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How to save select checkbox items to an XML file in Java?

Hi,
I have java code and this code creates GUI. In this GUI. I have check boxes in a Tree.

The thing that I would like to do is to save the selected check box items to an XML file.

This is the class and the methods that I use to create the tree with check boxes:

public class CheckListTree {
    private Tree tree;
    private static CheckListTree instance = null;
   
    
    private CheckListTree() {
    }
    
    public static CheckListTree getInstance()
    {
        if (instance == null) {
            instance = new CheckListTree();
        }
        //System.out.println("instance: " + instance);
        return instance;
    }
    
    
    public void unselectAll (){
        System.out.println("tree: " + tree);
        for (TreeItem item : tree.getItems()) {   
            //System.out.println("item: " + item);
            checkItems(item, false);
        }
        
    }
    
    public void checkPath(TreeItem item, boolean checked, boolean grayed) {
        if (item == null) return;
        if (grayed) {
            checked = true;
        } else {
            int index = 0;
            TreeItem[] items = item.getItems();
            while (index < items.length) {
                TreeItem child = items[index];
                if (child.getGrayed() || checked != child.getChecked()) {
                    checked = grayed = true;
                    break;
                }
                index++;
            }
        }
        item.setChecked(checked);
        item.setGrayed(grayed);
        checkPath(item.getParentItem(), checked, grayed);
    }

    public void checkItems(TreeItem item, boolean checked) {
        item.setGrayed(false);
        item.setChecked(checked);
        TreeItem[] items = item.getItems();
        for (int i = 0; i < items.length; i++) {
            checkItems(items[i], checked);
        }
    }

    public void createCheckListTree(Composite compTab2, GridData layoutData, List<HashMap<Integer, String>> checkList)  {
            tree = new Tree(compTab2, SWT.BORDER | SWT.CHECK);
            tree.setLayoutData(layoutData);
            tree.addListener(SWT.Selection, new Listener() {
                public void handleEvent(Event event) {
                    if (event.detail == SWT.CHECK) {
                        TreeItem item = (TreeItem) event.item;
                        boolean checked = item.getChecked();
                        checkItems(item, checked);
                        checkPath(item.getParentItem(), checked, false);
                    }
                }
            });
                  
            
            TreeItem item_Standards = new TreeItem(tree, SWT.NONE);
            item_Standards.setText("My List");
            
            Iterator<HashMap<Integer, String>> checkListIter = checkList.iterator();
            while(checkListIter .hasNext()) {
              HashMap<Integer, String> amap =   (HashMap<Integer, String>) checkListIter .next();
              Set<?> keysetString = (Set<?>) amap .keySet();
              Iterator<?> iter = keysetString.iterator();
              while( iter.hasNext() ) {
                Integer keyVal = (Integer) iter.next();
                //System.out.println("keyVal " + keyVal);
                String valFromKey = amap.get(keyVal);
                //System.out.println("valFromKey " + valFromKey);
                TreeItem item_Substandards = new TreeItem(item_Standards, SWT.NONE);
                item_Substandards.setText(valFromKey);
              } 
            }
    } 
    
    public void saveCheckedList2XML(){
    //HERE I WANT TO SAVE THE SELECTED ITEMS TO A PLACE of USER'S choice   
        
    }

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This is the listener I use for this button:

        }else if(toolItem == Gui.item222){
            CheckListTree.getInstance().saveCheckedList2XML();

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Can you please help me how I can do it in my code above?

Thanks

Tolgar

ASKER

Actually, I made some change in the structure:

The toolbar listener will be like this:

        }else if(toolItem == Gui.item222){
            FileDialog dlg = new FileDialog(shell);
            String file = dlg.open();
            //System.out.println("chosen file : " + file);
            if (file!=null && !file.equals("")){
                CheckListTree.getInstance().getCheckedStandards(file);
            }

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And the methods in the CheckListTree class will be as the following:

    public void write2XML(String content, String file) {
        //HERE WE WILL WRITE THE CONTENT TO AN XML FILE
    }
    
    public void getCheckedStandards(String file){
        //HERE WE WILL GET THE LIST OF CHECKED ITEMS FROM THE TREE
        
        write2XML(content, file);              
    }

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Tolgar

ASKER

so, I did the getCheckedStandards method as shown below:

    public void write2XML(TreeItem[] content, String fileName) {
        
    }
    
    public void getCheckedStandards(String file){
        TreeItem[] items = tree.getSelection();
        
        for (int i = 0; i < items.length; i++) {
            TreeItem[] child = items[i].getItems();
            for (int index=0; index < child.length; index++) { 
                if (child[index].getChecked()) {
                    System.out.println("item: " + index + ": " + child[index].getText());
                }
            }
        }
        //write2XML(item, file);              
    }

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Can you please show me how I can do write2XML method?

Thanks,

ASKER CERTIFIED SOLUTION

mccarl

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Tolgar

ASKER

The tree (with checkboxes on the left of each item including Employees. x refers to a check box) looks like this:

x Employees
   x Jack
   x Phil
   x John
   x Susan
   x Jeff

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The XML will be like this

<?xml version="1.0" encoding="UTF-8" standalone="no"?>
<Company>
<Employees>
<Name>
Jack
</Name>
<Name>
Phil
</Name>
<Name>
John
</Name>
<Name>
Susan
</Name>
Jeff
</Employees>
</Company>

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Tolgar

ASKER

The "Employees" node comes from items ith element that I mentioned in my previous post (ID: 39468335). After line 8 in that post, items ( in this case it will be items 0th because there is nothing else other than "employees" at that level), will be written maybe to an hash array and then child[index].getText() will be written to the same hash array at line 12 in the same code that I posted.

Then write2XML will be called with inputs arguments of this hash array and the file.

And, the sudo code will be like this:

    public void write2XML(TreeItem[] content, String fileName) {
        
    }
    
    public void getCheckedStandards(String file){
        TreeItem[] items = tree.getSelection();
        
        for (int i = 0; i < items.length; i++) {
            //IN HERE, WRITE items[i] node to an hash array in here at the top level. 
            //In the example xml, this will be the "Employees" node.
            TreeItem[] child = items[i].getItems();
            for (int index=0; index < child.length; index++) { 
                if (child[index].getChecked()) {
                    // IN HERE, WRITE the name node with the value
                   // of child[index].getText() in the hash array as the child of the "Employees" node. In the example xml, the values of Jack, Phil,
                   //John, Susan, Jeff will be put in the name nodes                 
                    System.out.println("item: " + index + ": " + child[index].getText());
                }
            }
        }    
          //THEN CALL write2XML method with the input values of hash array and file.
    }

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Then we need to loop through the hash array in write2XML while writing to the XML file.

And for write2XML, I have this code in place but it only writes one input to the XML. It does not loop through an hash array:

    public void write2XML(String content, String file) {

        try {
   
          DocumentBuilderFactory docFactory = DocumentBuilderFactory.newInstance();
          DocumentBuilder docBuilder = docFactory.newDocumentBuilder();
   
          // root elements
          Document doc = docBuilder.newDocument();
          Element rootElement = doc.createElement("Company");
          doc.appendChild(rootElement);
   
          // staff elements
          Element staff = doc.createElement("Employees");
          rootElement.appendChild(staff);
   
          // firstname elements
          Element firstname = doc.createElement("Name");
          firstname.appendChild(doc.createTextNode(content));
          staff.appendChild(firstname);

   
          // write the content into xml file
          TransformerFactory transformerFactory = TransformerFactory.newInstance();
          Transformer transformer = transformerFactory.newTransformer();
          DOMSource source = new DOMSource(doc);
          StreamResult result = new StreamResult(file);
   
          transformer.transform(source, result);
   
          System.out.println("File saved!");
   
        } catch (ParserConfigurationException pce) {
            pce.printStackTrace();
        } catch (TransformerException tfe) {
            tfe.printStackTrace();
        }
    }

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How can I do this in Java with these codes?

Tolgar

ASKER

Ok. I did something to solve this question but I am getting the following error:

Exception in thread "main" java.lang.ClassCastException: org.eclipse.swt.widgets.TreeItem cannot be cast to java.lang.String

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And this is the code that I used:

    public void write2XML(Map<Integer, TreeItem> checkListMap, Map<Integer, String> checkNameMap, String file) {
        Iterator<Entry<Integer, TreeItem>> it_checkListMap = checkListMap.entrySet().iterator();
        Iterator<Entry<Integer, String>> it_checkNameMap = checkNameMap.entrySet().iterator();
        
        try {
   
          DocumentBuilderFactory docFactory = DocumentBuilderFactory.newInstance();
          DocumentBuilder docBuilder = docFactory.newDocumentBuilder();
   
          // root elements
          Document doc = docBuilder.newDocument();
          Element rootElement = doc.createElement("Company");
          doc.appendChild(rootElement);
          while (it_checkListMap.hasNext()){
              Map.Entry pairs_checkListMap = (Map.Entry)it_checkListMap.next();
              // staff elements
              Element checkList = doc.createElement("Checks");
              checkList.appendChild(doc.createTextNode(StringConverter<pairs_checkListMap.getValue()>));
              rootElement.appendChild(checkList);
              
              while(it_checkNameMap.hasNext()){
                  // firstname elements
                  Element CheckName = doc.createElement("Name");
                  CheckName.appendChild(doc.createTextNode((String) pairs_checkListMap.getValue()));
                  checkList.appendChild(CheckName);
              }

          }
          // write the content into xml file
          TransformerFactory transformerFactory = TransformerFactory.newInstance();
          Transformer transformer = transformerFactory.newTransformer();
          DOMSource source = new DOMSource(doc);
          StreamResult result = new StreamResult(file);
   
          transformer.transform(source, result);
   
          System.out.println("File saved!");
   
        } catch (ParserConfigurationException pce) {
            pce.printStackTrace();
        } catch (TransformerException tfe) {
            tfe.printStackTrace();
        }
    }
    
    
    public void getCheckedStandards(String file){
        TreeItem[] items = tree.getSelection();
        
        final Map<Integer, TreeItem> checkListMap;
        checkListMap = new HashMap<Integer, TreeItem>();
        
        final Map<Integer, String> checkNameMap;
        checkNameMap = new HashMap<Integer, String>();
        
        for (int i = 0; i < items.length; i++) {
            checkListMap.put(i, items[i]);
            //System.out.println("itemS: " + items[0]); 
            TreeItem[] child = items[i].getItems();
            for (int index=0; index < child.length; index++) { 
                if (child[index].getChecked()) {
                    System.out.println("item: " + index + ": " + child[index].getText()); 
                    checkNameMap.put(index, child[index].getText());
                }
            }
        }  
        write2XML(checkListMap, checkNameMap, file);
    }
    
}

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Tolgar

ASKER

I almost never choose average as the score but I didn't hear back from any expert after I responded their question to clarify my question.

mccarl

I almost never choose average as the score

Not a problem, it seems appropriate here as you seem to have found the solution on your own before I could return to your question. Also, just to let you know that since all the experts here contibute on a volunteer basis, sometimes it may take a number of days to reply. And, at least in my case, over the weekend it is less likely that I would be able to get back to you. I realise that that could be frustrating when all you want to do is to get a solution to your problem but that's just the nature of a system like this. Anyway, I am glad that you were able to work it out for yourself! :)