code: protected GridBagConstraints createConstraints() {
          GridBagConstraints answer = new GridBagConstraints();
          answer.anchor = getAnchor();
          if (colspan < 1) {
              colspan = 1;
          }
          if (rowspan < 1) {
              rowspan = 1;
          }
          if (isColfill())  {
              answer.fill = isRowfill()
                  ? GridBagConstraints.BOTH 
                  : GridBagConstraints.HORIZONTAL;
          }
          else {
              answer.fill = isRowfill()
                  ? GridBagConstraints.VERTICAL 
                  : GridBagConstraints.NONE;
          }
          answer.weightx = 0.2;
          answer.weighty = 0;
          answer.gridwidth = colspan;
          answer.gridheight = rowspan;
          return answer;
      }
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