How can I manage a multidimensional array with Struts Form

Question

I'm using Apache Struts 1.3 to render a grid, whitch is a html form embebed in a .jsp. Something like

<html:form action="/MyController.do?action=processForm">
<html:text property="taxation[0][0]" value="" styleClass="gridInputs"></html:text>
<html:text property="taxation[0][1]" value="" styleClass="gridInputs"></html:text>
 ...
<html:text property="taxation[10][10]" value="" styleClass="gridInputs"></html:text>

MyController is associated to an ActionForm:

public class MyForm extends ActionForm{

protected String taxation[][]= new String [10][10]; 

public String[] getTaxation() {
    return taxation;
}

public void setTaxation(String[][] taxation) {
    this.taxation = taxation;
}

The problem arise when I try to retrieve the information submitted by the form. Whithin MyController.class I've a simple dispatcher action

public class MyController extends DispatchAction {
public ActionForward processForm(ActionMapping mapping, ActionForm form,
        HttpServletRequest request, HttpServletResponse response) {

    MyForm myform = (MyForm) form;

            // Here i can use the getter method to retrieve an array, but
           // myform is already wrong populated from struts


    }


    return mapping.findForward("stage2");

}

I know I can use a Vector (unidimensional array) and It works just fine, but regrettably I need to follow some specs (and the specs force me to use the class MyForm with a 10x10 matrix...). How would be the right way to populated a two dimensional array using struts?

Thank you for the help!

Answer 1

Struts does not support filling of multidimensional array in Form bean. However, it does handle uni-dimensional array of an object. So as a work around if you can create a class (say MatrixRow) which itself contains an Uni-dimensional array and then you can create an Uni-dimensional array of that object in the form bean. Your new class will be look like

    public class MatrixRow {

    private String matrixCol[] = new String[10];

    /**
     * @return the matrixCol
     */
    public String[] getMatrixCol() {
        return matrixCol;
    }

    /**
     * @param matrixCol the matrixCol to set
     */
    public void setMatrixCol(String[] matrixCol) {
        this.matrixCol = matrixCol;
    }
}

Then in your form bean

private MatrixRow[] arrMatrix = new MatrixRow[10];
/**
     * @return the arrMatrix
     */
    public MatrixRow[] getArrMatrix() {
        return arrMatrix;
    }

    /**
     * @param arrMatrix the arrMatrix to set
     */
    public void setArrMatrix(MatrixRow[] arrMatrix) {
        this.arrMatrix = arrMatrix;
    }

and In your JSP, you can use it something like

    <html:form action="biArrayTestAction.do">
    <table cellpadding="0" cellspacing="0" width="100%">
    <logic:iterate id="matrixRows" name="biArrayTestForm" 
                   property="arrMatrix" indexId="sno" 
                   type="logic.MatrixRow" >
    <tr>
        <td><bean:write name="sno"/></td>
    <logic:iterate id="matrixCol" name="matrixRows" property="matrixCol" indexId = "colNo">
        <td>
           <input type="text" name="arrMatrix[<%=sno %>].matrixCol[<%=colNo %>]">
        </td>
    </logic:iterate>
    </tr>
    </logic:iterate>
    <tr>
      <td align="center" valign="top" colspan="2">
        &nbsp;
      </td>
    </tr>
    <tr>
        <td align="center" valign="top" colspan="2">
          <html:submit property="command" value="Test"></html:submit>
        </td>
    </tr>
   </table>

When you submit that form you will get all columns of MatrixRow object filled with the values.

I hope this will help you. I don't find any other way of using multidimensional array in Struts1.