今天忙了一天，终于把打印预览的功能给实现了，因为昨天写了两个打印的方法，感觉到既然打印要预览才可以的
一：Excel打印预览：
首先还是一样，引入JCom.jar，并把bin文件放入JDK/bin目录下才可以
代码如下： 

/**
* 引入JCom操作Excel的jar
*/
import jp.ne.so_net.ga2.no_ji.jcom.ReleaseManager;
import jp.ne.so_net.ga2.no_ji.jcom.excel8.ExcelApplication;
import jp.ne.so_net.ga2.no_ji.jcom.excel8.ExcelWorkbook;
import jp.ne.so_net.ga2.no_ji.jcom.excel8.ExcelWorkbooks;
import jp.ne.so_net.ga2.no_ji.jcom.excel8.ExcelWorksheet;
/**
* 预览Excel的类
* @author tianmaochun
*
*/
public class PrintViewExcel{

/**
* 实线Excel预览的类
* @param fileName[图片的路径]
*
*/
public void getExcelView(String fileName){
ReleaseManager rm = new ReleaseManager();
try{
//创建可加载的组件
ExcelApplication excel = new ExcelApplication(rm);
//创建工作薄对象
ExcelWorkbooks xlBooks = excel.Workbooks();
//打开工作薄
ExcelWorkbook xlBook = xlBooks.Open(fileName);
//打印
ExcelWorksheet xlSheet = excel.ActiveSheet();
//显示Excel
excel.Visible(true);
//输出页面
xlSheet.PrintOut(1,1,1,true);
//关闭
xlBook.Close(false, null, false);
excel.Quit();
}catch (Exception e) {
e.printStackTrace();

}finally {
rm.release();
}
}
/**
* @param args
*/
public static void main(String[] args) {
// TODO Auto-generated method stub
PrintViewExcel prview = new PrintViewExcel();
prview.getExcelView("f:/tian.xls");

}

}


二：打印预览图片： 

package com.gyhq.soft;

import java.awt.BasicStroke;
import java.awt.Container;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Image;
import java.awt.Toolkit;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.print.PageFormat;
import java.awt.print.Printable;
import java.awt.print.PrinterException;

import javax.swing.JButton;
import javax.swing.JDialog;
import javax.swing.JFrame;
import javax.swing.JPanel;
/**
* 打印预览窗体类
* @author tianmaochun
*
*/
public class PrintViewImage extends JDialog implements Printable,ActionListener{

//初始化页面的大小和方向
private PageFormat pf = null;
private double sca =1;
//初始化一个img对象
private Image img = null;
//定义一个Button
private JButton but = null;
//定义一个图片的路径
String fileName = null;
/**
* 构造方法
*/
public PrintViewImage(String fileName){
this.fileName = fileName;
initFrame();
}
public void getView(){
//实例化
pf = new PageFormat();
//获取预览图片的路径
img = Toolkit.getDefaultToolkit().getImage(fileName);
}
/**
* 初始化页面的方法
*/
private void initFrame() {
//定义一个容器
Container container = this.getContentPane();
this.setTitle("打印预览");
this.setResizable(false);
but = new JButton("打印");
but.setBounds(600, 715, 100, 30);
but.addActionListener(this);
this.add(but);
//实例化预览类
PreviewCanvas priView = new PreviewCanvas();
//添加到容器之中去
container.add(priView);
//显示
this.pack();
this.setLocationRelativeTo(null);
this.setVisible(true);
//关闭
this.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
}
/**
* 预览类
* @author tianmaochun
*
*/
private class PreviewCanvas extends JPanel {
//private static final long serialVersionUID = 20110208L;
/**
* 构造方法
*/
public PreviewCanvas() {
//设置窗体的大小
this.setPreferredSize(new Dimension(800, 750));
}

/**
* 画预览区域
*/
public void paintComponent(Graphics g) {
super.paintComponent(g);
Graphics2D g2 = (Graphics2D) g;
g2.translate(10, 10);
//获取页面宽度
double width = pf.getWidth();
//获取页面的高度
double height = pf.getHeight();
//返回左上方X
double imageableX = pf.getImageableX();
//返回左上方Y
double imageableY = pf.getImageableY();
//返回页面可成像区域的宽度
double imageableWidth = pf.getImageableWidth();
//返回页面可成像区域的高度
double imageableHeight = pf.getImageableHeight();
if (width > 800 || height >700) {
double scaleWidth = (double) 800 / width;
double scaleHeight = (double) 700 / height;
sca = scaleWidth < scaleHeight ? scaleWidth : scaleHeight;
width = width * sca;
height = height * sca;
imageableX = imageableX * sca;
imageableY = imageableY * sca;
imageableWidth = imageableWidth * sca;
imageableHeight = imageableHeight * sca;
}
//画一个实线的矩形
g2.drawRect(0, 0, (int) width+200, (int) height);
float[] dash = { 5f, 5f };
//定义虚线类型
g2.setStroke(new BasicStroke(1f, BasicStroke.CAP_ROUND,
BasicStroke.JOIN_ROUND, 10f, dash, 0f));
//画虚线矩形
g2.drawRect((int) (imageableX - 1), (int) (imageableY - 1),
(int) (imageableWidth + 2)+200, (int) (imageableHeight + 2));
try {
//画相应的图片在框中
PrintViewImage.this.print(g2, pf, 0);
} catch (PrinterException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
/**
* 复写Printtable的方法
*/
@Override
public int print(Graphics graphics, PageFormat pageFormat, int pageIndex)
throws PrinterException {
//获取最左X坐标
double imageableX = pageFormat.getImageableX();
//获取最左Y坐标
double imageableY = pageFormat.getImageableY();
//获取图片的宽度
int imgWidth = img.getWidth(this);
//获取图片的高度
int imgHeight = img.getHeight(this);
//判断图片的大小是否大于页面的宽度
if(imgWidth>800||imgHeight>750){
//规定大小画图片在框中
graphics.drawImage(img, (int) (imageableX * sca),(int) (imageableY * sca), 610,
570, this);
}else{
//根据图片大小预览
graphics.drawImage(img, (int) (imageableX * sca),(int) (imageableY * sca), (int) (imgWidth * sca),
(int) (imgHeight * sca), this);
}
if (pageIndex == 0) {
//从print页面中返回
return Printable.PAGE_EXISTS;
} else {
//返回呈现的页面
return Printable.NO_SUCH_PAGE;
}

}
/**
* 按钮事件
*/
@Override
public void actionPerformed(ActionEvent e) {
// TODO Auto-generated method stub
if(e.getSource()==but){
//实例化相应的类并调用打印相应的方法
PrintImage dp = new PrintImage();
dp.drawImage(fileName);
}

}
/**
* 主函数的方法
* @param args
*/
public static void main(String[] args){
new PrintViewImage("img/tt.gif").getView();
}
}