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javaspringjsphashmapjstl

How to iterate over a list of objects which have a map as a field in jstl?


I have a class Spravochnik which has a field HashMap. How to iterate over it with jstl? I want to a jsp page to show me table. The Spravochnik map maps column name to column object of a given table (column count can be different depending on the table). This is my method in controller.


 @RequestMapping(value = "/list")
  public String getSpravochniks(Model m, @RequestParam String tableName)
  {
    List<Spravochnik> spravList =
        spravochnikService.findAll(tableName);
    m.addAttribute("spravList", spravList);
    return "list";
  }

when i have my jsp like below it shows error Attribute qualified name must be unique within an element (id is a field of superclass Spravochnik inherits


  <c:forEach var="sprav" items="${spravList}">
            <tr>
                <td>
                    ${sprav.id}
                </td>
                <td>
                    ${sprav.map}
                </td>
            </tr>
        </c:forEach>

Spravochnik.class

public class Spravochnik extends BaseEntity {

    private HashMap<String, Object> map;

    public HashMap<String, Object> getMap() {
        return map;
    }

    public void setMap(HashMap<String, Object> map) {
        this.map = map;
    }  

}

Also maybe SpravochnikRowMapper

public class SpravochnikRowMapper implements RowMapper<Spravochnik> {
    @Override
    public Spravochnik mapRow(ResultSet rs, int arg1) throws SQLException {
        Spravochnik spr = new Spravochnik();
        ResultSetMetaData rsmeta = rs.getMetaData();
        HashMap<String, Object> map = new HashMap<>();
        int columnCount = rsmeta.getColumnCount();

        for(int column = 1; column <= columnCount; column++){
            map.put(rsmeta.getColumnName(column),rs.getObject(column));
        }

        return spr;
    }
}

Solution

  • I think you have to iterate map (the field map of the class Spravochnik) too. Maybe like that:

     <c:forEach var="sprav" items="${spravList}">
            <tr>
                <td>
                    ${sprav.id}
                </td>
                <td>
                    <c:forEach items="${sprav.map}" var="entry">
                      Key = ${entry.key}, value = ${entry.value}<br>
                    </c:forEach> 
                </td>
            </tr>
        </c:forEach>