java jsp生成pdf_如何使用jsp servlet输出iText生成的pdf

使用itext生成pdf

如果每次都在服务端生成一个PDF文件给用户，不仅麻烦，而且浪费服务器资源，最好的方法就是以二进制流的形式输送到客户端。

1)JSP输出：

response.setContentType( "application/pdf" );

Document document = new Document();

ByteArrayOutputStream buffer= new ByteArrayOutputStream();

PdfWriter writer=PdfWriter.getInstance( document, buffer );

document.open();

document.add(new Paragraph("Hello World"));

document.close();

DataOutput output =new DataOutputStream( response.getOutputStream() );

byte[] bytes = buffer.toByteArray();

response.setContentLength(bytes.length);

for( int i = 0;i < bytes.length;i++ ){

output.writeByte( bytes[i] );

}

%>

2)servlet输出，稍微改造下就可以使用在struts中：

import java.io.*;

import javax.servlet.*;

import javax.servlet.http.*;

import com.lowagie.text.*;

import com.lowagie.text.pdf.*;

public void doGet

(HttpServletRequest request,

HttpServletResponse response)

throws IOException,ServletException

{

Document document =

new Document(PageSize.A4, 36,36,36,36);

ByteArrayOutputStream ba

= new ByteArrayOutputStream();

try

{

PdfWriter writer =

PdfWriter.getInstance(document, ba);

document.open();

document.add(new

Paragraph("Hello World"));

}

catch(DocumentException de)

{

de.printStackTrace();

System.err.println

("A Document error:" +de.getMessage());

}

document.close();

response.setContentType

("application/pdf");

response.setContentLength(ba.size());

ServletOutputStream out

= response.getOutputStream();

ba.writeTo(out);

out.flush();

}