java.io.IOException : 문서에 페이지가 없습니다

Question

이름이 Hello World이고 오류가 발생하는 PDF를 작성하려고합니다. java.io.IOException : 문서에 페이지가 없습니다. 여기

는 내 서블릿 코드 : iText를에 나는 새로운 오전

package org.ritesh; 

import java.io.ByteArrayOutputStream; 
import java.io.IOException; 

import javax.servlet.ServletOutputStream; 
import javax.servlet.http.*; 

import com.lowagie.text.Document; 
import com.lowagie.text.DocumentException; 
import com.lowagie.text.Paragraph; 
import com.lowagie.text.pdf.PdfWriter; 

@SuppressWarnings("serial") 
public class PdfmakeServlet extends HttpServlet { 
    public void doGet(HttpServletRequest req, HttpServletResponse resp) 
      throws IOException { 
     resp.setContentType("application/pdf"); 


     Document document =new Document(); 
      ByteArrayOutputStream baos = new ByteArrayOutputStream(); 
      try { 
       PdfWriter.getInstance(document, baos); 
      } catch (DocumentException e) { 
       // TODO Auto-generated catch block 
       e.printStackTrace(); 
      } 
      document.open(); 

       try { 
        document.add(new Paragraph("Hello WOrld ")); 
       } catch (DocumentException e) { 
        // TODO Auto-generated catch block 
        e.printStackTrace(); 
       } 



      resp.setContentLength(baos.size()); 

      // write ByteArrayOutputStream to ServletOutputStream 
      ServletOutputStream out = resp.getOutputStream(); 
      baos.writeTo(out); 

      out.flush(); 
      out.close(); 
      document.close(); 
    } 
} 

이는 GAE 애플 리케이션 그래서이 iText의 호환 라이브러리를 추가됩니다하지만 점점이 오류

java.io.IOException: The document has no pages. 
    at com.lowagie.text.pdf.PdfPages.writePageTree(Unknown Source) 
    at com.lowagie.text.pdf.PdfWriter.close(Unknown Source) 
    at com.lowagie.text.pdf.PdfDocument.close(Unknown Source) 
    at com.lowagie.text.Document.close(Unknown Source) 
    at org.ritesh.PdfmakeServlet.doGet(PdfmakeServlet.java:48) 
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:617) 
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:717) 
    at org.mortbay.jetty.servlet.ServletHolder.handle(ServletHolder.java:511) 
    at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1166) 
    at com.google.appengine.tools.development.HeaderVerificationFilter.doFilter(HeaderVerificationFilter.java:35) 
    at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157) 
    at com.google.appengine.api.blobstore.dev.ServeBlobFilter.doFilter(ServeBlobFilter.java:60) 
    at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157) 
    at com.google.apphosting.utils.servlet.TransactionCleanupFilter.doFilter(TransactionCleanupFilter.java:43) 
    at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157) 
    at com.google.appengine.tools.development.StaticFileFilter.doFilter(StaticFileFilter.java:122) 
    at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157) 
    at com.google.appengine.tools.development.BackendServersFilter.doFilter(BackendServersFilter.java:97) 
    at org.mortbay.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1157) 
    at org.mortbay.jetty.servlet.ServletHandler.handle(ServletHandler.java:388) 
    at org.mortbay.jetty.security.SecurityHandler.handle(SecurityHandler.java:216) 
    at org.mortbay.jetty.servlet.SessionHandler.handle(SessionHandler.java:182) 
    at org.mortbay.jetty.handler.ContextHandler.handle(ContextHandler.java:765) 
    at org.mortbay.jetty.webapp.WebAppContext.handle(WebAppContext.java:418) 
    at com.google.appengine.tools.development.DevAppEngineWebAppContext.handle(DevAppEngineWebAppContext.java:78) 
    at org.mortbay.jetty.handler.HandlerWrapper.handle(HandlerWrapper.java:152) 
    at com.google.appengine.tools.development.JettyContainerService$ApiProxyHandler.handle(JettyContainerService.java:369) 
    at org.mortbay.jetty.handler.HandlerWrapper.handle(HandlerWrapper.java:152) 
    at org.mortbay.jetty.Server.handle(Server.java:326) 
    at org.mortbay.jetty.HttpConnection.handleRequest(HttpConnection.java:542) 
    at org.mortbay.jetty.HttpConnection$RequestHandler.headerComplete(HttpConnection.java:923) 
    at org.mortbay.jetty.HttpParser.parseNext(HttpParser.java:547) 
    at org.mortbay.jetty.HttpParser.parseAvailable(HttpParser.java:212) 
    at org.mortbay.jetty.HttpConnection.handle(HttpConnection.java:404) 
    at org.mortbay.io.nio.SelectChannelEndPoint.run(SelectChannelEndPoint.java:409) 
    at org.mortbay.thread.QueuedThreadPool$PoolThread.run(QueuedThreadPool.java:582) 

하나는 수 이 오류를 제거하는 방법을 알려주십시오.

Answer 1

문서가 닫힌 후에 만 ​​ByeArrayOutputStream을 서블릿 OutputStream에 할당 할 것을 제안합니다. document.close() 명령 전에 ByteArrayOutputStream에는 0 크기가 있습니다.