我知道这可能是我要放在这里的愚蠢问题，因为我是一个完整的java菜鸟。也许你们可以帮助我解决这个问题。
我正在开发一个应用程序，用户需要在pdf格式的jsp页面上显示结果，并且pdf在HTTP请求中作为输出流生成，意味着当用户点击按钮（在jsp上）到生成带有结果的PDF，即PDF即时生成并发送到客户端浏览器。
使用iText，我可以动态生成自定义生成的pdf
以下是代码段
public class PdfSample extends HttpServlet {
public PdfSample() {
super();
}
//connection to DB.... code goes here.....
public void doPost(HttpServletRequest req, HttpServletResponse resp)
throws ServletException, IOException {
doGet(req, resp);
}
public void doGet(HttpServletRequest req, HttpServletResponse resp)
throws javax.servlet.ServletException, java.io.IOException {
DocumentException ex = null;
ByteArrayOutputStream baosPDF = null;
try {
baosPDF = generatePDFDocumentBytes(req, this.getServletContext());
StringBuffer sbFilename = new StringBuffer();
sbFilename.append("filename_");
sbFilename.append(System.currentTimeMillis());
sbFilename.append(".pdf");
resp.setHeader("Cache-Control", "max-age=30");
resp.setContentType("application/pdf");
StringBuffer sbContentDispValue = new StringBuffer();
sbContentDispValue.append("inline");
sbContentDispValue.append("; filename=");
sbContentDispValue.append(sbFilename);
resp.setHeader("Content-disposition", sbContentDispValue.toString());
resp.setContentLength(baosPDF.size());
ServletOutputStream sos;
sos = resp.getOutputStream();
baosPDF.writeTo(sos);
sos.flush();
} catch (DocumentException dex) {
resp.setContentType("text/html");
PrintWriter writer = resp.getWriter();
writer.println(this.getClass().getName() + " caught an exception: "
+ dex.getClass().getName() + "<br>");
writer.println("<pre>");
dex.printStackTrace(writer);
writer.println("</pre>");
} finally {
if (baosPDF != null) {
baosPDF.reset();
}
}
}
protected ByteArrayOutputStream generatePDFDocumentBytes(
final HttpServletRequest req, final ServletContext ctx)
throws DocumentException
{
Document doc = new Document();
ByteArrayOutputStream baosPDF = new ByteArrayOutputStream();
PdfWriter docWriter = null;
try {
docWriter = PdfWriter.getInstance(doc, baosPDF);
doc.addAuthor("Sample");
doc.addCreationDate();
doc.addProducer();
doc.addCreator("Sample");
doc.addTitle("Sample Report");
doc.setPageSize(PageSize.LETTER);
doc.open();
String strServerInfo = ctx.getServerInfo();
if (strServerInfo != null) {
}
doc.add(makeHTTPParameterInfoElement(req));
} catch (DocumentException dex) {
baosPDF.reset();
throw dex;
} finally {
if (doc != null) {
doc.close();
}
if (docWriter != null) {
docWriter.close();
}
}
if (baosPDF.size() < 1) {
throw new DocumentException("document has " + baosPDF.size()
+ " bytes");
}
return baosPDF;
}
protected Element makeHTTPParameterInfoElement(final HttpServletRequest req) {
Table tab = null;
tab = makeTable("", "White Color Car", "Black Color Car", "Total");
return (Element) tab;
}
private static Table makeTable(final String firstColumnTitle,
final String secondColumnTitle, final String thirdColumnTitle,
final String fourthColumnTitle) {
Paragraph paragraph, paragraph1;
int val1 = 0;
int val2 = 0;
int val3 = 0;
int val4 = 0;
Table tab = null;
try {
tab = new Table(4);
} catch (BadElementException ex) {
throw new RuntimeException(ex);
}
Cell c = null;
try {
paragraph = new Paragraph("Car Report");
paragraph.setAlignment(1);
c = new Cell(paragraph);
c.setColspan(tab.getColumns());
} catch (Exception e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
}
tab.setBorderWidth(1);
tab.setBorderColor(Color.BLACK);
tab.setPadding(2);
tab.setSpacing(3);
tab.setBackgroundColor(Color.WHITE);
tab.addCell(c);
tab.addCell(new Cell(firstColumnTitle));
tab.addCell(new Cell(secondColumnTitle));
tab.addCell(new Cell(thirdColumnTitle));
tab.addCell(new Cell(fourthColumnTitle));
tab.endHeaders();
String startDate1 = "01/06/2011";
String endDate1 = "11/09/2011";
SimpleDateFormat sdf1 = new SimpleDateFormat("dd/MM/yyyy");
try {
Date startDate = sdf1.parse(startDate1);
Date endDate = sdf1.parse(endDate1);
java.sql.Date sdate = new java.sql.Date(startDate.getTime());
java.sql.Date edate = new java.sql.Date(endDate.getTime());
String newWhiteColor = "select count(*) from .......";
String newBlackColor = "select count(*) from .......";
String totalWhiteColor= "select count(*) from .....";
String totalBlackColor = "select count(*) from .......";
Connection connection = null;
PreparedStatement preparedStatement = null;
PreparedStatement preparedStatement1 = null;
PreparedStatement preparedStatement2 = null;
PreparedStatement preparedStatement3 = null;
ResultSet resultSet = null;
ResultSet resultSet1 = null;
ResultSet resultSet2 = null;
ResultSet resultSet3 = null;
connection = getSimpleConnection1();
// New Car recently sold out - White Color
preparedStatement = connection
.prepareStatement(newWhiteColor);
resultSet = preparedStatement.executeQuery();
while (resultSet.next()) {
val1 = resultSet.getInt(1);
}
// New Car recently sold out - Black Color
preparedStatement3 = connection
.prepareStatement(newBlackColor);
resultSet3 = preparedStatement3.executeQuery();
while (resultSet3.next()) {
val2 = resultSet3.getInt(1);
}
// Total White Color cars sold out
preparedStatement1 = connection
.prepareStatement(totalWhiteColor);
resultSet1 = preparedStatement1.executeQuery();
while (resultSet1.next()) {
val3 = resultSet1.getInt(1);
}
// Total Black Color cars sold out
preparedStatement2 = connection
.prepareStatement(totalBlackColor);
resultSet2 = preparedStatement2.executeQuery();
while (resultSet2.next()) {
val4 = resultSet2.getInt(1);
}
Integer newWhite = val1;
Integer newBlack = val2;
Integer totalWhite = val3;
Integer totalBlack = val4;
Integer totalNewCars = newWhite + new Black;
Integer totalCars= totalWhite + totalBlack ;
tab.addCell(new Cell("New Cars Sold Out"));
tab.addCell(new Cell(newWhite.toString()));
tab.addCell(new Cell(newBlack.toString()));
tab.addCell(new Cell(totalNewCars.toString()));
tab.addCell(new Cell("Total Cars Sold out"));
tab.addCell(new Cell(totalWhite.toString()));
tab.addCell(new Cell(totalBlack.toString()));
tab.addCell(new Cell(totalCars.toString()));
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return tab;
}
}
上面的代码通过建立连接并在单元格中显示来从数据库中获取数据（计数）。使用上面的代码，我可以在飞行和输出上创建pdf，如下所示。
--------------------------------------------------------------------------------------------------
Car Report
--------------------------------------------------------------------------------------------------
| White Color Car |Black Color Car | Total
--------------------------------------------------------------------------------------------------
New Cars Sold out| 5 | 8 | 13
--------------------------------------------------------------------------------------------------
Total Cars Sold Out| 6 | 4 | 10
--------------------------------------------------------------------------------------------------
查询1）如何在中心对齐汽车报告？
查询2）数据和文本正在单元格内显示，如何将单元格的边框设置为“0”。
查询3）如何为特定单元格（空白单元格）着色？
查询4）是否可以在pdf标题的顶部插入图片？
任何帮助都将非常感谢!!!!!
答案 0 :(得分：0)
查询1） 如何在中心对齐汽车报告？
解决方案：c.setHorizontalAlignment(Element.ALIGN_CENTER);