java使用itext为pdf文件设置密码保护详解编程语言

我们可以使用itext的PdfWriter类的setEncryption方法来为pdf文件设置密码

package com.open.pdf; 
 
import java.io.File; 
import java.io.FileOutputStream; 
import java.io.OutputStream; 
import java.util.Date; 
 
import com.itextpdf.text.Document; 
import com.itextpdf.text.Paragraph; 
import com.itextpdf.text.pdf.PdfWriter; 
 
public class GeneratePDF { 
 
    private static String USER_PASS = "Hello123"; 
 
    private static String OWNER_PASS = "Owner123"; 
 
    public static void main(String[] args) { 
        try { 
 
            OutputStream file = new FileOutputStream(new File("D://Test.pdf")); 
 
            Document document = new Document(); 
            PdfWriter writer = PdfWriter.getInstance(document, file); 
 
            writer.setEncryption(USER_PASS.getBytes(), OWNER_PASS.getBytes(), 
                    PdfWriter.ALLOW_PRINTING, PdfWriter.ENCRYPTION_AES_128); 
 
            document.open(); 
            document.add(new Paragraph("Hello World, iText")); 
            document.add(new Paragraph(new Date().toString())); 
 
            document.close(); 
            file.close(); 
 
        } catch (Exception e) { 
 
            e.printStackTrace(); 
        } 
    } 
}