关于JTable的打印讨论

Java中用Table显示数据是再正常不过的了，有各种各样的Table，有些表头是固定的，有些表头是随查询的条件不同而结果不同，另一些表头部分固定，部分随查询的条件不同而结果不同。

这些是在界面上的显示，但是如果要打印出来呢？

下面就以打印为住，讨论几种实现方式：

1、JTable的print(),这是直接调用JTable的打印方法，打印是直接将界面的样式打印出去的，例如这个Demo：

import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
import java.awt.print.*;
import java.text.*;

public class TablePrint {
  public static void main(String args[]) {
    final Object rows[][] = {
      {"one",   "ichi - \u4E00"},
      {"two",   "ni - \u4E8C"},
      {"three", "san - \u4E09"},
      {"four",  "shi - \u56DB"},
      {"five",  "go - \u4E94"},
      {"six",   "roku - \u516D"},
      {"seven", "shichi - \u4E03"},
      {"eight", "hachi - \u516B"},
      {"nine",  "kyu - \u4E5D"},
      {"ten",   "ju - \u5341"},
      {"one",   "ichi - \u4E00"},
      {"two",   "ni - \u4E8C"},
      {"three", "san - \u4E09"},
      {"four",  "shi - \u56DB"},
      {"five",  "go - \u4E94"},
      {"six",   "roku - \u516D"},
      {"seven", "shichi - \u4E03"},
      {"eight", "hachi - \u516B"},
      {"nine",  "kyu - \u4E5D"},
      {"ten",   "ju - \u5341"},
      {"one",   "ichi - \u4E00"},
      {"two",   "ni - \u4E8C"},
      {"three", "san - \u4E09"},
      {"four",  "shi - \u56DB"},
      {"five",  "go - \u4E94"},
      {"six",   "roku - \u516D"},
      {"seven", "shichi - \u4E03"},
      {"eight", "hachi - \u516B"},
      {"nine",  "kyu - \u4E5D"},
      {"ten",   "ju - \u5341"},
      {"one",   "ichi - \u4E00"},
      {"two",   "ni - \u4E8C"},
      {"three", "san - \u4E09"},
      {"four",  "shi - \u56DB"},
      {"five",  "go - \u4E94"},
      {"six",   "roku - \u516D"},
      {"seven", "shichi - \u4E03"},
      {"eight", "hachi - \u516B"},
      {"nine",  "kyu - \u4E5D"},
      {"ten",   "ju - \u5341"},
      {"one",   "ichi - \u4E00"},
      {"two",   "ni - \u4E8C"},
      {"three", "san - \u4E09"},
      {"four",  "shi - \u56DB"},
      {"five",  "go - \u4E94"},
      {"six",   "roku - \u516D"},
      {"seven", "shichi - \u4E03"},
      {"eight", "hachi - \u516B"},
      {"nine",  "kyu - \u4E5D"},
      {"ten",   "ju - \u5341"},
      {"one",   "ichi - \u4E00"},
      {"two",   "ni - \u4E8C"},
      {"three", "san - \u4E09"},
      {"four",  "shi - \u56DB"},
      {"five",  "go - \u4E94"},
      {"six",   "roku - \u516D"},
      {"seven", "shichi - \u4E03"},
      {"eight", "hachi - \u516B"},
      {"nine",  "kyu - \u4E5D"},
      {"ten",   "ju - \u5341"},
      {"one",   "ichi - \u4E00"},
      {"two",   "ni - \u4E8C"},
      {"three", "san - \u4E09"},
      {"four",  "shi - \u56DB"},
      {"five",  "go - \u4E94"},
      {"six",   "roku - \u516D"},
      {"seven", "shichi - \u4E03"},
      {"eight", "hachi - \u516B"},
      {"nine",  "kyu - \u4E5D"},
      {"ten",   "ju - \u5341"},
      {"one",   "ichi - \u4E00"},
      {"two",   "ni - \u4E8C"},
      {"three", "san - \u4E09"},
      {"four",  "shi - \u56DB"},
      {"five",  "go - \u4E94"},
      {"six",   "roku - \u516D"},
      {"seven", "shichi - \u4E03"},
      {"eight", "hachi - \u516B"},
      {"nine",  "kyu - \u4E5D"},
      {"ten",   "ju - \u5341"},
      {"one",   "ichi - \u4E00"},
      {"two",   "ni - \u4E8C"},
      {"three", "san - \u4E09"},
      {"four",  "shi - \u56DB"},
      {"five",  "go - \u4E94"},
      {"six",   "roku - \u516D"},
      {"seven", "shichi - \u4E03"},
      {"eight", "hachi - \u516B"},
      {"nine",  "kyu - \u4E5D"},
      {"ten",   "ju - \u5341"},
      {"one",   "ichi - \u4E00"},
      {"two",   "ni - \u4E8C"},
      {"three", "san - \u4E09"},
      {"four",  "shi - \u56DB"},
      {"five",  "go - \u4E94"},
      {"six",   "roku - \u516D"},
      {"seven", "shichi - \u4E03"},
      {"eight", "hachi - \u516B"},
      {"nine",  "kyu - \u4E5D"},
      {"ten",   "ju - \u5341"},
    };
    final Object headers[] = {"English", "Japanese"};
    Runnable runner = new Runnable() {
      public void run() {
        JFrame frame = new JFrame("Table Printing");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        final JTable table = new JTable(rows, headers);
        JScrollPane scrollPane = new JScrollPane(table);
        frame.add(scrollPane, BorderLayout.CENTER);
        JButton button = new JButton("Print");
        ActionListener printAction = new ActionListener() {
          public void actionPerformed(ActionEvent e) {
            try {
              MessageFormat headerFormat = new MessageFormat("Page {0}");
              MessageFormat footerFormat = new MessageFormat("- {0} -");
              table.print(JTable.PrintMode.FIT_WIDTH, headerFormat, footerFormat);
            } catch (PrinterException pe) {
              System.err.println("Error printing: " + pe.getMessage());
            }
          }
        };
        button.addActionListener(printAction);
        frame.add(button, BorderLayout.SOUTH);
        frame.setSize(300, 150);
        frame.setVisible(true);
      }
    };
    EventQueue.invokeLater(runner);
  }
}

应该说比较简单，但是正式报表几乎没法用。

2.通过JasperReport工具来实现打印

目前大部分报表打印应该都是通过JasperReport来实现的，不知道的可以看看之前写的一个教程：JasperReport 个人使用的一些经验

问题是如果表头固定，那么模板还好设计，如果表头不固定呢？那就要自己来通过JasperDesign来绘制了，稍微有点麻烦了，这块自己的处理方式是表头固定的JasperReport，不固定的就直接Swing绘制，就是下面要讲的一种。

3. 通过 print(Graphics g, PageFormat pf, int pageIndex)方法手动绘制

这个方法的好处是基本上所有报表应该都不是问题，关键是绘制起来有些麻烦了，需要手动考虑分页问题，以及字体设置，绘制表头，绘制数据区域，绘制表尾等。

上面三个方法是目前我知道的，第一种几乎就没法在报表中使用，一般是第二种方法，第三种方法是实在用第二种不好实现时使用的。

不知道大伙项目中遇上复杂的报表打印是如何处理的呢？

生成PDF，然后打开PDF阅读器，然后用户爱怎么打印怎么打印。

关键问题是有些时候，用户只要打印，即使我导出成Excel也不成，按钮下去，打印机出来，没有多余步骤！

一般用户都需要打印预览吧？这不就借用PDF阅读器作为打印预览，然后用PDF阅读器的打印命令打印，想必一般用户都能接受吧。