cofactor
asked on
java data structure
I have a issue with data structure. Please find the file attached . I have explained in detail. This involves JDBC and JSP.
display.doc
display.doc
This link gives some methods how to modfy query:
http://stackoverflow.com/questions/194852/concatenate-many-rows-into-a-single-text-string
What type of database do you have - is it Oracle or MySql, or something else?
If you want to do it on JSP side, perhpas you can post your jsp code
This is one more example how to do it using Oracle query;
these queries do not look very simple, but they work
http://stackoverflow.com/questions/468990/how-can-i-combine-multiple-rows-into-a-comma-delimited-list-in-oracle
ASKER
>>>If you want to do it on JSP side, perhpas you can post your jsp code
jsp is simple.
Made a VO list and iterator to display in table. I have posted the java code in the attachment . Please check that. I prefer java side solution.
jsp is simple.
Made a VO list and iterator to display in table. I have posted the java code in the attachment . Please check that. I prefer java side solution.
Try this query - if you have Oracle 9 it will work for you
I called table tstconcat - just change table name and it will work:
select userid, max(username) username,
substr(replace(replace
(xmlagg(xmlelement("x",responsibility) order by responsibility),'</x>'),'<x>',','),2) responsibility, max(email) email
from tstconcat
group by userid;
I didn't see any code other than retrieval from the database in the doc file
If you replace the query by the one abocve this same JDBC code should get you exactly
what you want
If you replace the query by the one abocve this same JDBC code should get you exactly
what you want
For a Java-only solution, give your VO a List of responsibilities and use a Map:
Map<String, UserVO> vos = new HashMap<String, UserVo>();
while (rs.next()) {
String userId = rs.getString("userid");
String username = rs.getString("username");
String responsibility = rs.getString("responsibility");
String email = rs.getString("email");
UserVO uvo = vos.get(userId);
if (uvo == null) {
uvo = new UserVO();
uvo.setUserId(userId);
uvo.setUsername(username);
uvo.setEmail(email);
uvo.getResponsibilties().add(responsibility);
}
else {
uvo.getResponsibilties().add(responsibility);
}
}
..............
class UserVo {
private List<String> responsibilities = new ArrayList<String>();
...........
}
Sorry - don't forget to call put
uvo.setUserId(userId);
vos.put(userId, uvo);
This is the full code to do it in Java, but with query
change it is much easier
import java.sql.ResultSet;
import java.util.ArrayList;
import java.util.HashMap;
public class UserResponsibilities {
public UserResponsibilities(){
try{
ResultSet rs = null;
HashMap h = new HashMap();
HashMap n = new HashMap();
HashMap e = new HashMap();
ArrayList userids = new ArrayList();
while (rs.next()) {
String userId = rs.getString("userid");
String username = rs.getString("username");
String responsibility = rs.getString("responsibility");
String email = rs.getString("email");
n.put(userId, username);
e.put(userId, email);
if(!userids.contains(userId)) userids.add(userId);
if(h.get(userId) != null){
ArrayList al = (ArrayList)h.get(userId);
al.add(responsibility);
h.put(userId, al);
} else
{
ArrayList al = new ArrayList();
al.add(responsibility);
h.put(userId, al);
}
//populate in a VO and make a list of VO's and display in JSP
}
for(int jj=0; jj<userids.size(); jj++){
String userid = (String) userids.get(jj);
String username = (String) n.get(userid);
String email = (String)e.get(userid);
ArrayList al = (ArrayList) h.get(userid);
String resp = "";
for(int j=0; j<al.size(); j++){
resp += (String)al.get(j) + ",";
}
resp = resp.substring(0,resp.size()-1);
System.out.println(userid + " " + username + " " + resp + " " + email );
}
}catch(Exception ex){
}
}
}
ASKER
>>>Sorry - don't forget to call put
where you plan to call put ?
Could you please post the complete code once again ?
where you plan to call put ?
Could you please post the complete code once again ?
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ASKER
Excellent.
ASKER
Excellent
:)
There are two ways to do it - one is to modify SQL query, so
that it conactenates responsibilityes for the same users - that requires a little bit of
work with query but probably will not need any changes in JSP.
Another variant is to conactente these responsibilties in Java code
generating JSP. Which variant do you prefer?