Passing array of Strings from JSP page to Server

Question

In my spring aplication, I am trying pass a array of strings from my view, through this code:

$( ".form" ).submit(function( event ) {
      event.preventDefault();
      var $form = $( this ), url = $form.attr( "action" );

      var selecao_permissoes=[];
        $('#selecao option').each(function(){
            selecao_permissoes.push($(this).val());
        });

      var nome = $("input[name=nome]").val();

      $.ajax({
          type: "POST",
          url: url,
          data: { nome: nome, permissoes: selecao_permissoes }
        }).done(function( msg ) {
            $("#"+msg).show();
            $(".form").each (function(){
                  this.reset();
            });
        });
});

To this method from my Service class:

public boolean cadastra(HttpServletRequest request, HttpServletResponse response) {
    String nome_grupo = request.getParameter("nome");
    String[] permissoes = request.getParameterValues("permissoes");

    if(nome_grupo == null || permissoes == null) {
        System.out.println("nome_grupo = "+nome_grupo);
        System.out.println("permissoes = "+permissoes);
        return false;
    }

    GrupoPermissao grupo = new GrupoPermissao();
    grupo.setNome(nome_grupo);

    List<Permissao> lista = new ArrayList<Permissao>();
    for(int i=0; i<permissoes.length; i++)
        lista.add(permissao.findById(Integer.valueOf(permissoes[i]).intValue()));
    grupo.setPermissao(lista);

    return grupo_permissao.persist(grupo);
}

The atribute 'nome' is receiving the correct value, but the atribute 'permissoes' is receiving a null value.

Anyone can tell me why this is happening? I can't figure out a motive for that.

Answer 1

Try with:

String[] permissoes = request.getParameterValues("permissoes[]");

I don't know why, it's just annoying and how jquery are doing if for some reason if your posting an array and want it in your java servlet.