J2EE使用iText将数据保存为PDF文档

在B/S结构的项目中，经常需要将一些数据导出为PDF文档，项目中我们使用的就是iText包，该包可以从其官方网上下载： http://www.lowagie.com/iText/  。

下面就来讲一下具体的使用方法。

1、首先我们建一个叫做DbgridColumn的Java类，用来表示标题信息，具体字段如图。

 

java 代码

List columns = new ArrayList();

DbgridColumn column = new DbgridColumn();
column.setProperty = "DM";
column.setCaption  = "代码";
column.setWidth    = 35;
columns.add(column);

column.setProperty = "MC";
column.setCaption  = "名称";
column.setWidth    = 175;
columns.add(column);

2、我们需要构建演示数据，数据列表与Java构建函数。

 

java 代码

Collection collection = new ArrayList();

Map map = new HashMap();
map.put("DM",new String("01");
map.put("MC",new String("设置成功");
collection.add(map);

map.put("DM",new String("02");
map.put("MC",new String("中继命令没有返回");
collection.add(map);

map.put("DM",new String("03");
map.put("MC",new String("设置内容非法");
collection.add(map);
map.put("DM",new String("04");
map.put("MC",new String("密码权限不足");
collection.add(map);

map.put("DM",new String("05");
map.put("MC",new String("无此数据项");
collection.add(map);

map.put("DM",new String("06");
map.put("MC",new String("命令时间失效");
collection.add(map);

map.put("DM",new String("07");
map.put("MC",new String("目标地址不存在");
collection.add(map);

map.put("DM",new String("08");
map.put("MC",new String("发送失败");
collection.add(map);

map.put("DM",new String("09");
map.put("MC",new String("短消息帧太长");
collection.add(map);

  

3、将上面格式的数据转换为iText的PdfPTable格式。

java 代码

public class PdfReport extends ReportModal
{

   public PdfReport(OutputStream out,DbgridModal modal)
   {
      this.out = out;
this.modal = modal;
   }

   public PdfReport()
{ }

   public void out()
   {
Document document = new Document();
      try
{
        public class PdfReport extends ReportModal
{

   public PdfReport(OutputStream out,DbgridModal modal)
   {
      this.out = out;
 this.modal = modal;
   }

   public PdfReport()
 {
   }
/* 输出 */
   public void out()
   {
     Document document = new Document();
      try
     {
         PdfWriter.getInstance(document, out);
      document.open();
     document.add(DbgridToPdfTable(modal.columns,modal.collection));
 }
      catch (DocumentException e)
    {
       throw new Error(e.getMessage(), e);
      }
  catch (IOException e)
      {
         throw new Error(e.getMessage(), e);
    }
   if(document.isOpen())
   {
            document.close();
      }


  public PdfPTable  DbgridToPdfTable(List columns,Collection collection)
  throws BadElementException,DocumentException,IOException
 {
      int columnsCount = columns.size();
  int rowsCount = collection.size();
      //创建Pdf Table
   PdfPTable table = new PdfPTable(columnsCount);
  //table总宽度
table.setTotalWidth((float)getTotalWidth(columns));
      table.setWidths(getWidths(columns));
      //每列之间的间隔
table.setSpacingBefore(Float.parseFloat("1.0"));
//使用中文字符，要支持中文字符，还需要在其官方网站下载iTextAsian.jar和iTextAsianCmaps.jar 两个包
 BaseFont bfChinese = BaseFont.createFont("STSong-Light", "UniGB-UCS2-H", BaseFont.NOT_EMBEDDED);
      com.lowagie.text.Font FontChinese = new com.lowagie.text.Font(bfChinese, 9, com.lowagie.text.Font.NORMAL);
      //开始写标题
  for (int i=0;i
      {
         DbgridColumn dbgridColumn = (DbgridColumn)columns.get(i);
         //创建单元格
 PdfPCell cell = new PdfPCell(new Phrase(dbgridColumn.getCaption(), FontChinese ));
         //标题的背景颜色
      cell.setBackgroundColor(new Color(212,208,200));
         //左右对齐方式
         cell.setHorizontalAlignment(getCellAlign(dbgridColumn.getAlign()));
         //垂直对齐方式默认为中间对齐
         cell.setVerticalAlignment(Element.ALIGN_MIDDLE);
         table.addCell(cell);
      }

   //写表格数据
      Object[] objects = (Object[])collection.toArray();
      for (int j=0;j,@gd
E}  {
         Map map = (Map)objects[j];
         for (int i=0;i&Uo(}         {
             String value = "";
DbgridColumn dbgridColumn = (DbgridColumn)columns.get(i);
             //根据字段名取数据
   Object bean = map.get(dbgridColumn.getProperty());
             //getRealValue函数是对具体的一些数据类型(比如日期、double、integer等)进行格式化处理，如果为null，则返回空字符串
 value = getRealValue(bean,dbgridColumn);
  //创建单元格
 PdfPCell cell = new PdfPCell(new Phrase(value, FontChinese ));
 //对齐方式
cell.setHorizontalAlignment(getCellAlign(dbgridColumn.getAlign()));
  cell.setVerticalAlignment(Element.ALIGN_TOP);
      table.addCell(cell);
         }
   }

      return table;
   }
 /* 把字符串型对齐方式 left,right,center 转化为pdf格式的对齐方式 */
 public int getCellAlign(String align)
   {
      if (align==null)
      {
return Cell.ALIGN_LEFT;
      }
      if (align.toLowerCase().equals("left"))
 {
return Cell.ALIGN_LEFT;
      }
   if (align.toLowerCase().equals("right"))
{
         return Cell.ALIGN_RIGHT;
      }
  if (align.toLowerCase().equals("center"))
  {
return Cell.ALIGN_CENTER;
 }
 return Cell.ALIGN_LEFT;

/* 返回一个int型的数组，存放每列的宽度 */
   public int[] getWidths(java.util.List cols)
 {
  int widths[]=new int[cols.size()];
      for (int i=0;i
      {
    DbgridColumn dbgridColumn = (DbgridColumn)cols.get(i);
         widths[i] = dbgridColumn.getWidth();
      }
    return widths;
   }
 /* 返回表格的总宽度 */
public int getTotalWidth(java.util.List cols)
  {
int totalwidth = 0;
 for (int i=0;i2N    {
    DbgridColumn dbgridColumn = (DbgridColumn)cols.get(i);
         totalwidth = totalwidth + dbgridColumn.getWidth();
     }
  return totalwidth;
   }
 PdfWriter.getInstance(document, out);
      document.open();
    document.add(DbgridToPdfTable(modal.columns,modal.collection));
    }
      catch (DocumentException e)
     {
       throw new Error(e.getMessage(), e);
      }
    catch (IOException e)
      {
         throw new Error(e.getMessage(), e);
     }
   if(document.isOpen())
    {
            document.close();
      }

 public PdfPTable  DbgridToPdfTable(List columns,Collection collection)
     throws BadElementException,DocumentException,IOException
   {
      int columnsCount = columns.size();
   int rowsCount = collection.size();
 //创建Pdf Table
   PdfPTable table = new PdfPTable(columnsCount);
    //table总宽度
  table.setTotalWidth((float)getTotalWidth(columns));
//每列的宽度
 table.setWidths(getWidths(columns));
 //每列之间的间隔
  table.setSpacingBefore(Float.parseFloat("1.0"));
    //使用中文字符，要支持中文字符，还需要在其官方网站下载iTextAsian.jar和iTextAsianCmaps.jar 两个包
BaseFont bfChinese = BaseFont.createFont("STSong-Light", "UniGB-UCS2-H", BaseFont.NOT_EMBEDDED);
com.lowagie.text.Font FontChinese = new com.lowagie.text.Font(bfChinese, 9, com.lowagie.text.Font.NORMAL);
//开始写标题
    for (int i=0;i
      {
 DbgridColumn dbgridColumn = (DbgridColumn)columns.get(i);
//创建单元格
     PdfPCell cell = new PdfPCell(new Phrase(dbgridColumn.getCaption(), FontChinese ));
//标题的背景颜色
       cell.setBackgroundColor(new Color(212,208,200));
 //左右对齐方式
cell.setHorizontalAlignment(getCellAlign(dbgridColumn.getAlign()));
  //垂直对齐方式默认为中间对齐
 cell.setVerticalAlignment(Element.ALIGN_MIDDLE);
 table.addCell(cell);
 }

    //写表格数据
Object[] objects = (Object[])collection.toArray();
 for (int j=0;j,@gd
E}Guest      {
Map map = (Map)objects[j];  for (int i=0;      {
String value = "";
 DbgridColumn dbgridColumn = (DbgridColumn)columns.get(i);
//根据字段名取数据
            Object bean = map.get(dbgridColumn.getProperty());
//getRealValue函数是对具体的一些数据类型(比如日期、double、integer等)进行格式化处理，如果为null，则返回空字符串
value = getRealValue(bean,dbgridColumn);
             //创建单元格
             PdfPCell cell = new PdfPCell(new Phrase(value, FontChinese ));
            //对齐方式
             cell.setVerticalAlignment(Element.ALIGN_TOP);
   table.addCell(cell);

      return table;
   }
  /* 把字符串型对齐方式 left,right,center 转化为pdf格式的对齐方式 */
 public int getCellAlign(String align)
   {
      if (align==null)
      {
     return Cell.ALIGN_LEFT;
      }
      if (align.toLowerCase().equals("left"))
     {
       return Cell.ALIGN_LEFT;
      }
     if (align.toLowerCase().equals("right"))
      {
         return Cell.ALIGN_RIGHT;
      }
   if (align.toLowerCase().equals("center"))
     {
 return Cell.ALIGN_CENTER;
    }
    return Cell.ALIGN_LEFT;
   }

  /* 返回一个int型的数组，存放每列的宽度 */
   public int[] getWidths(java.util.List cols)
  {
    int widths[]=new int[cols.size()];
      for (int i=0;i
      {
     DbgridColumn dbgridColumn = (DbgridColumn)cols.get(i);
  widths[i] = dbgridColumn.getWidth();
      }
  return widths;
   }
 /* 返回表格的总宽度 */
  public int getTotalWidth(java.util.List cols)
  {
   int totalwidth = 0;
    for (int i=0;i2    {
     DbgridColumn dbgridColumn = (DbgridColumn)cols.get(i);
 totalwidth = totalwidth + dbgridColumn.getWidth();
  return totalwidth;
   }

4、通过Servlet生成pdf文档，并弹出下载对话框。

java 代码

public class ReportServlet extends HttpServlet

public ReportServlet()
   {
 }

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