title: JSP enctype="multipart/form-data" get null data
body: <p>When I use enctype=“multipart/form-data” for upload and input many data get null, if delete enctype=“multipart/form-data” it can get data but upload null. My code html   </p>
  
  <pre><code>&lt;form action="createvendor" method="post" enctype="multipart/form-data"&gt;
      &lt;div&gt;
          &lt;label&gt; &lt;input placeholder="Username:" type="text"
                         name="username" tabindex="1" &gt;
          &lt;/label&gt;
      &lt;/div&gt;
      &lt;div&gt;
          &lt;label&gt; &lt;input placeholder="Password" type="password"
                         name="password" tabindex="2" &gt;
          &lt;/label&gt;
      &lt;/div&gt;
      &lt;div&gt;
          &lt;label&gt; &lt;input placeholder="Firstname:" type="text"
                         name="firstname" tabindex="3" &gt;
          &lt;/label&gt;
      &lt;/div&gt;
      &lt;div&gt;
          &lt;label&gt; &lt;input placeholder="Lastname:" type="text"
                         name="lastname" tabindex="4" &gt;
          &lt;/label&gt;
      &lt;/div&gt;
      &lt;div&gt;
          &lt;label&gt; &lt;input placeholder="ID card:" type="text"
                         name="personalID" tabindex="5" maxlength="13"
                         onKeyUp="if(isNaN(this.value)){ alert('กรุณากรอกตัวเลข 13 หลักเท่านั้น'); this.value='';}"
                  &gt;
          &lt;/label&gt;
      &lt;/div&gt;
      &lt;div class="registration_form"&gt;
          &lt;div style="position: relative;"&gt;
              &lt;a class='btn btn-primary'&gt; Choose your ID card picture &lt;input
                      required class="form-control" type="file"
                      style='position: absolute; z-index: 2; top: 0; left: 0; filter: alpha(opacity = 0); -ms-filter: "progid:DXImageTransform.Microsoft.Alpha(Opacity=0)"; opacity: 0; background-color: transparent; color: transparent;'
                      name="picturePersonalID"
                      onchange='$("#upload-file-info").html($(this).val());'&gt;
              &lt;/a&gt;&amp;nbsp; &lt;span class='label label-info' id="upload-file-info"&gt;&lt;/span&gt;
          &lt;/div&gt;
      &lt;/div&gt;
  &lt;/form&gt;
  </code></pre>
  
  <p>I want to upload and input many data and send data to servlet.</p>