LinkedList, sort method with Comparable class

I have created my own LinkedList class; named Linked (empty list) and LinkedNode. One of the method is sort() that use Comparable class. My problem is when I use my Linked class in my Library class (that uses Linked<Book> list = new Linked<Book>();) I face problem and the methods throw excpetion, and I discovered that this excpetion is from Comparable class.
The sort() method in Linked class:
public Linked<E> sort(){
          Linked<E> newList = new Linked<E>();
          System.out.println("Here is your prob");
          Comparable h = (Comparable)head;// head +compareTo
          System.out.println("Here is your prob");
          Linked<E> less = new Linked<E>();
          Linked<E> more = new Linked<E>();
          for(Linked<E> l = tail; !l.empty(); l=l.tail() ){
               if(h.compareTo(l.head())>0)
                    less=less.add(l.head());
               else
                    more=more.add(l.head());
          less=less.sort();
          more=more.sort();
          newList=less.join(more.add(head));
          return newList;
     }The sortCollection method in Library class:
public void sortCollection()throws NullPointerException{
list.sort(); } Also, I want to do my own Comparable class that switch between different sort modes.
Hope my question is clear.
Regards,

The exception is
java.lang.ClassCastException: Library.Book
     at Library.LinkedNode.sort(LinkedNode.java:58)
     at Library.BookLibrary.sortCollection(BookLibrary.java:145)
     at GUI.Projecc.actionPerformed(Projecc.java:351)
     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.dispatchEvent(Unknown Source)
     at java.awt.EventDispatchThread.pumpOneEventForHierarchy(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)

Similar Messages

What types of sort performed by sort method of Array class ?

I use normal bubble sort and method Array.sort() to sort some given data of an Array and then count the time.But Array.sort() method takes more time then normal bubble sort.
Can anybody tell me what types of sort performed by sort method of Array class?

I'm pretty sure that in eariler versions (1.2, 1.3
maybe?) List.sort's docs said it used quicksort. Or I
might be on crack.You are actually both correct, and wrong :)
From the documentation of the sort methods hasn't changed in 1.2 -> 1.4 (as far as I can notice), and the documentation for sort(Object[]) says (taken from JDK 1.2 docs):
"This sort is guaranteed to be stable: equal elements will not be reordered as a result of the sort.
The sorting algorithm is a modified mergesort (in which the merge is omitted if the highest element in the low sublist is less than the lowest element in the high sublist). This algorithm offers guaranteed n*log(n) performance, and can approach linear performance on nearly sorted lists."
So, how could you be correct? The documentation for e.g. sort(int[]) (and all other primities) says:
"Sorts the specified array of ints into ascending numerical order. The sorting algorithm is a tuned quicksort, adapted from Jon L. Bentley and M. Douglas McIlroy's "Engineering a Sort Function", Software-Practice and Experience, Vol. 23(11) P. 1249-1265 (November 1993). This algorithm offers n*log(n) performance on many data sets that cause other quicksorts to degrade to quadratic performance."
Your memory serves you well :)
/Kaj

Need help in compare method of Comparator class

I am writing a program that will display elements of a TreeMap in an order in which I want. By default the order is ascending. To change the order I need to override the compare method of the Comparator class.
I've done this in my code below.
I want to display keys with lower-case 1st and then those with upper-case.
Please help.
import java.util.*;
public class MyComparator implements Comparator {
public int compare(Object o1, Object o2) {
    String s1 = o1.toString();
    String s2 = o2.toString();
    return s1.compareTo(s2);
public static void main(String[] args) {
    Map names = new TreeMap(new MyComparator());
    names.put("a", new Integer(1435));
    names.put("b", new Integer(1110));
    names.put("A", new Integer(1425));
    names.put("B", new Integer(987));
    names.put("C", new Integer(1323));
    Set namesSet = names.keySet();
    Iterator iter = namesSet.iterator();
    while(iter.hasNext()) {
      String who = (String)iter.next();
      System.out.println(who + " => " +     names.get(who));
}

public int compare(Object o1, Object o2) {
    String s1 = o1.toString();
    String s2 = o2.toString();
    String ss1 = beginsWithLowerLetter(s1)? s1.toUpperCase() : s1.toLowerCase();
    String ss2 = beginsWithLowerLetter(s2)? s2.toUpperCase() : s2.toLowerCase();
    return ss1.compareTo(ss2);
}

Using common methods with abstract classes

hello everyone, i wanted to know if it is bad practice (i imagine it is) to place methods which will be used by multiple classes (computational methods) in an abstract class and mark them as static. When i do this they are always project wide utility classes which dont need an instantiation. When using any of these methods which are common to a project i can then just use..
Type result = ClassName.DoStaticMethod(...);Thanks for any input,
Dori
Edited by: Sir_Dori on Dec 8, 2008 2:01 AM

Depends on what the methods are meant to do, but I wouldn't make the class abstract. I would instead declare it to be final and have a private constructor.
Kaj
Ps. Take a look at the java.lang.Match class.

How to call a static method in a class if I have just the object?

Hello. I have an abstract class A where I have a static method blah(). I have 2 classes that extend class A called B and C. In both classes I override method blah(). I have an array with objects of type B and C.
For every instance object of the array, I'm trying to call the static method in the corresponding class. For objects of type B I want to call blah() method in B class and for objects of type C I want to call blah() method in C class. I know it's possible to call a static method with the name of the object, too, but for some reason (?) it calls blah() method in class A if I try this.
So my question is: how do I code this? I guess I need to cast to the class name and then call the method with the class name, but I couldn't do it. I tried to use getClass() method to get the class name and it works, but I didn't know what to do from here...
So any help would be appreciated. Thank you.

As somebody already said, to get the behavior you
want, make the methods non-static.You all asked me why I need that method to be
static... I'm not surprised to hear this question
because I asked all my friends before posting here,
and all of them asked me this... It's because some
complicated reasons, I doubt it.
the application I'm writing is
quite big...Irrelevant.
Umm... So what you're saying is there is no way to do
this with that method being static? The behavior you describe cannot be obtained with only static methods in Java. You'd have to explicitly determine the class and then explicitly call the correct class' method.

Help With Multiple Class Objects With Methods

I am dealing with multiple classes. I am wondering why I am getting an error on this line it's by the bottom
          obj1.array() = newArray[i];
It gives the array out of bounds. On another note I believe I can change obj1 to just like incomingArray if I wanted correct since it's just a reference because I should be able to do this method sort on any array.
method : selSort
input - none
output - void
This is where we sort the arary
Pseudocode Code:
1 Initialize variable oldlocation to hold spot of smallest number in original array
2 Initialize variable smallnumber to store smallest number in original array
3 Initialize new integer array
4 Set new array length to length of original array
5 Initialize variable length to store lengh of new array
6 For i = 0 and continue till i < new array length
6.1 Find smallest number in original array
6.2 Put the smallest number in new array
6.3 Remove smallest number from original array
7 Copy contents of new array that is sorted to original array
Basic concept is to repetitively find the smallest
(or largest) item in the original array. Once smallest
is found, move it to the next spot in a new array and
remove it from the old array.
public void selSort ()
     int oldlocation = 0;
     int smallnumber = 0;
     int [] newArray = obj1.array();
     newArray = new int [obj1.length()];
     int length = newArray.length;
     for (int i = 0; i < newArray.length; i++)
//          System.out.println("Test 1");
          newArray[i] = obj1.sortSmall();
//          System.out.println("Test 2");
          smallnumber = obj1.sortSmall();
//          System.out.println("This is the smallest number " + smallnumber);
          oldlocation = obj1.location(smallnumber);
//          System.out.println("This is the old location " + oldlocation);
//          System.out.println("Test 3");
          obj1.removeLocation(oldlocation);
//          System.out.println("Test 4");
     System.out.println();
     System.out.println("The sorted array looks like");
     for (int k = 0; k < newArray.length; k++)
          System.out.print(newArray[k] + " ");
     System.out.println();
     System.out.println();
     obj1.resize(newArray.length);
     for (int i = 0; i < newArray.length; i++)
          obj1.array()[i] = newArray[i];
     return;

method : selSort
input - none
output - void
This is where we sort the arary
Pseudocode Code:
1 Initialize variable oldlocation to hold spot of smallest number in original array
2 Initialize variable smallnumber to store smallest number in original array
3 Initialize new integer array
4 Set new array length to length of original array
5 Initialize variable length to store lengh of new array
6 For i = 0 and continue till i < new array length
6.1 Find smallest number in original array
6.2 Put the smallest number in new array
6.3 Remove smallest number from original array
7 Copy contents of new array that is sorted to original array
Basic concept is to repetitively find the smallest
(or largest) item in the original array. Once smallest
is found, move it to the next spot in a new array and
remove it from the old array.
public void selSort ()
     int oldlocation = 0;
     int smallnumber = 0;
     int [] newArray = obj1.array();
     newArray = new int [obj1.length()];
     int length = newArray.length;
     for (int i = 0; i < newArray.length; i++)
//          System.out.println("Test 1");
          newArray[i] = obj1.sortSmall();
//          System.out.println("Test 2");
          smallnumber = obj1.sortSmall();
//          System.out.println("This is the smallest number " + smallnumber);
          oldlocation = obj1.location(smallnumber);
//          System.out.println("This is the old location " + oldlocation);
//          System.out.println("Test 3");
          obj1.removeLocation(oldlocation);
//          System.out.println("Test 4");
     System.out.println();
     System.out.println("The sorted array looks like");
     for (int k = 0; k < newArray.length; k++)
          System.out.print(newArray[k] + " ");
     System.out.println();
     System.out.println();
     obj1.resize(newArray.length);
     for (int i = 0; i < newArray.length; i++)
          obj1.array() = newArray[i];
     return;

Using a Comparable Class with Treeset, creating counter in comparable clas

http://rafb.net/paste/results/jibQzk63.html - comparable http://rafb.net/paste/results/Noahue63.html - loading
http://rafb.net/paste/results/re1Swn60.html - contents of .txt file * sorry the paste is weird lol.
Trying to List word count in alphabetical order - Already did that
Having a counter so it counts the number of time that specfic word appeared in the txt file - This is my problem I don't know where to add the counter in my comparable class so it stores a number and adds everytime that same word appears. ex. "and 7" the word "and" appeared 7 times in the .txt file
so if some1 could help me, would be apperciated. I've like tried everything and getting the opposite results.

That's just the issue I'm having. My sample code functions as long as the parameterized type being compared isn't Comparable. For example, changing the type to A<Integer,String> works fine.
I think I may have discovered why this is the case. By declaring A<Comparable,String>, I am implying that the first parameterized type (call it T) is Comparable<T>. As a result, what I need is an A<Comparable<Comparable>, String>; that is, anything which is comparable must be able to be compared to the object. Since Integer is only Comparable<Integer>, it cannot be compared to all Comparable objects and therefore doesn't meet the requirements.
I'm not used to looking the other way on the inheritance tree. :)
The original trouble I had with this came from when I was passing a hash code generator into a piece of source and I needed to compare the hashes. The only guarantee I have regarding the hashes is that they are Comparable and I was putting them in a similar Pair structure. I then wanted to build a comparator to compare them but, since they're Comparable<?>, I can't know to what they can be compared... so I'll have to change the contract on the code. ;)
Thanks. Cheers. :)

Issue with CHECK_CHANGED_DATA method of CL_GUI_ALV_GRID class

HI,
I want to check whether my grid has any changes or not, for that i am using the CHECK_CHANGED_DATA method of CL_GUI_ALV_GRID class,
What i am doing is.... I am doing some changes in my grid data and clicking on SAVE . This time CHECK_CHANGED_DATA is saying the grid have changes ,and i am displaying a pop up whether to save the changes or not. And i am saving changes.
Till now Fine.
If i click on SAVE again CHECK_CHANGED_DATA is showing again the Grid has changes.
So how can i solve this problem.
Thanks in advance.

Hello Narendra
If you do not need to do any validations of the changed ALV list data then you can use a very simple approach which does not even require an event handler for event DATA_CHANGED.
The crucial part of the coding is shown below, followed by the entire sample report ZUS_SDN_ALV_EDITABLE_1A. Basically, the ALV list is stored as a "PBO" image of the data (GT_OUTTAB_PBO). And only if the user changed the data (i.e. GT_OUTTAB_PBO <> GT_OUTTAB) the save option including the popup is executed.
*&      Module USER_COMMAND_0100 INPUT
*       text
MODULE user_command_0100 INPUT.
" NOTE: retrieve changed data from frontend (grid control) into
"       the backend (itab in ABAP)
go_grid->check_changed_data( ).
CASE gd_okcode.
    WHEN 'BACK' OR
         'EXIT' OR
         'CANC'.
      SET SCREEN 0. LEAVE SCREEN.
    WHEN 'SAVE'.
      IF ( gt_outtab = gt_outtab_pbo ).
        MESSAGE 'No data changed' TYPE 'S'.
      ELSE.
        CLEAR: gd_answer.
        CALL FUNCTION 'POPUP_TO_CONFIRM'
          EXPORTING
*             TITLEBAR                    = ' '
*             DIAGNOSE_OBJECT             = ' '
            text_question               = 'Save data?'
          IMPORTING
            answer                      = gd_answer
*           TABLES
*             PARAMETER                   =
          EXCEPTIONS
            text_not_found              = 1
            OTHERS                      = 2.
        IF sy-subrc <> 0.
*       MESSAGE ID SY-MSGID TYPE SY-MSGTY NUMBER SY-MSGNO
*               WITH SY-MSGV1 SY-MSGV2 SY-MSGV3 SY-MSGV4.
        ENDIF.
        IF ( gd_answer = '1' ). " yes
          MESSAGE 'Data successfully saved' TYPE 'S'.
          gt_outtab_pbo = gt_outtab. " update PBO data !!!
        ELSE.
          MESSAGE 'Action cancelled by user' TYPE 'S'.
        ENDIF.
      ENDIF.
    WHEN OTHERS.
ENDCASE.
CLEAR: gd_okcode.
ENDMODULE.                 " USER_COMMAND_0100 INPUT
*& Report ZUS_SDN_ALV_EDITABLE
* Flow logic of screen '100' (no elements, ok-code => gd_okcode ):
**PROCESS BEFORE OUTPUT.
** MODULE STATUS_0100.
**PROCESS AFTER INPUT.
** MODULE USER_COMMAND_0100.
REPORT zus_sdn_alv_editable_1a.
TYPE-POOLS: abap.
CONSTANTS:
gc_tabname       TYPE tabname VALUE 'KNB1'.
TYPES: BEGIN OF ty_s_outtab.
INCLUDE TYPE knb1.
TYPES: END OF ty_s_outtab.
TYPES: ty_t_outtab    TYPE STANDARD TABLE OF ty_s_outtab
                      WITH DEFAULT KEY.
DATA:
gd_okcode        TYPE ui_func,
gd_repid         TYPE syst-repid,
gt_fcat          TYPE lvc_t_fcat,
gs_layout        TYPE lvc_s_layo,
gs_variant       TYPE disvariant,
go_docking       TYPE REF TO cl_gui_docking_container,
go_grid          TYPE REF TO cl_gui_alv_grid.
DATA:
gs_outtab        TYPE ty_s_outtab,
gt_outtab        TYPE ty_t_outtab,
gt_outtab_pbo    TYPE ty_t_outtab.
DATA:
gd_answer        TYPE c.
START-OF-SELECTION.
SELECT * FROM (gc_tabname) INTO TABLE gt_outtab UP TO 99 ROWS.
gt_outtab_pbo = gt_outtab. " set PBO data
PERFORM init_controls.
* ok-code field = GD_OKCODE
CALL SCREEN '0100'.
END-OF-SELECTION.
*&      Form INIT_CONTROLS
*       text
* --> p1        text
* <-- p2        text
FORM init_controls .
* Create docking container
CREATE OBJECT go_docking
    EXPORTING
      parent = cl_gui_container=>screen0
      ratio = 90
    EXCEPTIONS
      OTHERS = 6.
IF sy-subrc <> 0.
*   MESSAGE ID SY-MSGID TYPE SY-MSGTY NUMBER SY-MSGNO
*              WITH SY-MSGV1 SY-MSGV2 SY-MSGV3 SY-MSGV4.
ENDIF.
* Create ALV grid
CREATE OBJECT go_grid
    EXPORTING
      i_parent = go_docking
    EXCEPTIONS
      OTHERS   = 5.
IF sy-subrc <> 0.
*   MESSAGE ID SY-MSGID TYPE SY-MSGTY NUMBER SY-MSGNO
*              WITH SY-MSGV1 SY-MSGV2 SY-MSGV3 SY-MSGV4.
ENDIF.
" NOTE: not required
* set handler:
*    lcl_eventhandler=>handle_data_changed for go_grid.
* Build fieldcatalog and set hotspot for field KUNNR
PERFORM build_fieldcatalog.
PERFORM set_layout_and_variant.
* Display data
CALL METHOD go_grid->set_table_for_first_display
    EXPORTING
      is_layout       = gs_layout
      is_variant      = gs_variant
      i_save          = 'A'
    CHANGING
      it_outtab       = gt_outtab
      it_fieldcatalog = gt_fcat
    EXCEPTIONS
      OTHERS          = 4.
IF sy-subrc <> 0.
*   MESSAGE ID SY-MSGID TYPE SY-MSGTY NUMBER SY-MSGNO
*              WITH SY-MSGV1 SY-MSGV2 SY-MSGV3 SY-MSGV4.
ENDIF.
* NOTE:
* Documenation of I_SAVE ("An Easy Reference for ALV Grid Control")
*I_SAVE
*Determines the options available to the user for saving a layout:
*? 'X': global saving only
*? 'U': user-specific saving only
*? 'A': corresponds to 'X' and 'U'
*? SPACE: no saving
* Link the docking container to the target dynpro
gd_repid = syst-repid.
CALL METHOD go_docking->link
    EXPORTING
      repid                       = gd_repid
      dynnr                       = '0100'
*      CONTAINER                   =
    EXCEPTIONS
      OTHERS                      = 4.
IF sy-subrc <> 0.
*   MESSAGE ID SY-MSGID TYPE SY-MSGTY NUMBER SY-MSGNO
*              WITH SY-MSGV1 SY-MSGV2 SY-MSGV3 SY-MSGV4.
ENDIF.
ENDFORM.                    " INIT_CONTROLS
*&      Module STATUS_0100 OUTPUT
*       text
MODULE status_0100 OUTPUT.
SET PF-STATUS 'STATUS_0100'.
* SET TITLEBAR 'xxx'.
ENDMODULE.                 " STATUS_0100 OUTPUT
*&      Module USER_COMMAND_0100 INPUT
*       text
MODULE user_command_0100 INPUT.
" NOTE: retrieve changed data from frontend (grid control) into
"       the backend (itab in ABAP)
go_grid->check_changed_data( ).
CASE gd_okcode.
    WHEN 'BACK' OR
         'EXIT' OR
         'CANC'.
      SET SCREEN 0. LEAVE SCREEN.
    WHEN 'SAVE'.
      IF ( gt_outtab = gt_outtab_pbo ).
        MESSAGE 'No data changed' TYPE 'S'.
      ELSE.
        CLEAR: gd_answer.
        CALL FUNCTION 'POPUP_TO_CONFIRM'
          EXPORTING
*             TITLEBAR                    = ' '
*             DIAGNOSE_OBJECT             = ' '
            text_question               = 'Save data?'
*             TEXT_BUTTON_1               = 'Ja'(001)
*             ICON_BUTTON_1               = ' '
*             TEXT_BUTTON_2               = 'Nein'(002)
*             ICON_BUTTON_2               = ' '
*             DEFAULT_BUTTON              = '1'
*             DISPLAY_CANCEL_BUTTON       = 'X'
*             USERDEFINED_F1_HELP         = ' '
*             START_COLUMN                = 25
*             START_ROW                   = 6
*             POPUP_TYPE                  =
*             IV_QUICKINFO_BUTTON_1       = ' '
*             IV_QUICKINFO_BUTTON_2       = ' '
          IMPORTING
            answer                      = gd_answer
*           TABLES
*             PARAMETER                   =
          EXCEPTIONS
            text_not_found              = 1
            OTHERS                      = 2.
        IF sy-subrc <> 0.
*       MESSAGE ID SY-MSGID TYPE SY-MSGTY NUMBER SY-MSGNO
*               WITH SY-MSGV1 SY-MSGV2 SY-MSGV3 SY-MSGV4.
        ENDIF.
*         Triggers PAI of the dynpro with the specified ok-code
        IF ( gd_answer = '1' ). " yes
          MESSAGE 'Data successfully saved' TYPE 'S'.
          gt_outtab_pbo = gt_outtab. " update PBO data !!!
        ELSE.
          MESSAGE 'Action cancelled by user' TYPE 'S'.
        ENDIF.
      ENDIF.
    WHEN OTHERS.
ENDCASE.
CLEAR: gd_okcode.
ENDMODULE.                 " USER_COMMAND_0100 INPUT
*&      Form BUILD_FIELDCATALOG
*       text
* --> p1        text
* <-- p2        text
FORM build_fieldcatalog .
* define local data
DATA:
    ls_fcat        TYPE lvc_s_fcat.
CALL FUNCTION 'LVC_FIELDCATALOG_MERGE'
    EXPORTING
*     I_BUFFER_ACTIVE              =
      i_structure_name             = gc_tabname
*     I_CLIENT_NEVER_DISPLAY       = 'X'
*     I_BYPASSING_BUFFER           =
*     I_INTERNAL_TABNAME           =
    CHANGING
      ct_fieldcat                  = gt_fcat
    EXCEPTIONS
      inconsistent_interface       = 1
      program_error                = 2
      OTHERS                       = 3.
IF sy-subrc <> 0.
* MESSAGE ID SY-MSGID TYPE SY-MSGTY NUMBER SY-MSGNO
*         WITH SY-MSGV1 SY-MSGV2 SY-MSGV3 SY-MSGV4.
ENDIF.
ls_fcat-edit = abap_true.
MODIFY gt_fcat FROM ls_fcat
      TRANSPORTING edit
    WHERE ( key NE abap_true ).
ENDFORM.                    " BUILD_FIELDCATALOG
*&      Form SET_LAYOUT_AND_VARIANT
*       text
* --> p1        text
* <-- p2        text
FORM set_layout_and_variant .
CLEAR: gs_layout,
         gs_variant.
gs_layout-cwidth_opt = abap_true.
gs_layout-zebra      = abap_true.
gs_variant-report = syst-repid.
gs_variant-handle = 'GRID'.
ENDFORM.                    " SET_LAYOUT_AND_VARIANT
Regards
Uwe

Can't fill ByteArray in EJB-Method with generated Model-Class from WD-Model

Hello everybody,
i try to call an ejb-method with data from an FileUpload-UI-Element in WD. The EJB-Method is receiving the byte-data to create a document in KM via a Web-Service.
The ebj-methid has the following signature:
public FObject putFileDataSimple (byte [] btContent, String fullFileName, String username, String password)
After importing the Model and creating a context node i have the following structure:
Request_X_putFileDataSimple
+---btContent (Node)
      +-- item
+ fullFileName
+ username
+ password
btContent is of the generated Type Byte_Item, which is itself a generated Model-Class of modelClassType ARRAY
item is of Type byte
But i simply have problems to fill the context node (or the binded model-object). i tried different ways and looked at thread [https://www.sdn.sap.com/irj/scn/thread?messageID=1954223] but i cant get it work.
So my Method in WD looks like this to fill the structure and start the ejb-method:
public boolean putKMDataSimple( com.sap.tc.webdynpro.services.sal.datatransport.api.IWDResource fin ) {
try
wdContext.currentRequest_X_putFileDataSimpleElement().setFullFileName("abc");
wdContext.currentRequest_X_putFileDataSimpleElement().setUsername("def");
wdContext.currentRequest_X_putFileDataSimpleElement().setPassword("xxx");
byte[] buffer = new byte[1];
InputStream in = fin.read(false);
int i = 1;
int j = 0;
while (i!=-1)
     i = in.read(buffer);
     if (i!=-1)
       Byte_Item bi = new Byte_Item(mAlf);     // mAlf ist global defined Model-Class-Instance
       bi.setItem(buffer[0]);
        wdContext.currentRequest_X_putFileDataSimpleElement().modelObject().addBtContent(bi);
wdContext.currentRequest_X_putFileDataSimpleElement().modelObject().execute();
Doing this results in Error-Messages like:
Model-Object is not a complex type for every byte added this way.
And finally an IllegalArgumentException at java.lang.reflect.Array.set(Native Method)
The second way i tried is:
public boolean putKMDataSimple( com.sap.tc.webdynpro.services.sal.datatransport.api.IWDResource fin ) {
try
wdContext.currentRequest_X_putFileDataSimpleElement().setFullFileName("abc");
wdContext.currentRequest_X_putFileDataSimpleElement().setUsername("def");
wdContext.currentRequest_X_putFileDataSimpleElement().setPassword("xxx");
byte[] buffer = new byte[1];
ArrayList<Byte> btlist = new ArrayList<Byte>();
InputStream in = fin.read(false);
int i = 1;
int j = 0;
while (i!=-1)
     i = in.read(buffer);
     if (i!=-1)
          btList.add(buffer[0]);
wdContext.currentRequest_X_putFileDataSimpleElement().modelObject().setBtContent(btList);
wdContext.currentRequest_X_putFileDataSimpleElement().modelObject().execute();
Trying so results in:
java.lang.ClassCastException: class java.lang.Byte:null incompatible with interface com.sap.tc.cmi.model.ICMIModelClass:library:com.sap.tc.cmi(at-sign)[email protected]@alive
whenn calling the setBtContent Method
I don't what to do now to fill the context/model-object the right way.
Any helpfull hints are very welcome
Edited by: Matthias Hayk on Dec 1, 2008 5:51 PM
Edited by: Matthias Hayk on Dec 2, 2008 10:56 AM

Ok Vesselin and thanx for your idea,
so i adapted the source in the way you told like the following:
                 ArrayList<Byte_Item> btlist = new ArrayList<Byte_Item>();
                 byte[] buffer = new byte[1];
                 InputStream in = fin.read(false);
                 int i = 1;
                 int j = 0;
                 while (i!=-1)
                      i = in.read(buffer);
                      if (i!=-1)
                           // Byte gelesen
                           Byte_Item bi = new Byte_Item(mAlf);
                           bi.setItem(buffer[0]);
                           btlist.add(bi);
                           j++;
                 wdContext.currentRequest_X_putFileDataSimpleElement().modelObject().setBtContent(btlist);
                 wdContext.currentRequest_X_putFileDataSimpleElement().modelObject().execute();
This results also in the following Exception when exceuting the WS-proxy:
execute
[EXCEPTION]
java.lang.IllegalArgumentException
at java.lang.reflect.Array.set(Native Method)
at com.sap.tc.webdynpro.model.ejb.model.EJBGenericModelClassExecutable.getInputParameters(EJBGenericModelClassExecutable.java:215)
at com.sap.tc.webdynpro.model.ejb.model.EJBGenericModelClassExecutable.execute(EJBGenericModelClassExecutable.java:112)

Getting problem with DOMImplementation classes method getFeature() method

hi
getting problem with DOMImplementation classes method getFeature() method
Error is cannot find symbol getFeature()
code snippet is like...
private void saveXml(Document document, String path) throws IOException {
DOMImplementation implementation = document.getImplementation();
DOMImplementationLS implementationLS = (DOMImplementationLS) (implementation.getFeature("LS", "3.0"));
LSSerializer serializer = implementationLS.createLSSerializer();
LSOutput output = implementationLS.createLSOutput();
FileOutputStream stream = new FileOutputStream(path);
output.setByteStream(stream);
serializer.write(document, output);
stream.close();
problem with getFeature() method

You are probably using an implementation of DOM which does not implement DOM level-3.

Problem with getState() method in Thread class

Can anyone find out the problem with the given getState() method:
System.out.println("The state of Thread 1: "+aThread.getState());
The Error message is as follows:
threadDemo.java:42: cannot resolve symbol
symbol : method getState ()
location: class incrementThread
System.out.println("The state of Thread 1: "+aThread.getState())
^
1 error

the api doc shows Since: 1.5
You do use Java 5...if not... it's not available.

How do I call methods with the same name from different classes

I have a user class which needs to make calls to methods with the same name but to ojects of a different type.
My User class will create an object of type MyDAO or of type RemoteDAO.
The RemoteDAO class is simply a wrapper class around a MyDAO object type to allow a MyDAO object to be accessed remotely. Note the interface MyInterface which MyDAO must implement cannot throw RemoteExceptions.
Problem is I have ended up with 2 identical User classes which only differ in the type of object they make calls to, method names and functionality are identical.
Is there any way I can get around this problem?
Thanks ... J
My classes are defined as followes
interface MyInterface{
     //Does not and CANNOT declare to throw any exceptions
    public String sayHello();
class MyDAO implements MyInterface{
   public String sayHello(){
          return ("Hello from DAO");
interface RemoteDAO extends java.rmi.Remote{
     public String sayHello() throws java.rmi.RemoteException;
class RemoteDAOImpl extends UnicastRemoteObject implements RemoteDAO{
     MyDAO dao = new MyDAO();
    public String sayHello() throws java.rmi.RemoteException{
          return dao.sayHello();
class User{
   //MyDAO dao = new MyDAO();
   //OR
   RemoteDAO dao = new RemoteDAO();
   public void callDAO(){
          try{
          System.out.println( dao.sayHello() );
          catch( Exception e ){
}

>
That's only a good idea if the semantics of sayHello
as defined in MyInterface suggest that a
RemoteException could occur. If not, then you're
designing the interface to suit the way the
implementing classes will be written, which smells.
:-)But in practice you can't make a call which can be handled either remotely or locally without, at some point, dealing with the RemoteException.
Therefore either RemoteException must be part of the interface or (an this is probably more satisfactory) you don't use the remote interface directly, but MyInterface is implemented by a wrapper class which deals with the exception.

Sorting with Comparator, wrong order?

Hello,
i've a string array, and every string in this array in form of "Firstname [MiddleName] LastName". After i sort the array i get "List A" below, but i expect to get "List B". All "Alp"s must be together like dictionary order, isn't it? What cause this?
Regards,
List A:
Alp BBBBB
Alper KKKKK
Alper SSSSSS
Alp KKKKKKK
Alp OOOO
Alp ÖÖÖÖÖÖÖÖÖ
Alptuğ VVVVV
Alp YYYYY KKKKK
Alp YYYYYYYYYY
List B
Alp BBBBB
Alp KKKKKKK
Alp OOOO
Alp ÖÖÖÖÖÖÖÖÖ
Alp YYYYY KKKKK
Alp YYYYYYYYYY
Alper KKKKK
Alper SSSSSS
Alptuğ VVVVV
Code
import java.text.Collator;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.Comparator;
import java.util.List;
import java.util.Locale;
public class sort {
    static final Comparator<String> x = new Comparator<String>() {
        public int compare(String o1, String o2) {
            return Collator.getInstance(new Locale("tr", "TR")).compare(o1, o2);
    public static void main(String[] args) {
        String[] snames={
                 "Alp BBBBB",
                 "Alper KKKKK",
                 "Alper SSSSSS",
                 "Alp KKKKKKK",
                 "Alp OOOO",
                 "Alp ÖÖÖÖÖÖÖÖÖ",
                 "Alptuğ VVVVV",
                 "Alp YYYYY KKKKK",
                 "Alp YYYYYYYYYY"};
        List lsnames=Arrays.asList(snames);
        Collections.sort(lsnames, x);
        System.out.println(lsnames.toString().replaceAll(",", "\n"));
}

static final Comparator<String> x = new Comparator<String>()
        final private Collator collator = Collator.getInstance(new Locale("tr", "TR"));
        final private Pattern splitterPattern = Pattern.compile("\\s+");
        public int compare(String o1, String o2)
            try
                final String[] fields1 = splitterPattern.split(o1, 2);
                final String[] fields2 = splitterPattern.split(o2, 2);
                for (int i = 0; i < 2; i++)
                    final int v = collator.compare(fields1, fields2[i]);
if (v != 0)
return v;
} catch (Exception e)
// Possibly nothing to do here but, depending on how
// fatal one views it, one could throw
// an unchecked exception, just print a stack
// trace or totally ignore the exception.
// Since this is probably a system error, my
// preference is for
throw new Error("Problem in comparator", e);
return -1;
public static void main(String[] args)
String[] snames =
"Alp BBBBB",
"Alper KKKKK",
"Alper SSSSSS",
"Alp KKKKKKK",
"Alp OOOO",
"Alp ÖÖÖÖÖÖÖÖÖ",
"Alptuğ VVVVV",
"Alp YYYYY KKKKK",
"Alp YYYYYYYYYY"
List<String> lsnames = Arrays.asList(snames);
Collections.sort(lsnames, x);
System.out.println(lsnames.toString().replaceAll(",", "\n"));
}Edited by: sabre150 on Jan 6, 2009 10:37 AM

Inaccessible with local variable(non-final) via method local inner class

Hi All,
Usually local variables, including automatic final variable live on the stack and objects & instanace variables live on the heap.The contracts for using the method local inner class should allow merely method final variable, not non-final stack variable.
Can anyone please clarify me ,behind the scene what is actual fact why method inner class should not access the stack(method) variable and only allow final variable?
Is anything correlated with the stack and heap aspects?
Thanks,
Stalin.G

[email protected] wrote:
...behind the scene what is actual fact why method inner class should not access the stack(method) variable and only allow final variable?...explained by dcminter and Jardium in [an older thread|http://forums.sun.com/thread.jspa?messageID=10694240#10694240|http://forums.sun.com/thread.jspa?messageID=10694240#10694240]:
...Final variables are copied into inner classes - that's why they have to be declared final; to avoid the developer making an incorrect assumption that the local variable can be modified and have the change reflected in the copy.
When a local class uses a local variable, it doesn't actually use the variable. Instead, it takes a copy of the value which is contained in the variable at the moment the class is instantiated. It's like passing the variable to a constructor of the class, except that you do not actually declare any such constructor in your code.
To avoid messy execution flows to be present in a Java method, the Java language authors thought it was better to allow a single value to be present in such a variable throughout all its life. Thus, the variable has to be declared final.
...HTH

Issue with close() method of BufferedReader class and FileInputStream class

I have written the following code to a text file, called hello,txt from Windows. Everything works fine but I am trying to figure out whether calling of close() method of aforemetioned class is appropriate or necessary thing to do.
Here are the questions:
1. Is it necessary to call close method in this senario? And why? [it seems to me that everything gets cleaned up automatically anyways at the end of each call to the method when called from main()]
2. If the answer for No.1 is yes, then in which order each close method should be called? Or, does the order of calling close method matter anyways?
3. Is the reason for why in No.1 is that because calling close method on each object is a necessary step to do when dealing with mutli-thread?
Thanks for your help in advance!
      * Below is an example to clarify my questions
     void readWinFile() {
          File objFile = new File("hello.txt");
          FileInputStream fileStream = null;
          BufferedReader bfReader = null;
          try {
               fileStream = new FileInputStream(objFile);
               bfReader = new BufferedReader(
                                  new InputStreamReader(fileStream, "MS932"));
               int tmp;
               while ((tmp = bfReader.read()) != -1) {
                    System.out.print((char)tmpLine);
          } catch (FileNotFoundException e) {
               System.err.printf("File: %s Not Found @ DIR = %s",
                                   objFile.getName(), objFile.getParent());
          } catch (UnsupportedEncodingException e) {
               System.err.printf("Internal failure: %s", e);
          } catch (IOException e) {
               System.err.printf("File: %s close failure", objFile.getName());
*          } finally {*
*               if (bfReader != null) {*
*                    try {*
*                         bfReader.close();*
*                    } catch (IOException e) {*
*                         e.printStackTrace();*
*               if (fileStream != null) {*
*                    try {*
*                         fileStream.close();*
*                    } catch (IOException e) {*
*                         e.printStackTrace();*
}Edited by: Jay-K on Feb 14, 2010 8:50 PM
Edited by: Jay-K on Feb 14, 2010 8:52 PM

Hello CeciNEstPasUnProgrammeur,
Thank you for taking your time and doing all these write-up for me.
CeciNEstPasUnProgrammeur wrote:
Pretty much every native resource, most notably DB connections because those even remain open after the client process terminates. But ports or file handlers are similar; note that a JVM does not necessarily terminate just because you close your program in "extreme cases" (shared use of JVM). In an app server this is certainly never the way. And even if it does, as long as your app is running, the stuff is certainly never released.What you meant is that if my app runs on an app server, which shared the use of JVM with multiple apps, without properly closing ports or file handlers could cause JVM to keep retaining the native resource allocated for my app. In case of that, the resource leaks would occur.
On the other hand, if my app runs on an app server, which do not share the use of JVM, the leaks would be less likely to happen even if the ports or file handlers are not manually closed. (It could be a very poor design but technically I could reply on their finalizers to clean up the mess)
>
Another misconception seems to be that objects are automatically GCed the moment they run out of scope. This is not true.Is there any documentation somewhere that you could refer me to? I would like to figure out why objects are not auto-GCed when they run out of their scope.
>
And lastly, objects should not rely on their finalizers to release native resources, and should rather provide close/release methods. This is a common paradigm, and that's also why releasing the file handle won't work by simply letting the reader instance run out of scope. Nobody notifies the underlying OS.I see, so the JVM here interacts with the underlying OS to acquire sufficient native resource for its apps to run. Without explicit closing, which would make JVM not to notify underlying OS to release acquired resource. Am I on the ball here?
Thanks,
Jay

LinkedList, sort method with Comparable class

Similar Messages

Maybe you are looking for