在Sun的官方網站上對Editor和Renderer的解釋是如下：
Renderer：
Instead, a single cell renderer is generally used to draw all of the cells that contain the same type of data. You can think of the renderer as a configurable ink stamp that the table uses to stamp apPRopriately formatted data onto each cell. When the user starts to edit a cell's data, a cell editor takes over the cell, controlling the cell's editing behavior.
個人理解就是對于不同的數據顯示不同的格式，相當于在MVC中根據不同的Model選擇不同的View，Renderer就是給你這個選擇的權利。默認的幾種數據的顯示方式如下：

Double, Float — same as Number, but the object-to-text translation is performed by a NumberFormat instance (using the default number format for the current locale).

Date — rendered by a label, with the object-to-text translation performed by a DateFormat instance (using a short style for the date and time).

假如你有非凡的數據，想有非凡的顯示方式，可以自己設定Cell的Renderer如下：
TableCellRenderer weirdRenderer = new WeirdRenderer();
table = new JTable(...) {
    public TableCellRenderer getCellRenderer(int row, int column) {
        if ((row == 0) && (column == 0)) {
            return weirdRenderer;
        }
        // else...
        return super.getCellRenderer(row, column);
    }
};
Editor是用于編輯數據，但是Renderer是用于顯示數據。
關于Editor，和Renderer遵守相同的法則