java 用于加密/解密pdf文件的Java API
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Java API for encrypting / decrypting pdf files
提问by DG.
I need to encrypt and decrypt pdf files. Is there a free or low cost Java API that does that ? Basically I need to hide files from normal users. Any other suggestion on achieving that programatically ?
我需要加密和解密pdf文件。是否有免费或低成本的 Java API 可以做到这一点？基本上我需要对普通用户隐藏文件。关于以编程方式实现这一目标的任何其他建议？
Thanks, Deep
谢谢，深
采纳答案by Frederik
Using iText:
使用iText：
// Assuming you provide the following yourself:
File inputFile;
File outputFile;
String userPassword;
String ownerPassword;
// A bit-field containing file permissions.
int permissions = PDFWriter.ALLOW_PRINTING | PDFWriter.ALLOW_COPY;
PdfReader reader = new PdfReader(inputFile);
PdfEncryptor.encrypt(reader, new FileOutputStream(outputFile),
ENCRYPTION_AES128, userPassword, ownerPassword,
permissions);
Here's the API for PDFEncryptorand PDFWriter(for the permissions).
这是PDFEncryptor和PDFWriter的 API （用于权限）。
回答by Anthony O.
Using PDFBox(based on Decrypt.javacode) :
使用PDFBox（基于Decrypt.java代码）：
PDDocument document = null;
try
{
document = PDDocument.load( infile );
if( document.isEncrypted() )
{
DecryptionMaterial decryptionMaterial = null;
decryptionMaterial = new StandardDecryptionMaterial(password);
document.openProtection(decryptionMaterial);
AccessPermission ap = document.getCurrentAccessPermission();
if(ap.isOwnerPermission())
{
document.setAllSecurityToBeRemoved(true);
document.save( outfile );
}
else
{
throw new IOException(
"Error: You are only allowed to decrypt a document with the owner password." );
}
}
else
{
System.err.println( "Error: Document is not encrypted." );
}
}
finally
{
if( document != null )
{
document.close();
}
}
