JAVA打印代码

以下是上述教程中一个最简单的例子，这个例子刻画了通过iText生成PDF文件的一般
程序框架。读者只需要在document.open();和document.close();两条语句中间加入自己希望放在PDF文件中的内容即可。该例子只在PDF文件中加了“Hello World“一行文字。

//java中用的代码
Document document = new Document();
try {
PdfWriter.getInstance(document, new FileOutputStream ("Chap0101.pdf"));
document.open();
document.add(new Paragraph("Hello World"));
}
catch(DocumentException de) {
System.err.println(de.getMessage());
}
catch(IOException ioe) {
System.err.println(ioe.getMessage());
}
document.close();

//jsp页面中写的代码

<%@
page import="java.io.*,java.awt.Color,com.lowagie.text.*,com.lowagie.text.pdf.*"%>
<%
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] ); }
%>

//或者通过Servlet生成

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();
}