JavaBean Servlet Jsp Pagination
I am trying to display data into multiple pages. I am not sure what I am doing wrong over here. Can someone let me know what I am doing wrong over here. I can get all the data in one page but cant get it into multiple pages. Thank you
I have Employee jsp page shown as below
<script>
function setPageName() {
document.EmployeeList.pageName.value="Employee";
document.EmployeelList.submit();
}
</script>
<BODY text="#000000" link="#0000FF" vlink="#800080" alink="#FF0000" onload="setPageName()">
<FORM NAME="EmployeeList" METHOD=POST ACTION="EmployeeServlet">
<INPUT TYPE=HIDDEN NAME="noRowsOnPage" VALUE="<%= empBean.getNoRowsOnPage()%>">
<INPUT TYPE=HIDDEN NAME="beginRowNumOnPage" VALUE="<%= empBean.getBeginRowNumOnPage()%>">
<INPUT TYPE=HIDDEN NAME="endRowNumOnPage" VALUE="<%= empBean.getEndRowNumOnPage()%>">
<%
Collection dtlItems = empBean.getDetailItems();
Iterator it = dtlItems.iterator();
int i = 0;
String colorStr = null;
while(it.hasNext()){
EmployeeItemBean empDtlItem = (EmployeeItemBean) it.next();
}
%>
<TR>
<TD ><%= auditemailDtlItem.getSeqNoHTML()%></TD>
<TD><%= auditemailDtlItem.getAuditorName()%> </TD>
<TD><%= auditemailDtlItem.getEmail()%></TD>
</TR>
<%
i++;
} %>
<TR>
<TD align="center">
<% if(empBean.getBeginRowNumOnPage() == 1 || empBean.getBeginRowNumOnPage() == 0) {%>
<INPUT TYPE=SUBMIT NAME="action" VALUE="First" disabled>
<INPUT TYPE=SUBMIT NAME="action" VALUE="Prev" disabled>
<%} else {%>
<INPUT TYPE=SUBMIT NAME="action" VALUE="First">
<INPUT TYPE=SUBMIT NAME="action" VALUE="Prev">
<%} %>
<% if(empBean.getEndRowNumOnPage() == empBean.getTotalRowCount()) {%>
<INPUT TYPE=SUBMIT NAME="action" VALUE="Next" disabled>
<INPUT TYPE=SUBMIT NAME="action" VALUE="Last" disabled>
<%} else {%>
<INPUT TYPE=SUBMIT NAME="action" VALUE="Next">
<INPUT TYPE=SUBMIT NAME="action" VALUE="Last">
<%} %>
</TD>
</TR>
</TABLE>
My servlet looks like this:
public class EmployeeServlet {
public void defaultAction(HttpServletRequest request,HttpServletResponse response)
throws ServletException, IOException
{
EmployeeWebBean ewBean = new EmployeeWebBean();
ewBean.initializePage();
ewBean.retrieveSessionData(request);
ewBean.retrieveSubmitData(request, response);
ewBean.determineAction();
ewBean.processActions();
ewBean.populateModelBean();
ewBean.dispatchToJSP(this, request,response);
return;
}
}
My employeeWebBean looks like this where all processing takes place:
private final static int ACTION_INITIAL_LOAD = 0;
private final static int ACTION_GO = 1;
private final static int ACTION_PREV = 2;
private final static int ACTION_NEXT = 3;
private final static int ACTION_FIRST = 4;
private final static int ACTION_LAST = 5;
private final static int PREV = 0;
private final static int NEXT = 1;
private final static int FIRST = 2;
private final static int LAST = 3;
public void initializePage()
{
_empBean = new EmployeeBean();
_actionPick = ACTION_INITIAL_LOAD;
_clkAction = new String();
_beginRowNumOnPage = 0;
_endRowNumOnPage = 0;
}
public void determineAction()
{
if(_clkAction != null){
if(_clkAction.indexOf("Go") != -1)
_actionPick = ACTION_GO;
else if (_clkAction.indexOf("Next") != -1)
_actionPick = ACTION_NEXT;
else if (_clkAction.indexOf("Prev") != -1)
_actionPick = ACTION_PREV;
else if (_clkAction.indexOf("First") != -1)
_actionPick = ACTION_FIRST;
else if (_clkAction.indexOf("Last") != -1)
_actionPick = ACTION_LAST;
else
_actionPick = ACTION_INITIAL_LOAD;
}
}
public void retrieveSessionData(HttpServletRequest request)
{
HttpSession session = request.getSession();
if (session.getAttribute("pageName") != null)
_sessPageName = (String) session.getAttribute("pageName");
_empBean.setPageName(_sessPageName);
}
public void retrieveSubmitData(HttpServletRequest request,HttpServletResponse response)
{
_clkAction = request.getParameter("action");
String _tempString = new String();
_tempString = request.getParameter("actionLink");
this.determineAction();
_tempString = request.getParameter("noRowsOnPage");
if (_tempString != null)
_noRowsOnPage = Integer.valueOf(_tempString).intValue();
else
_noRowsOnPage = 0;
_tempString = request.getParameter("beginRowNumOnPage");
if (_tempString != null)
_beginRowNumOnPage = Integer.valueOf(_tempString).intValue();
else
_beginRowNumOnPage = 0;
_tempString = request.getParameter("endRowNumOnPage");
if (_tempString != null)
_endRowNumOnPage = Integer.valueOf(_tempString).intValue();
else
_endRowNumOnPage = 0;
_pageName = request.getParameter("pageName");
if (_actionPick == ACTION_GO || _actionPick == ACTION_PREV || _actionPick == ACTION_NEXT || _actionPick == ACTION_FIRST
|| _actionPick == ACTION_LAST)
{
_hdTxnType = request.getParameter("hdTxnType");
_cbEmployee = request.getParameter("cbEmployee");
_cbSort = request.getParameter("cbSort");
_tbSearchVar = request.getParameter("tbSearchVar").trim();
}
if (_actionPick == ACTION_INITIAL_LOAD) {
_cbEmployee = new String("1");
_cbSort = new String("1");
}
}
public void populateModelBean()
{
_empBean.setTxnType(_hdTxnType);
_empBean.setSelectedEmployee(_cbEmployee);
_empBean.setSearchVar(_tbSearchVar);
_empBean.setSelectedSort(_cbSort);
_empBean.setActionPick(_actionPick);
_empBean.setPageName(_sessPageName);
}
public boolean initialPage()
{
if(_actionPick == ACTION_INITIAL_LOAD)
return true;
else
return false;
}
public void dispatchToJSP(EmployeeServlet employeeServlet, HttpServletRequest request,HttpServletResponse response)
throws ServletException, IOException
{
response.setContentType("text/html");
RequestDispatcher dispatcher = null;
// Put the object into request object to pass to JSP
request.setAttribute("empBean", _empBean);
if (_pageName == null || _pageName.trim().length() == 0 || _pageName.equals("Employee")){
dispatcher = employeeServlet.getServletContext().getRequestDispatcher("/EmployeeList.jsp");
}
dispatcher.include(request, response);
}
public void processActions()
{
switch(_actionPick)
{
case ACTION_INITIAL_LOAD:
_empBean.getList(FIRST, 0, 0, _pageName,
_userProfile.getUserId().trim());
case ACTION_GO:
_empBean.setSearchVar(_tbSearchVar);
_empBean.setSelectedEmployee(_cbEmployee);
_empBean.setSelectedSort(_cbSort);
_empBean.clearAllDtlItem();
_empBean.getList(FIRST, 0, 0, _pageName,
_userProfile.getUserId().trim());
break;
case ACTION_PREV:
_empBean.setSearchVar(_tbSearchVar);
_empBean.setSelectedEmployee(_cbEmployee);
_empBean.setSelectedSort(_cbSort);
_empBean.clearAllDtlItem();
_empBean.getList(PREV, _beginRowNumOnPage,
_endRowNumOnPage, _pageName, _userProfile.getUserId().trim());
break;
case ACTION_NEXT:
_empBean.setSearchVar(_tbSearchVar);
_empBean.setSelectedEmployee(_cbEmployee);
_empBean.setSelectedSort(_cbSort);
_empBean.clearAllDtlItem();
_empBean.getList(NEXT, _beginRowNumOnPage,
_endRowNumOnPage, _pageName, _userProfile.getUserId().trim());
break;
case ACTION_FIRST:
_empBean.setSearchVar(_tbSearchVar);
_empBean.setSelectedEmployee(_cbEmployee);
_empBean.setSelectedSort(_cbSort);
_empBean.clearAllDtlItem();
_empBean.getList(FIRST, _beginRowNumOnPage,
_endRowNumOnPage, _pageName, _userProfile.getUserId().trim());
break;
case ACTION_LAST:
_empBean.setSearchVar(_tbSearchVar);
_empBean.setSelectedEmployee(_cbEmployee);
_empBean.setSelectedSort(_cbSort);
_empBean.clearAllDtlItem();
_empBean.getList(LAST, _beginRowNumOnPage,
_endRowNumOnPage, _pageName, _userProfile.getUserId().trim());
break;
default:
break;
}
I have EmployeeBean where I get all the data
public java.util.Vector getList(int mode, int firstRow, int lastRow, String pageName, String userID) {
java.util.Vector myEmployeeList = new java.util.Vector();
StringBuffer sql = new StringBuffer();
DbUtil db = null;
ResultSet rset = null;
int rowsToBeFeched = MAX_NUM_ROWS_IN_PAGE;
int preserveFirstRow = 0;
int preserveLastRow = 0;
try
{
db = new DbUtil();
sql.append("SELECT id_no, name, email ");
if ((this.getSelectedColumn() != null)&& (this.getSelectedColumn().equals("1"))){
sql.append(" from employee ");
}
if ((this.getSelectedColumn() != null)&& (this.getSelectedColumn().equals("2"))){
sql.append(" from employee ");
sql.append(" where id_no = '");
sql.append(this.getSearchVar());
sql.append("'");
}
if (this.getSelectedSort() != null) {
if(this.getSelectedSort().equals("1"))
sql.append(" ORDER BY id_no");
else if(this.getSelectedSort().equals("2"))
sql.append(" ORDER BY name");
else
sql.append(" ORDER BY id_no");
} else
sql.append(" ORDER BY id_no");
rset = db.executeQuery(sql.toString(),true);
rset.last();
int _totalRows = rset.getRow();
this.setTotalRowCount(_totalRows);
rowsToBeFeched = MAX_NUM_ROWS_IN_PAGE;
if (firstRow < rowsToBeFeched) {
preserveFirstRow = 0;
} else {
preserveFirstRow = firstRow - rowsToBeFeched;
}
if (lastRow < 2 * rowsToBeFeched) {
preserveLastRow = rowsToBeFeched;
} else {
preserveLastRow = lastRow - rowsToBeFeched;
}
rowsToBeFeched = _totalRows;
rset.beforeFirst();
if (mode == FIRST) {
this.setBeginRowNumOnPage(1);
} else if (mode == LAST) {
if (_totalRows <= rowsToBeFeched)
this.setBeginRowNumOnPage(1);
else {
rset.last();
rset.relative(0 - rowsToBeFeched);
this.setBeginRowNumOnPage(rset.getRow() + 1);
}
} else if (mode == NEXT) {
if (_totalRows <= rowsToBeFeched)
this.setBeginRowNumOnPage(1);
else {
rset.absolute(lastRow);
this.setBeginRowNumOnPage(rset.getRow() + 1);
}
} else if (mode == PREV) {
if (firstRow <= (rowsToBeFeched + 1)) {
this.setBeginRowNumOnPage(1);
rset.beforeFirst();
} else {
rset.absolute(firstRow - rowsToBeFeched - 1);
this.setBeginRowNumOnPage(rset.getRow() + 1);
开发者_JAVA百科 }
}
clearAllDtlItem();
if (rset != null) {
int i = 0;
while(rset.next() && i < rowsToBeFeched) {
EmployeeBean myEmployee = new EmployeeBean();
myEmployee.setIdNo(rset.getString(1).trim());
myEmployee.setName(rset.getString(2));
myEmployee.setEmail(rset.getString(3));
myEmployeeList.addElement(myEmployee);
}
Enumeration e = myEmployeeList.elements();
while (e.hasMoreElements()) {
EmployeeBean nextEmployee = (EmployeeBean) e.nextElement();
this.addDtlItem(nextEmployee.getIdNo(), nextEmployee.getName(), nextEmployee.getEmail());
}
i++;
}
setEndRowNumOnPage(getBeginRowNumOnPage() + getNbrDtlItems() - 1);
if (preserveFirstRow == 0) {
mode = FIRST;
} else {
mode = NEXT;
}
getList( mode, preserveFirstRow, preserveLastRow, "Employee", userID);
}
public void addDtlItem(String idNo, String name, String email )
{
EmployeeItemBean detailItem = new EmployeeItemBean(idNo, name, email );
_dtlListArray.add(detailItem);
}
Consider using Java Based Display Tag library.
It makes setting up tables, pagination and sorting really easy.
You can learn more about it here http://www.displaytag.org/1.2/
加载中,请稍侯......
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