroy the dialog box.
    def.dispose ();
    // Make sure that the first customer item in the names list
    // is highlighted.
    names.select (0);
    // ===========================================================
    // Load all customers from customers.dat into the customers
    // Vector object. Also, make sure that the last name/first
    // name from each contact is combined into a String object and
    // inserted into the names component - as a contact item.
    // ===========================================================
    private void loadCustomers ()
    FileInputStream fis = null;
    try
    fis = new FileInputStream ("customers.dat");
    DataInputStream dis = new DataInputStream (fis);
    int nCustomers = dis.readInt ();
    for (int i = 0; i < nCustomers; i++)
    Customer temp = new Customer ();
    temp.name = dis.readUTF ();
    temp.publication = dis.readUTF ();
    temp.address = dis.readUTF ();
    temp.round = dis.readUTF ();
    temp.phone = dis.readUTF ();
    names.add (temp.publication + ", " + temp.address);
    customers.add (temp);
    if (nCustomers > 0)
    delete.setEnabled (true);
    update.setEnabled (true);
    catch (IOException e)
    finally
    if (fis != null)
    try
    fis.close ();
    catch (IOException e) {}
    // Make sure that the first customer item in the names list
    // is highlighted.
    names.select (0);
    // ========================================================
    // Save all customer objects from the contacts Vector object
    // to customers.dat. The number of contacts are saved as an
    // int to make it easy for loadCustomers () to do its job.
    // ========================================================
    private void saveCustomers ()
    FileOutputStream fos = null;
    try
    fos = new FileOutputStream ("customers.dat");
    DataOutputStream dos = new DataOutputStream (fos);
    dos.writeInt (customers.size ());
    for (int i = 0; i < customers.size (); i++)
    Customer temp = (Customer) customers.elementAt (i);
    dos.writeUTF (temp.name);
    dos.writeUTF (temp.publication);
    dos.writeUTF (temp.address);
    dos.writeUTF (temp.round);
    dos.writeUTF (temp.phone);
    catch (IOException e)
    MsgBox mb = new MsgBox (this, "PP Error",
    e.toString ());
    mb.dispose ();
    finally
    if (fos != null)
    try
    fos.close ();
    catch (IOException e) {}
    private void update ()
    // Obtain index of selected customer item from the names
    // component.
    int index = names.getSelectedIndex ();
    // If no item was selected, index is -1. We cannot update
    // a customer if no customer item in the names component was
    // selected - because we would have nothing to work with.
    if (index != -1)
    // Obtain a reference to the Customer object (from the
    // customer Vector object) that is associated with the
    // index.
    Customer temp = (Customer) customers.elementAt (index);
    // Create and display an update entry form.
    DataEntryForm def = new DataEntryForm (this, "Update",
    temp.name,
    temp.publication,
    temp.address,
    temp.round,
    temp.phone);
    // If the user pressed Ok...
    if (def.bOk)
    // Update the customer information in the customers
    // Vector object.
    temp.name = new String (def.name.getText ());
    temp.publication = new String (def.publication.getText ());
    temp.address = new String (def.address.getText ());
    temp.round = new String (def.round.getText ());
    temp.phone = new String (def.phone.getText ());
    // Make sure the screen reflects the update.
    names.replaceItem (temp.publication + ", " + temp.address,
    index);
    // Destroy the dialog box.
    def.dispose ();
    // Make sure that the first customer item in the names
    // list is highlighted.
    names.select (0);
    // ========================================================
    // Class: Customer
    // This class describes the contents of a business customer.
    // ========================================================
    class Customer
    public String name;
    public String publication;
    public String address;
    public String round;
    public String phone;
    // ==========================================================
    // Class: DataEntryForm
    // This class provides a data entry form for entering customer
    // information.
    // ==========================================================
    class DataEntryForm extends JDialog implements ActionListener
    // bOk is a boolean flag. When true, it indicates that
    // the Ok button was pressed to terminate the dialog box
    // (as opposed to the Cancel button).
    public boolean bOk;
    // The following components hold the text that the user
    // entered into the visible text fields.
    public JTextField name;
    public JTextField publication;
    public JTextField address;
    public JTextField round;
    public JTextField phone;
    public void actionPerformed (ActionEvent e)
    // If the user pressed the Ok button, indicate this
    // by assigning true to bOk.
    if (e.getActionCommand ().equals ("Ok"))
    bOk = true;
    // Destroy the dialog box and return to the point
    // just after the creation of the DataEntryForm object.
    dispose ();
    public DataEntryForm (JFrame parent, String title)
    // Call the other constructor. The current constructor
    // is used for insert operations. The other constructor
    // is used for update operations.
    this (parent, title, "", "", "", "", "");
    public DataEntryForm (JFrame parent, String title,
    String name, String publication,
    String address, String round,
    String phone)
    // Initialize the superclass layer.
    super (parent, title, true);
    // Choose a grid bag layout so that components can be more
    // accurately positioned. (It looks nicer.)
    setLayout (new GridBagLayout ());
    // Add appropriate first name, last name, phone, fax, and
    // email components to the current DataEntryForm container.
    // (Remember, DataEntryForm is a subclass of Dialog.
    // Dialog is a container. Therefore, DataEntryForm
    // inherits the ability to be a container.)
    addComponent (this, new JLabel ("Name: "), 0, 0, 1, 1,
    GridBagConstraints.NONE,
    GridBagConstraints.WEST);
    this.name = new JTextField (15);
    addComponent (this, this.name, 1, 0, 1, 1,
    GridBagConstraints.NONE,
    GridBagConstraints.CENTER);
    if (title.equals ("Update"))
    this.name.setText (name);
    addComponent (this, new JLabel ("Publications: "), 0, 1, 1, 1,
    GridBagConstraints.NONE,
    GridBagConstraints.WEST);
    this.publication = new JTextField (15);
    addComponent (this, this.publication, 1, 1, 1, 1,
    GridBagConstraints.NONE,
    GridBagConstraints.CENTER);
    if (title.equals ("Update"))
    this.publication.setText (publication);
    addComponent (this, new JLabel ("Address "), 0, 2, 1, 1,
    GridBagConstraints.NONE,
    GridBagConstraints.WEST);
    this.address = new JTextField (15);
    addComponent (this, this.address, 1, 2, 1, 1,
    GridBagConstraints.NONE,
    GridBagConstraints.CENTER);
    if (title.equals ("Update"))
    this.address.setText (address);
    addComponent (this, new JLabel ("Round No "), 0, 3, 1, 1,
    GridBagConstraints.NONE,
    GridBagConstraints.WEST);
    this.round = new JTextField (15);
    addComponent (this, this.round, 1, 3, 1, 1,
    GridBagConstraints.NONE,
    GridBagConstraints.CENTER);
    if (title.equals ("Update"))
    this.round.setText (round);
    addComponent (this, new JLabel ("Phone Number "), 0, 4, 1, 1,
    GridBagConstraints.NONE,
    GridBagConstraints.WEST);
    this.phone = new JTextField (15);
    addComponent (this, this.phone, 1, 4, 1, 1,
    GridBagConstraints.NONE,
    GridBagConstraints.CENTER);
    if (title.equals ("Update"))
    this.phone.setText (phone);
    addComponent (this, new JLabel (""), 0, 5, 1, 1,
    GridBagConstraints.NONE,
    GridBagConstraints.CENTER);
    addComponent (this, new JLabel (""), 1, 5, 1, 1,
    GridBagConstraints.NONE,
    GridBagConstraints.CENTER);
    JButton b;
    // Add an Ok button to this container.
    addComponent (this, b = new JButton ("Ok"), 0, 6, 1, 1,
    GridBagConstraints.NONE,
    GridBagConstraints.CENTER);
    b.addActionListener (this);
    // Add a Cancel button to this container.
    addComponent (this, b = new JButton ("Cancel"), 1, 6, 1, 1,
    GridBagConstraints.NONE,
    GridBagConstraints.CENTER);
    b.addActionListener (this);
    // Set the size of the dialog window to 250 pixels
    // horizontally by 200 pixels vertically.
    setSize (250, 200);
    // Do not allow users to resize the dialog window.
    setResizable (false);
    // Make sure that the dialog window is visible.
    setVisible (true);
    private void addComponent (Container con, Component com,
    int gridx, int gridy,
    int gridw, int gridh, int fill,
    int anchor)
    // Get the current layout manager. It is assumed to
    // be a GridBagLayout object.
    LayoutManager lm = con.getLayout ();
    // Create a GridBagConstraints object to make it
    // possible to customize component positioning.
    GridBagConstraints gbc = new GridBagConstraints ();
    // Assign the x and y grid positions.
    gbc.gridx = gridx;
    gbc.gridy = gridy;
    // Assign the number of grid blocks horizontally and
    // vertically that are occupied by the component.
    gbc.gridwidth = gridw;
    gbc.gridheight = gridh;
    // Specify the component's resize policy (fill) and
    // the direction in which the component is positioned
    // when its size is smaller than available space (anchor).
    gbc.fill = fill;
    gbc.anchor = anchor;
    // Set the new constraints that the grid bag layout
    // manager will use.
    ((GridBagLayout) lm).setConstraints (com, gbc);
    // Add the component to the container.
    con.add (com);
    // ===========================================================
    // Class: MsgBox
    // This class displays a message box to the user. The message
    // is usually an error message. The user must press the Ok
    // button to terminate the message box.
    // ===========================================================
    class MsgBox extends JDialog implements ActionListener
    public void actionPerformed (ActionEvent e)
    // Terminate the dialog box in response to the user
    // pressing the Ok button.
    dispose ();
    public MsgBox (JFrame parent, String title, String msg)
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    super (parent, title, true);
    // Store the msg argument in a Label object and add
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    JLabel l = new JLabel (msg);
    add ("Center", l);
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    JButton b = new JButton ("Ok");
    add ("South", b);
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  • Difference Between BADI and User Exits

    Hi..
    generally BADIs & User Exis are used exensively in SAP SD...
    Can anybody throw some light waht is difference between them ...
    Kindly please reply......
    Regards
    Nisha

    Hi
    ifference Between BADI and User Exits
    Business Add-Ins are a new SAP enhancement technique based on ABAP Objects. They can be inserted into the SAP System to accommodate user requirements too specific to be included in the standard delivery. Since specific industries often require special functions, SAP allows you to predefine these points in your software.
    As with customer exits two different views are available:
    In the definition view, an application programmer predefines exit points in a source that allow specific industry sectors, partners, and customers to attach additional software to standard SAP source code without having to modify the original object.
    In the implementation view, the users of Business Add-Ins can customize the logic they need or use a standard logic if one is available.
    In contrast to customer exits, Business Add-Ins no longer assume a two-level infrastructure (SAP and customer solutions), but instead allow for a multi-level system landscape (SAP, partner, and customer solutions, as well as country versions, industry solutions, and the like). Definitions and implementations of Business Add-Ins can be created at each level within such a system infrastructure.
    SAP guarantees the upward compatibility of all Business Add-In interfaces. Release upgrades do not affect enhancement calls from within the standard software nor do they affect the validity of call interfaces. You do not have to register Business Add-Ins in SSCR.
    The Business Add-In enhancement technique differentiates between enhancements that can only be implemented once and enhancements that can be used actively by any number of customers at the same time. In addition, Business Add-Ins can be defined according to filter values. This allows you to control add-in implementation and make it dependent on specific criteria (on a specific Country value, for example).
    All ABAP sources, screens, GUIs, and table interfaces created using this enhancement technique are defined in a manner that allows customers to include their own enhancements in the standard. A single Business Add-In contains all of the interfaces necessary to implement a specific task.
    The actual program code is enhanced using ABAP Objects. In order to better understand the programming techniques behind the Business Add-In enhancement concept, SAP recommends reading the section on ABAP Objects.
    What is difference between badi and user-exists?
    What is difference between enhancements and user-exists? and what is the full form of BADI?
    I have another doubt in BDC IN BDC WE HAVE MSEGCALL (i did not remember the > correct name) where the error logs are stored, MSEGCALL is a table or structure.
    What is the system landscape?
    1) Difference between BADI and USER-EXIT.
        i) BADI's can be used any number of times, where as USER-EXITS can be used only one time.
           Ex:- if your assigning a USER-EXIT to a project in (CMOD), then you can not assign the same to other project.
        ii) BADI's are oops based.
    2) About 'BDCMSGCOLL' it is a structure.  Used for finding error records.
    3) Full form of BADI 'Business addins'.
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  • Difference between b2bmessageid and PROTOCOLMESSAGEID

    Hi,
    Can somebody explain the difference between b2bmessageid and PROTOCOLMESSAGEID?
    When trying to resumit failed outbound message(using resubmission java comand), can I resubmit it based on the protocol message id?
    Thanks,
    Kevin

    Thanks, Kalyan, Ramesh
    We're using the Rosettanet and find that B2BmessageID always has the same values as PROTOCOLMESSAGEID.
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    When resubmission failed, we got the detail error info below. Actually AAA is Seller and BBB is a buyer. Can you please throw some light on it, thanks?
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    Also verify agreement effectiveToDate
    StackTrace:
    Error -: AIP-50501: Trading partner agreement not found for the given input values: From party
    [NAME-ROLE] "AAA-Buyer", To party [NAME-ROLE] "BBB-Seller", Collaboration
    name "3A4"; also verify agreement effectiveToDate
    at oracle.tip.adapter.b2b.tpa.RepoDataAccessor.getAgreementName(RepoDataAccessor.ja
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    at oracle.tip.adapter.b2b.tpa.TPAIdentifier.identifyTPA(TPAIdentifier.java:177)
    at oracle.tip.adapter.b2b.tpa.TPAProcessor.processTPA(TPAProcessor.java:496)
    at oracle.tip.adapter.b2b.tpa.TPAProcessor.processOutgoingTPA(TPAProcessor.java:208
    at oracle.tip.adapter.b2b.engine.Engine.processOutgoingMessage(Engine.java:984)
    at oracle.tip.adapter.b2b.data.MsgListener.onMessage(MsgListener.java:740)
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    at java.lang.Thread.run(Thread.java:534)
    Thanks,
    Kevin Lei

  • 294.What is the difference between TCP and UDP

    What is the difference between TCP and UDP

    The difference between TCP and UDP is that UDP throws datagram packets over the wire not concerned whether it arrives at its destination or not. TCP attempts to facilitate the notion of a connection by requiring an acknowledgement by the recipient and continually resending the packets until it receives the acknowledgement or gets a timeout. In a way TCP can be thought of as a layer over UDP but it's more than that. A good analogy is the beginning of the school day vs the end of the school day. In the beginning children enter school in a line and in an orderly fashion. Each child is accounted for. Each child has a defined classroom destination. Likewise TCP packets are sequenced, accounted for, and have a certain destination. At the end of the day all the kids pour out of the building randomly with no regard of whether their buddies are on detention or not. Any particular kid could be heading straight home or to the mall and no accounting is taken. In the same way UPD packets are dispersed from the sender without regard for order. Any packet to make a pit stop at a particular router on the network and no accounting is done to ensure it makes it all the way to the recipient.

  • What is the difference between Structure and Work area

    Hi Guys,
    What is the difference between Structure and work area?
    Are they same with different names?
    Thanks,
    mini.

    hey buddies,*
    i had this same doubt for a long time and i have my finds with me ie wa and structure are the same but wa can hold a single record but structure cannot hold data in it but according to the previous posts  folks  say structure too holds data as wa does but i guess when debugging wa holds data and structure doesnt hold bcoz i tried.
    types : begin of str_mara,
                 matnr type mara-matnr,
                ernam type mara-ernam,
                end of str_mara.
    data it_mara type table of str_mara.
    select matnr ernam from mara into it_mara where matnr = '100-101'.
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    loop at it_mara into str_mara.
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    endloop.
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    Edited by: arun_aime on Feb 12, 2010 4:41 PM

  • Wanna difference between Tomact4x and Tomcat5x

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    1
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  • Media Foundation Source or H264 / AC3 differences between Windows and Phone 8?

    I've got a working Matroska (MKV) Media Foundation Source for a Windows Store app (PC x86). It will play several different matroska files that contain H264 encoded video and AC3-encoded audio.  It even has seek support.  I've written the app
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    6-channel, so that made me wonder if it was failing because WP8 supports 2-channel max, but I would have thought the audio just wouldn't work and the video would play normally.
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    *edit* - just to be more specific, I can parse the file and create the presentation descriptor without errors.  But when I finish opening the file and call the event for that, nothing else happens.  What is weird is that the javascript video player
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    Lee McPherson

    Thanks, not a bad suggestion to try. 
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    and AC3 audio), I only get the type and subtype properties. Everything else is zero or null.  This is because in my MFSource, I only set the type and subtype.  This still allows the video to play on my windows machine.  I assume the
    built-in MFTransform for H264 video-to-uncompressed video parses the stream to get the relevant information.  Likewise for audio.
    On Windows Phone, when querying the file's MediaEncodingProfile, I get the same result. This is telling me that my MFSource will parse the file properly and set the subtypes for video and audio correctly.  Everything else is still null or zero. 
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    Perhaps, I need to fill in the video and audio stream properties on the Windows Phone version.  I really don't want to because that would mean having to parse some of the underlying video and audio streams themselves, not just parsing the container
    information.  (More work!)  But this is what I mean when I ask about the differences between Windows and Windows Phone... perhaps the WP8.1 & Windows MFTransforms are different? 
    *EDIT* - I do get a JavaScript Console error that I didn't notice before: AUDIO/VIDEO: unknown MIME type.  (VS error code: MEDIA12899)
    Lee McPherson

  • Difference between poh and pov in module pool programming

    hi all,
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    Hi,
    POV gives you F4 help.
    like:
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    PROCESS ON VALUE-REQUEST.
      FIELD f MODULE mod.
    After the PROCESS ON VALUE-REQUEST statement, you can only use the MODULE statement together with the FIELD statement. When the user chooses F4 for a field f, the system calls the module mod belonging to the FIELD statement. If there is more than one FIELD statement for the same field f, only the first is executed. The module mod is defined in the ABAP program like a normal PAI module. However, the contents of the screen field f are not available, since it is not transported by the FIELD statement during the PROCESS ON HELP-REQUEST event. You can now program your own value lists in the module. However, this procedure is only recommended if it really is not possible to use a search help. Defining search helps is much easier than PROCESS ON VALUE-REQUEST, since the system takes over some of the standard operations, such as getting field contents from the screen. It also ensures that the F4 help has a uniform look and feel throughout the system. Furthermore, it means that you do not have to reassign input help to fields on each screen.
    Despite the introduction of search helps (and search help exits), there are still cases in which you need to use parts of the standard F4 functions directly. In this case, there are some standard function modules that you can use in the POV event. They support search helps, as well as all other kinds of input help, and are responsible for data transport between the screen and the input help. These alll  have the prefix F4IF_. The most important are:
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    Calls the input help of the ABAP Dictionary dynamically. You can pass the component names of a structure or database table of the ABAP Dictionary to the function module in the import parameters TABNAME and FIELDNAME. The function module starts the ABAP Dictionary input help for this component. All of the relevant screen fields are read. If you specify the import parameters DYNPPROG, DYNPNR, and DYNPROFIELD, the user’s selection is returned to the corresponding field on the screen. If you specify the table parameter RETURN_TAB, the selection is returned into the table instead.
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    There are also two function modules - DYNP_VALUES_READ and DYNP_VALUES_UPDATE - that can read the values of screen fields and return values to them during the POV event. For further information, refer to the relevant function module documentation.
    Input help in dialog modules
    REPORT demo_dynpro_f4_help_module.
    TYPES: BEGIN OF values,
             carrid TYPE spfli-carrid,
             connid TYPE spfli-connid,
           END OF values.
    DATA: carrier(3) TYPE c,
          connection(4) TYPE c.
    DATA: progname TYPE sy-repid,
          dynnum   TYPE sy-dynnr,
          dynpro_values TYPE TABLE OF dynpread,
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    CALL SCREEN 100.
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      progname = sy-repid.
      dynnum   = sy-dynnr.
      CLEAR: field_value, dynpro_values.
      field_value-fieldname = 'CARRIER'.
      APPEND field_value TO dynpro_values.
    ENDMODULE.
    MODULE cancel INPUT.
      LEAVE PROGRAM.
    ENDMODULE.
    MODULE value_carrier INPUT.
      CALL FUNCTION 'F4IF_FIELD_VALUE_REQUEST'
           EXPORTING
                tabname     = 'DEMOF4HELP'
                fieldname   = 'CARRIER1'
                dynpprog    = progname
                dynpnr      = dynnum
                dynprofield = 'CARRIER'.
    ENDMODULE.
    MODULE value_connection INPUT.
      CALL FUNCTION 'DYNP_VALUES_READ'
           EXPORTING
                dyname             = progname
                dynumb             = dynnum
                translate_to_upper = 'X'
           TABLES
                dynpfields         = dynpro_values.
      READ TABLE dynpro_values INDEX 1 INTO field_value.
      SELECT  carrid connid
        FROM  spfli
        INTO  CORRESPONDING FIELDS OF TABLE values_tab
        WHERE carrid = field_value-fieldvalue.
      CALL FUNCTION 'F4IF_INT_TABLE_VALUE_REQUEST'
           EXPORTING
                retfield    = 'CONNID'
                dynpprog    = progname
                dynpnr      = dynnum
                dynprofield = 'CONNECTION'
                value_org   = 'S'
           TABLES
                value_tab   = values_tab.
    ENDMODULE.
    *POH gives you F1 documentation:*
    like:
    If data element supplement documentation is insufficient for your requirements, or you want to display help for program fields that you have not copied from the ABAP Dictionary, you can call dialog modules in the POH event:
    PROCESS ON HELP-REQUEST.
      FIELD  is defined in the ABAP program like a normal PAI module. The processing logic of the module must ensure that adequate help is displayed for the field in question. Instead of calling an extra screen with text fields, you should use one of the following function modules to display a suitable SAPscript document:
    HELP_OBJECT_SHOW_FOR_FIELD
    This function module displays the data element documentation for components of any structure or database table from the ABAP Dictionary. You pass the name of the component and structure or table to the import parameters FIELD and TABLE.
    HELP_OBJECT_SHOW
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    For further information about how to create SAPscript documents, refer to the  Documentation of System Objects documentation.
    Field help on screens.
    REPORT DEMO_DYNPRO_F1_HELP.
    DATA:  TEXT(30),
           VAR(4),
           INT TYPE I,
           LINKS TYPE TABLE OF TLINE,
           FIELD3, FIELD4.
    TABLES DEMOF1HELP.
    TEXT = TEXT-001.
    CALL SCREEN 100.
    MODULE CANCEL INPUT.
      LEAVE PROGRAM.
    ENDMODULE.
    MODULE F1_HELP_FIELD2 INPUT.
      INT = INT + 1.
      CASE INT.
        WHEN 1.
        VAR = '0100'.
        WHEN 2.
        VAR = '0200'.
        INT = 0.
      ENDCASE.
    ENDMODULE.
    MODULE F1_HELP_FIELD3 INPUT.
      CALL FUNCTION 'HELP_OBJECT_SHOW_FOR_FIELD'
           EXPORTING
                DOKLANGU                      = SY-LANGU
                DOKTITLE                      = TEXT-002
                CALLED_FOR_TAB                = 'DEMOF1HELP'
                CALLED_FOR_FIELD              = 'FIELD1'.
    ENDMODULE.
    MODULE F1_HELP_FIELD4 INPUT.
      CALL FUNCTION 'HELP_OBJECT_SHOW'
           EXPORTING
                DOKCLASS                      = 'TX'
                DOKLANGU                      = SY-LANGU
                DOKNAME                       = 'DEMO_FOR_F1_HELP'
                DOKTITLE                      = TEXT-003
           TABLES
                LINKS                         = LINKS.
    ENDMODULE.
    Regards,
    Renjith Michael

  • MAIN DIFFERENCES BETWEEN PARALLEL AND SEQUENTAIL PRCESSING???

    HI PALS,
    I WANT THE COMPLETE DIFFERENCES BETWEEN PARALLEL AND SEQUENTIAL PROCESSING!
    IN THE CONTEXT OF RFC.

    Hi
    Parallel Processing
    To achieve a balanced distribution of the system load, you can use destination additions to execute function modules in parallel tasks in any application server or in a predefined application server group of an SAP system.
    Parallel-processing is implemented with a special variant of asynchonous RFC. Itu2019s important that you use only the correct variant for your own parallel processing applications: the CALL FUNCTION STARTING NEW TASK DESTINATION IN GROUP keyword. Using other variants of asynchronous RFC circumvents the built-in safeguards in the correct keyword, and can bring your system to its knees
    Details are discussed in the following subsections:
    ·        Prerequisites for Parallel Processing
    ·        Function Modules and ABAP Keywords for Parallel Processing
    ·        Managing Resources in Parallel Processing
    Prerequisites for Parallel Processing
    Before you implement parallel processing, make sure that your application and your SAP system meet these requirements:
    ·        Logically-independent units of work:
    The data processing task that is to be carried out in parallel must be logically independent of other instances of the task. That is, the task can be carried out without reference to other records from the same data set that are also being processed in parallel, and the task is not dependent upon the results of others of the parallel operations. For example, parallel processing is not suitable for data that must be sequentially processed or in which the processing of one data item is dependent upon the processing of another item of the data.
    By definition, there is no guarantee that data will be processed in a particular order in parallel processing or that a particular result will be available at a given point in processing. 
    ·        ABAP requirements:
    ¡        The function module that you call must be marked as externally callable. This attribute is specified in the Remote function call supported field in the function module definition (transaction SE37).
    ¡        The called function module may not include a function call to the destination u201CBACK.u201D
    ¡        The calling program should not change to a new internal session after making an asynchronous RFC call. That is, you should not use SUBMIT or CALL TRANSACTION in such a report after using CALL FUNCTION STARTING NEW TASK.  
    ¡        You cannot use the CALL FUNCTION STARTING NEW TASK DESTINATION IN GROUP keyword to start external programs. 
    ·        System resources: 
    In order to process tasks from parallel jobs, a server in your SAP system must have at least 3 dialog work processes. It must also meet the workload criteria of the parallel processing system: Dispatcher queue less than 10% full, at least one dialog work process free for processing tasks from the parallel job.
    Function Modules and ABAP Keywords for Parallel Processing
    You can implement parallel processing in your applications by using the following function modules and ABAP keywords:
    ·        SPBT_INITIALIZE: Optional function module. 
    Use to determine the availability of resources for parallel processing. 
    You can do the following:
    ¡        check that the parallel processing group that you have specified is correct.
    ¡        find out how many work processes are available so that you can more efficiently size the packets of data that are to be processed in your data.
    ·        CALL FUNCTION Remotefunction STARTING NEW TASK Taskname DESTINATION IN GROUP:
    With this ABAP statement, you are telling the SAP system to process function module calls in parallel. Typically, youu2019ll place this keyword in a loop in which you divide up the data that is to be processed into work packets. You can pass the data that is to be processed in the form of an internal table (EXPORT, TABLE arguments). The keyword implements parallel processing by dispatching asynchronous RFC calls to the servers that are available in the RFC server group specified for the processing.
    Note that your RFC calls with CALL FUNCTION are processed in work processes of type DIALOG. The DIALOG limit on processing of one dialog step (by default 300 seconds, system profile parameter rdisp/max_wprun_time) applies to these RFC calls. Keep this limit in mind when you divide up data for parallel processing calls. 
    ·        SPBT_GET_PP_DESTINATION: Optional function module. 
    Call immediately after the CALL FUNCTION keyword to get the name of the server on which the parallel processing task will be run. 
    ·        SPBT_DO_NOT_USE_SERVER: Optional function module. 
    Excludes a particular server from further use for processing parallel processing tasks. Use in conjunction with SPBT_GET_PP_DESTINATION if you determine that a particular server is not available for parallel processing (for example, COMMUNICATION FAILURE exception if a server becomes unavailable).
    ·        WAIT: ABAP keyword
    WAIT UNTIL
    Required if you wish to wait for all of the asynchronous parallel tasks created with CALL FUNCTION to return. This is normally a requirement for orderly background processing. May be used only if the CALL FUNCTION includes the PERFORMING ON RETURN addition.
    ·        RECEIVE: ABAP keyword
    RECEIVE RESULTS FROM FUNCTION Remotefunction
    Required if you wish to receive the results of the processing of an asynchronous RFC. RECEIVE retrieves IMPORT and TABLE parameters as well as messages and return codes.
    Managing Resources in Parallel Processing
    You use the following destination additions to perform parallel execution of function modules (asynchronous calls) in the SAP system:
    In a predefined group of application servers:
    CALL FUNCTION Remotefunction STARTING NEW TASK Taskname
    DESTINATION IN GROUP Groupname
    In all currently available and active application servers:
    CALL FUNCTION Remotefunction STARTING NEW TASK Taskname
    DESTINATION IN GROUP DEFAULT
    Sequential Processing
    In the following cases, the system chooses sequential (non-parallel) processing:
    ●      In table RSADMIN, entry QUERY_MAX_WP_DIAG has value (column value) 1.
    ●      The entire query consists of one sub-access only.
    ●      The query is running in a batch process.
    ●      The query was started from the query monitor (transaction RSRT) using various debug options (for example, SQL query display, execution plan display). See, Dividing a MultiProvider Query into Sub-Queries.
    ●      The query requests non-cumulative key figures.
    ●      Insufficient dialog processes are available when the query is executed. These are required for parallel processing.
    ●      The query is configured for non-parallel processing.
    ●      You want to save the result of the query in a file or a table.
    In Release SAP NetWeaver 7.0, the system can efficiently manage the large intermediate results produced by parallel processing. In previous releases, the system terminated when it reached a particular intermediate result size and proceeded to read data sequentially. This is no longer the case. Therefore, the RSADMIN parameter that was used in previous releases for reading a MultiProvider sequentially is no longer used.
    Reward If Helpfull,
    Naresh

  • Difference between mailroutingsmarthost and daemon

    I would like to know the difference between mailroutingsmarthost and daemon usage. When to use mailroutingsmarthost and when to use daemon?
    Thanks in advance.

    MailRoutingSmarthost is placed in LDAP for a domain.
    Daemon keyword is for an entire channel, and is used in the imta.cnf
    LDAP entries require no restart.
    imta.cnf mods require both compile of new config and a restart of the dispatcher to take effect.

  • Difference between extends and implements

    hi
    i am new to java. i need to know the difference between extends class implement class.
    can anybody explain in simple words? i am new too oops concept also?
    what are the conditions to use extends class, implement and interface?
    class b extends a implements c
    i know class a is a super class and class b is a sub class.
    if class b extends class a means how should be the class a, what about the methods?
    and class a implements class c means what should be the conditions?
    i searched in Internet but the explanation is not very to me.can body explain me please?
    thank you

    sarcasteak wrote:
    Your class can implement an interface, which means it must use the methods defined in the interface.No, it doesn't need to use them. It needs to implement them. Or be declared abstract.
    Note that the methods in the interface are empty,No, they're not. They're abstract.
    // empty method
    void foo() {}
    // abstract method
    abstract void foo();(The abstract keyword is optional for interface methods, since they're all abstract.
    and you have to define what they do in your class that implements the interface.Just like they have to for abstract methods in a class you extend, if the child class is not declared abstract.
    There really isn't any difference between "extends" and "implements." There is no situation where you can choose. Any case where one is legal, only that one is legal. They could just as easily be a single keyword.
    Presumably the OP's real question is, "When do I use a class for a supertype vs. using an interface for a supertype?" The answer to that, of course, is:
    Use a class when at least some of the methods have valid default implementations. Use an interface when that is not the case. And of course the two are not mutually exclusive. It's quite common to do both.
    At the end of the day, an interface is really nothing more than a class that has no non-final or non-static member variables and whose instance methods are all abstract, and from which you can multiply inherit.
    Edited by: jverd on Feb 4, 2010 1:56 PM

  • Difference between Events and Photos

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    Can anyone simply explain the difference between "Events" and "Photos"? When I click on "Photos", it seems to open every folder of photos I moved over, is there any way to collapse all of these without having to collapse each individually?
    I am trying to organize folder and albums, a big task...but trying to figure out the difference between "Events" and "Photos" and the purpose/usage/advantage of each. They seem to be somewhat of a duplication.
    Nobody said the pc to mac migration would be simple...
    Thanks in advance.

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