Swing/HtmlTableTransferHandler の変更点

---
category: swing
folder: HtmlTableTransferHandler
title: JTableのHTML形式コピーをカスタマイズする
tags: [JTable, TransferHandler, Html, JColorChooser]
author: aterai
pubdate: 2014-09-01T00:14:35+09:00
description: JTableのセルを選択してクリップボードにHTMLテキストをコピーするとき、そのセルのクラスに応じて生成するタグを変更します。
image: https://lh5.googleusercontent.com/-VsQ_pmP_GKM/VAM3IR6IvyI/AAAAAAAACMI/97dngpaAQn8/s800/HtmlTableTransferHandler.png
---
* Summary [#summary]
`JTable`のセルを選択してクリップボードに`HTML`テキストをコピーするとき、そのセルのクラスに応じて生成するタグを変更します。

#download(https://lh5.googleusercontent.com/-VsQ_pmP_GKM/VAM3IR6IvyI/AAAAAAAACMI/97dngpaAQn8/s800/HtmlTableTransferHandler.png)

* Source Code Examples [#sourcecode]
#code(link){{
class HtmlTableTransferHandler extends TransferHandler {
  // @see javax/swing/plaf/basic/
  //      BasicTableUI.TableTransferHandler#createTransferable(JComponent)
  @Override protected Transferable createTransferable(JComponent c) {
    if (c instanceof JTable) {
      JTable table = (JTable) c;
      int[] rows;
      int[] cols;

      if (!table.getRowSelectionAllowed() && !table.getColumnSelectionAllowed()) {
        return null;
      }

      if (table.getRowSelectionAllowed()) {
        rows = table.getSelectedRows();
      } else {
        int rowCount = table.getRowCount();

        rows = new int[rowCount];
        for (int counter = 0; counter < rowCount; counter++) {
          rows[counter] = counter;
        }
      }

      if (table.getColumnSelectionAllowed()) {
        cols = table.getSelectedColumns();
      } else {
        int colCount = table.getColumnCount();
        cols = new int[colCount];
        for (int counter = 0; counter < colCount; counter++) {
          cols[counter] = counter;
        }
      }

      if (cols == null || rows.length == 0 || cols.length == 0) {
        return null;
      }

      StringBuffer plainBuf = new StringBuffer();
      StringBuffer htmlBuf = new StringBuffer(64);

      htmlBuf.append("<html>\n<body>\n<table border='1'>\n");

      for (int row = 0; row < rows.length; row++) {
        htmlBuf.append("<tr>\n");
        for (int col = 0; col < cols.length; col++) {
          Object obj = table.getValueAt(rows[row], cols[col]);
          String val = Objects.toString(obj, "") + "\t";
            // .replace("&", "&amp;").replace("<", "&lt;").replace(">", "&gt;");
          plainBuf.append(val);

          if (obj instanceof Date) {
            String v = Objects.toString((Date) obj, "");
            htmlBuf.append("  <td><time>" + v + "</time></td>\n");
          } else  if (obj instanceof Color) {
            htmlBuf.append(String.format(
                "  <td style='background-color:#%06X'>&nbsp;</td>%n",
                ((Color) obj).getRGB() & 0xFF_FF_FF));
          } else {
            htmlBuf.append("  <td>" + Objects.toString(obj, "") + "</td>\n");
          }
        }
        // we want a newline at the end of each line and not a tab
        plainBuf.deleteCharAt(plainBuf.length() - 1).append("\n");
        htmlBuf.append("</tr>\n");
      }

      // remove the last newline
      plainBuf.deleteCharAt(plainBuf.length() - 1);
      htmlBuf.append("</table>\n</body>\n</html>");

      return new BasicTransferable(plainBuf.toString(), htmlBuf.toString());
    }

    return null;
  }

  @Override public int getSourceActions(JComponent c) {
    return TransferHandler.COPY;
  }
}
}}

* Description [#explanation]
* Description [#description]
- 上`JTable`:
-- デフォルトの`BasicTableUI.TableTransferHandler`を使用
- 下`JTable`:
-- `HtmlTableTransferHandler`を設定
-- `TransferHandler#createTransferable(JComponent)`をオーバーライドしてクリップボードに転送する`text/html`なテキストを独自に作成
--- `text/plain`は`BasicTableUI.TableTransferHandler`のコピーをそのまま使用
--- `<table>`タグに属性`border='1'`を追加
-- セルのクラスに応じたタグを生成
--- `Date`: `<time>...</time>`で囲む
--- `Color`: `<td>`に`style='background-color:#%06x'>`で背景色を設定

* Reference [#reference]
- [https://www.ne.jp/asahi/hishidama/home/tech/java/swing/TransferHandler.html Java Swing「ドラッグ&ドロップ」メモ(Hishidama's Swing-TransferHandler Memo)]
- [[JTableでプロパティ一覧表を作成する>Swing/PropertyTable]]

* Comment [#comment]
#comment
#comment