How to iterate HashMap using JSTL forEach loop

SugarCRM Customization says:

OOH that’s great !!! surely this code will help me a lot … thanks

KanyTheCoder says:

What if you use in the jsp file? How will the code be altered then and how does that work…..?

KanyTheCoder says:

What I meant was this:

What if you use jsp:useBean in the jsp file? How will the code be altered then and how does that work…..?

prasad says:

in first foreach loop u missed to items=”${cityList}” k

Gura says:

I attempted using your hashmap example. In the jsp

//JSP

Country: ${entry.key} – Capital: ${entry.value}

However this does not work.

Shammi says:

Thanks

Sudipta says:

Thanks man..your blogs helped me a lot..thank you once again..

Daniel says:

Thank you for this info! But you can actually get access to the value by just using the key, like if it was an array:

Pannaga says:

public class StmtController extends HttpServlet {
	@Override
	public void doPost(HttpServletRequest req, HttpServletResponse resp)
			throws ServletException, IOException {
		
		RequestDispatcher rd;
		HttpSession s=req.getSession();
		CustDTO cust=(CustDTO) s.getAttribute("cust");
		int accn=cust.getAccno();
		try {
			ArrayList a=new ArrayList();
			DesDAO d=new DesDAO();
			a=d.getStmt(accn);
			
			req.setAttribute("list", a);
			rd=req.getRequestDispatcher("stmt.jsp");
			rd.forward(req, resp);

		} catch (SQLException e) {
			resp.sendRedirect("error.html");	
		}
		
	}
}

This is my servlet.


package com.pannagaOrg.mvcBankApp.dto;

public class DesDTO {
	private String descr;
	private String dt;
	private int accno;
	public int getAccno() {
		return accno;
	}
	public void setAccno(int accno) {
		this.accno = accno;
	}
	public String getDescr() {
		return descr;
	}
	public void setDescr(String descr) {
		this.descr = descr;
	}
	public String getDt() {
		return dt;
	}
	public void setDt(String dt) {
		this.dt = dt;
	}
	
}
This is my DTO


package com.pannagaOrg.mvcBankApp.dao;

import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.ArrayList;

import com.pannagaOrg.mvcBankApp.dto.CustDTO;
import com.pannagaOrg.mvcBankApp.dto.DesDTO;
import com.pannagaOrg.mvcBankApp.utility.DBSingleton;

public class DesDAO {
	
	public ArrayList getStmt(int accn) throws SQLException
	{
		ArrayList desList=new ArrayList();
		String query="SELECT * FROM bank.trans WHERE accno=?";
		DBSingleton conObj=DBSingleton.getConnectionObject();
		Connection con=conObj.getCon();
		PreparedStatement pstmt=con.prepareStatement(query);

		pstmt.setInt(1,accn);
		ResultSet res = pstmt.executeQuery();
		
		while(res.next())
		{
			String des=res.getString(3);
			String dt = res.getString(4);
			DesDTO d=new DesDTO();
			d.setDescr(des);
			d.setDt(dt);
			desList.add(d);
		}
		return desList;
	}

}

This is my DAO

Insert title here

click here to see statement:

accn

description

date

Here is my jsp

But i am getting an exception
org.apache.jasper.JasperException: An exception occurred processing JSP page /stmt.jsp at line 19

16:
17:
18: accn
19:
20:
21:
22:

Stacktrace:
org.apache.jasper.servlet.JspServletWrapper.handleJspException(JspServletWrapper.java:510)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:401)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:313)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:260)
javax.servlet.http.HttpServlet.service(HttpServlet.java:717)

root cause

javax.servlet.ServletException: javax.servlet.jsp.JspTagException: Don’t know how to iterate over supplied “items” in <forEach>
org.apache.jasper.runtime.PageContextImpl.doHandlePageException(PageContextImpl.java:862)

Please help me

Dhande says:

Thanks…

satish says:

If that Map is present in one method like below.

@ModelAttribute("categoriesList")
	public Map populateCategoryList() {
		Map categoryMap = new LinkedHashMap();
		try {
			logger.debug("Call to programResourceService to get all the categoriesList ");
			List articleCategory = service.getCategory();
			logger.debug("got the category list of size::"+articleCategory.size());
			//categoryMap.put("0", "Select a Category");
			for (int i = 0; i < articleCategory.size(); i++) {
				CategoriesForm categoryForm = (CategoriesForm) articleCategory
						.get(i);
				logger.debug("Category Id and Name ::"+categoryForm.getCategoryId().toString() +" :: "+categoryForm.getCategoryName());
				categoryMap.put(categoryForm.getCategoryId().toString(),
						categoryForm.getCategoryName());
			}
			logger.debug("Contruced categories form list and the size is : "+articleCategory.size());
		} catch (Exception e) {
			logger.error("Error while getting the categories List",e);
		}
		return categoryMap;
	}

how to get the values key and value to a select box…?

Daya says:

Hi All,
can any one please help me out that are there any chances were in we can remove hash map key/value pair through JSTL

below is the piece of code,

${a.key}

now we have got the MAP key, can we remove this key from existing Map

Thanks
Daya

Deepak Kataria says:

Is it possible to iterate over arrays?

prasad says:

thank you,but my map value is Object type..could you please tell me how can i iterate my object values in jsp

Binh Thanh Nguyen says:

Thanks, nice tips

eek says:

Iterating through map is bugged. It iterates successfully if there is only 1 static map. However, if map changes dynamically, let’s say by selecting an item from dropdown menu, a new map is generated for iteration, then c:foreach tries to use the first map for iteration which results in incorrect data..

Pratik Gaurav says:

Nice Page