Solved

Exporting Query Results as XML

Posted on 2006-10-19
6
222 Views
Last Modified: 2010-03-31
Hi experts,

Maybe there is a better way than what i'm doing.  

Im using mySQL and Hibernate...

I want to convert database info to XML, but i think the http://www.hibernate.org/186.html won't give me what i want.


I have a tree of data which I manually inputted in my database.
the roots have REF=0, and each subcategory has the REF of its parent.

id     category_name     REF
---------------------------
1      category1                 0
2      category2                 0
3      category1.1              1
4      category1.2              1
5      category2.1              2
...

I need to format this tree to XML.  So i'm trying to think of a good algorithm.

I figure I'll start by downloading the whole table

Then

public String getTreeInXML(ArrayList categories) {
   
   TreeMap root = new TreeMap();
   Iterator itr = categories.iterator();
   
   while (itr.hasNext()) {
      Category cat = (Category)itr.next();
      if (cat.getRef().intValue() == 0)
         root.put(cat.getRef(), );
      else
         ...        
   }

um, ok, so i will come back to this.  be back to work on it later...
}
0
Comment
Question by:dbrownell83
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
  • 3
6 Comments
 
LVL 14

Expert Comment

by:hoomanv
ID: 17767960
0
 
LVL 1

Author Comment

by:dbrownell83
ID: 17770967
i need algorithmic help more than simple pojo conversion.

this is the latest code... still thinking about it.  there has GOT to be a better way


      // Daniel Brownell 2006
      public String getTreeInXML(ArrayList categories) {
               
               Hashtable allCategories = new Hashtable();
               Hashtable rootTable = new Hashtable();
               
               while (categories.size() != 0) {
                    
                     Iterator itr = categories.iterator();
                    
                     while (itr.hasNext()) {
                        Subjectcategory cat = (Subjectcategory)itr.next();
                        allCategories.put(cat.getSubjectCategoryId(), cat);
                        
                  // if they are the main categories
                        if (cat.getRefSubjectHeader().intValue() == 0){
                           Hashtable subTable = new Hashtable();
                           subTable.put(cat.getSubjectCategoryId(), cat);
                           rootTable.put(cat.getSubjectCategoryId(), subTable);
                        }
                  
                  // otherwise, they are subcategoriez
                        else {
                               Hashtable parentReference = (Hashtable)rootTable.get(cat.getRefSubjectHeader());
                             //if parentRef is null, we need to put it in the allCategory List
                               if (parentReference != null) {

                                     Hashtable childReference = new Hashtable();
                                     childReference.put(cat.getSubjectCategoryId(), cat);
                                     rootTable.put(cat.getSubjectCategoryId(),childReference);
                                     
                               }
                              
                               else {
                              
                                     parentReference = (Hashtable) allCategories.get(cat.getRefSubjectHeader());
                                     
                                     if (parentReference == null) {
                                           allCategories.put(cat.getSubjectCategoryId(), cat);
                                           //it just hasnt got there yet.
                                           continue;
                                     }
                                     else {
                                           Hashtable childReference = new Hashtable();
                                           childReference.put(cat.getSubjectCategoryId(), cat);
                                           parentReference.put(cat.getSubjectCategoryId(),childReference);
                                     }
                                            
                               }
                                
                        }
                        
                        categories.remove(cat);
                     }
               }
               
  //at this point, the bottom up way of saving the data
  // has been turned upside down, so that a rootTable
  // can call .values(), and have the children,
  // and iterate through those values as long as there are child trees to do so
               
               
               
      }
0
 
LVL 1

Author Comment

by:dbrownell83
ID: 17771280
OK,

so there was a better way
i used recursion and MYSQL select statements.

try {
                
      SubjectcategoryDAO dao = new SubjectcategoryDAO ();
                
      Subjectcategory root = (Subjectcategory)dao.findByProperty("subjectCategoryId", 78).get(0);
      System.out.println(root);
                xml = new StringBuffer();
      xml = dao.getTreeInXML(xml, root);
             System.out.println(xml);
}
    catch (Exception e) {
          e.printStackTrace();
    }




      public StringBuffer getTreeInXML(StringBuffer xml, Subjectcategory cat)
       throws Exception {
            List list = findByProperty("refSubjectHeader", cat.getSubjectCategoryId());
            //
            Iterator itr = list.iterator();
            while (itr.hasNext()) {
                  Subjectcategory child = (Subjectcategory)itr.next();
                  xml = xml.append("<").append(child.getSubjectCategoryName()).append(">");
                  xml = getTreeInXML(xml, child);
                  xml = xml.append("</").append(child.getSubjectCategoryName()).append(">");
            }
            return xml;
          
      }  
      
0
 
LVL 1

Author Comment

by:dbrownell83
ID: 17771285
ok, since i answered my own question,
can someone tell me if the first way could have worked?  
0
 
LVL 1

Accepted Solution

by:
DarthMod earned 0 total points
ID: 17813882
Closed, 500 points refunded.
DarthMod
Community Support Moderator
0

Featured Post

Transaction Monitoring Vs. Real User Monitoring

Synthetic Transaction Monitoring Vs. Real User Monitoring: When To Use Each Approach? In this article, we will discuss two major monitoring approaches: Synthetic Transaction and Real User Monitoring.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Java had always been an easily readable and understandable language.  Some relatively recent changes in the language seem to be changing this pretty fast, and anyone that had not seen any Java code for the last 5 years will possibly have issues undeā€¦
In this post we will learn how to connect and configure Android Device (Smartphone etc.) with Android Studio. After that we will run a simple Hello World Program.
Viewers will learn one way to get user input in Java. Introduce the Scanner object: Declare the variable that stores the user input: An example prompting the user for input: Methods you need to invoke in order to properly get  user input:
This tutorial covers a practical example of lazy loading technique and early loading technique in a Singleton Design Pattern.

691 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question