reading pdf through java

i am reading pdf through java but problem is like that i am reading 500 pages at that time they can read only 496 pages plz tell me what can i do
my code is bellow

public class pdf1 {

	
	public static void main(String[] args) throws SQLException, ClassNotFoundException {
		try {

			PdfReader reader = new PdfReader("me1.pdf");
			
//			int n = reader.getNumberOfPages();
			 File outFile = new File("b.csv");
			int n=500;
			int count=0;
			 BufferedWriter writer = new BufferedWriter(new FileWriter(outFile));
			
			 for(int i=1;i<=n;i++)
			 {
			 String str=PdfTextExtractor.getTextFromPage(reader, i);
			 System.out.println(str);
			 writer.write(str);
			 count++;
			 }
			 System.out.println(count);

	} catch (IOException e) {
			e.printStackTrace();
		}

	}

}