我正面临
使用Java从数字签名电子令牌中
NullPointerException
import com.itextpdf.text.Document;
import com.itextpdf.text.DocumentException;
import com.itextpdf.text.Paragraph;
import com.itextpdf.text.Rectangle;
import com.itextpdf.text.pdf.PdfEncryptor;
import com.itextpdf.text.pdf.PdfReader;
import com.itextpdf.text.pdf.PdfSignatureAppearance;
import com.itextpdf.text.pdf.PdfStamper;
import com.itextpdf.text.pdf.PdfWriter;
import com.itextpdf.text.pdf.security.BouncyCastleDigest;
import com.itextpdf.text.pdf.security.CertificateUtil;
import com.itextpdf.text.pdf.security.CrlClient;
import com.itextpdf.text.pdf.security.CrlClientOnline;
import com.itextpdf.text.pdf.security.DigestAlgorithms;
import com.itextpdf.text.pdf.security.ExternalDigest;
import com.itextpdf.text.pdf.security.ExternalSignature;
import com.itextpdf.text.pdf.security.MakeSignature;
import com.itextpdf.text.pdf.security.MakeSignature.CryptoStandard;
import com.itextpdf.text.pdf.security.OcspClient;
import com.itextpdf.text.pdf.security.OcspClientBouncyCastle;
import com.itextpdf.text.pdf.security.PrivateKeySignature;
import com.itextpdf.text.pdf.security.TSAClient;
import com.itextpdf.text.pdf.security.TSAClientBouncyCastle;
import java.io.BufferedReader;
import java.io.File;
import java.io.FileOutputStream;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
import java.io.OutputStream;
import java.io.PrintWriter;
import java.lang.reflect.Constructor;
import java.lang.reflect.InvocationTargetException;
import java.math.BigInteger;
import java.nio.file.CopyOption;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.nio.file.StandardCopyOption;
import java.security.GeneralSecurityException;
import java.security.KeyStoreException;
import java.security.NoSuchAlgorithmException;
import java.security.PrivateKey;
import java.security.Provider;
import java.security.UnrecoverableKeyException;
import java.security.cert.Certificate;
import java.security.cert.CertificateException;
import java.security.cert.CertificateExpiredException;
import java.security.cert.CertificateNotYetValidException;
import java.security.cert.CertificateParsingException;
import java.security.cert.X509Certificate;
import java.text.DateFormat;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Date;
import java.util.Iterator;
import java.util.List;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import javax.swing.JPasswordField;
public class Signature {
public static ArrayList b = new ArrayList();
public static String userName = new com.sun.security.auth.module.NTSystem().getName();
public static String srcPath = null;
public static String destPath = null;
public static String smtp = null;
public static String pin = null;
public static String Mac;
public static String destina;
public static String tempsrc;
public static String temp;
public static PrivateKey pk;
public static DateFormat dateFormat;
public static String line;
public static Document document;
public static String alias = null;
public static BufferedReader bufferedReader;
public static File[] listOfFiles;
public static X509Certificate cert;
public static OcspClient ocspClient;
public static TSAClient tsaClient = null;
public static Certificate[] chain;
public static java.security.KeyStore keyStore;
public static java.io.ByteArrayInputStream pkcs11ConfigStream;
public static sun.security.pkcs11.SunPKCS11 providerPKCS11;
public static java.security.Provider p;
public static JPasswordField pf;
public static String pkcs11Config;
public static final JPanel panel = new JPanel();
public static FileWriter fw;
public static Date date;
public static BigInteger serialNo;
public static void main(String args[]) throws IOException, GeneralSecurityException, DocumentException,
CertificateVerificationException, ParseException {
System.out.println("Digital Signature Process Starts...");
File dpath = new File("C:\\Users\\" + System.getProperty("user.name") + "\\AppData\\Local\\Temp");
if (!dpath.exists()) {
dpath.mkdirs();
}
dateFormat = new SimpleDateFormat("yyyy/MM/dd HH:mm:ss");
date = new Date();
// System.out.println(dateFormat.format(date));
fw = new FileWriter(dpath + "\\log.txt");
try {
fw.write("S01-Application started" + " ~ " + dateFormat.format(date));
} catch (Exception e) {
System.out.println(e);
}
//try {
String my_date = "31/12/9999";
SimpleDateFormat sdf = new SimpleDateFormat("dd/MM/yyyy");
Date strDate = sdf.parse(my_date);
if (new Date().after(strDate)) {
try {
fw.write("\r\n");
fw.write("E01-Appication is out dated,exiting" + " ~ " + dateFormat.format(date));
fw.write("\r\n");
fw.write("S15-Application Ends" + " ~ " + dateFormat.format(date));
fw.close();
} catch (Exception e) {
System.out.println(e);
}
// JOptionPane.showMessageDialog(panel, "Your Application is
// outdated", "Error", JOptionPane.ERROR_MESSAGE);
System.exit(0);
} else {
try {
fw.write("\r\n");
fw.write("S02-Valid Application" + " ~ " + dateFormat.format(date));
} catch (Exception e) {
System.out.println(e);
}
try {
Class<?> pkcs11Class = Class.forName("sun.security.pkcs11.SunPKCS11");
Constructor<?> construct = pkcs11Class.getConstructor(new Class[] { String.class });
pkcs11Config = "C:\\Users\\" + userName + "\\Documents\\Config\\pkcs11.cfg"; // eps2003csp11 //
// TRUSTKEYP11_ND_v34.dll";
// //eMudhraP11_ND_v34.dll"
// ;//
p = (Provider) construct.newInstance(new Object[] { pkcs11Config });
// Security.addProvider(p);
} catch (ClassNotFoundException | NoSuchMethodException | SecurityException | InstantiationException
| IllegalAccessException | IllegalArgumentException | InvocationTargetException e) {
fw.write("\r\n");
fw.write("E03-Digital signature is not installed" + " ~ " + dateFormat.format(date));
fw.write("\r\n");
fw.write("S15-Application Ends" + " ~ " + dateFormat.format(date));
fw.close();
}
try {
fw.write("\r\n");
fw.write("S03-Digital signature is installed perfectly" + " ~ " + dateFormat.format(date));
} catch (Exception e) {
System.out.println(e);
}
try {
java.security.Security.addProvider(p);
keyStore = java.security.KeyStore.getInstance("PKCS11", p);
pf = new JPasswordField();
} catch (Exception e) {
fw.write("\r\n");
fw.write("E04-USB-Key is Not found" + " ~ " + dateFormat.format(date));
fw.write("\r\n");
fw.write("S15-Application Ends" + " ~ " + dateFormat.format(date));
fw.close();
System.exit(0);
}
try {
fw.write("\r\n");
fw.write("S04-USB-key is Detected" + " ~ " + dateFormat.format(date));
} catch (Exception e) {
System.out.println(e);
}
int result = JOptionPane.showConfirmDialog(null, pf, "Please Enter your Digital Signature PIN",
JOptionPane.OK_CANCEL_OPTION);
if (result == JOptionPane.OK_OPTION) {
pin = new String(pf.getPassword());
} else {
//JOptionPane.showMessageDialog(panel, "Process Canceled", "Error", JOptionPane.ERROR_MESSAGE);
fw.write("\r\n");
fw.write("E05-Cancelled the Enter password" + " ~ " + dateFormat.format(date));
fw.write("\r\n");
fw.write("S15-Application Ends" + " ~ " + dateFormat.format(date));
fw.close();
System.exit(0);
}
if (keyStore != null) {
try {
keyStore.load(null, pin.toCharArray());
java.util.Enumeration<String> aliases = keyStore.aliases();
// String alias = null;
ArrayList Certtificates = new ArrayList();
while (aliases.hasMoreElements()) {
alias = aliases.nextElement();
Certtificates.add(alias);
// System.out.println(alias);
}
for (Object Certtificate : Certtificates) {
alias = (String) Certtificate;
//System.out.println(alias);
pk = (PrivateKey) keyStore.getKey(alias, pin.toCharArray());
if (pk != null) {
System.out.println(alias);
chain = keyStore.getCertificateChain(alias);
for (Certificate chain1 : chain) {
X509Certificate cert = (X509Certificate) chain1;
cert.checkValidity();
}
break;
}
}
} catch (IOException | NoSuchAlgorithmException | CertificateException | KeyStoreException
| UnrecoverableKeyException e) {
fw.write("\r\n");
fw.write("E06-Wrong Password entered" + " ~ " + dateFormat.format(date));
fw.write("\r\n");
fw.write("S15-Application Ends" + " ~ " + dateFormat.format(date));
fw.close();
System.exit(0);
}
try {
fw.write("\r\n");
fw.write("S06-Correct Password Entered" + " ~ " + dateFormat.format(date));
} catch (Exception e) {
System.out.println(e);
}
// chain = keyStore.getCertificateChain(alias);
ocspClient = new OcspClientBouncyCastle();
try {
System.out.println(chain);
for (Certificate chain : chain) {
//System.out.println("ASCDCADSEA"+chain);
cert = (X509Certificate) chain;
cert.checkValidity();
//cert.verify(cert.getPublicKey());
Collection<List<?>> List = cert.getSubjectAlternativeNames();
System.out.println("ZZZZZZZZZZZZ" + List);
serialNo = cert.getSerialNumber();
//System.out.println("mmmmmnm"+chain);
System.out.println(serialNo);
Iterator<List<?>> iterator = List.iterator();
while (iterator.hasNext()) {
List<?> test = iterator.next();
smtp = (String) test.get(1);
}
break;
}
} catch (CertificateExpiredException | CertificateNotYetValidException
| CertificateParsingException e) {
fw.write("\r\n");
fw.write("E07-Certificate validity expired" + " ~ " + dateFormat.format(date));
fw.write("\r\n");
fw.write("S15-Application Ends" + " ~ " + dateFormat.format(date));
fw.close();
System.exit(0);
}
try {
fw.write("\r\n");
fw.write("S07-Certificate has validity" + " ~ " + dateFormat.format(date));
} catch (Exception e) {
System.out.println(e);
}
String[] Split = smtp.split("@");
String str = Split[1];
//System.out.println(str);
if ("abc.co.in".equals(str) || "abc.CO.IN".equals(str) || "abc.COM".equals(str)
|| "abc.com".equals(str)) {
fw.write("\r\n");
fw.write("S08-Valid User" + " ~ " + dateFormat.format(date));
} else {
//JOptionPane.showMessageDialog(panel, "Invalid User", "Error", JOptionPane.ERROR_MESSAGE);
fw.write("\r\n");
fw.write("E08-Not Valid User" + " ~ " + dateFormat.format(date));
fw.write("\r\n");
fw.write("S15-Application Ends" + " ~ " + dateFormat.format(date));
fw.close();
System.exit(0);
}
String tsaUrl = CertificateUtil.getTSAURL(cert);
if (tsaUrl != null) {
tsaClient = new TSAClientBouncyCastle(tsaUrl);
return;
}
}
List<CrlClient> crlList = new ArrayList<>();
crlList.add(new CrlClientOnline(chain));
Signature t = new ITEANZ_IDES_V5_TAFE();
ArrayList a = new ArrayList();
try {
FileReader fileReader = new FileReader(
"C:\\Users\\" + userName + "\\AppData\\Local\\Temp\\temp\\temp.txt");
bufferedReader = new BufferedReader(fileReader);
} catch (Exception e) {
fw.write("\r\n");
fw.write("E09-Temporary Text file is not availble" + " ~ " + dateFormat.format(date));
fw.write("\r\n");
fw.write("S15-Application Ends" + " ~ " + dateFormat.format(date));
fw.close();
System.exit(0);
}
try {
fw.write("\r\n");
fw.write("S09-Temporary Text file is availble" + " ~ " + dateFormat.format(date));
} catch (Exception e) {
System.out.println(e);
}
while ((line = bufferedReader.readLine()) != null) {
a.add(line);
}
System.out.println(a.size());
if (a.size() != 3) {
fw.write("\r\n");
fw.write("E10-Data is not maintained Properly" + " ~ " + dateFormat.format(date));
fw.write("\r\n");
fw.write("S15-Application Ends" + " ~ " + dateFormat.format(date));
fw.close();
System.exit(0);
} else {
srcPath = a.get(1).toString();
destPath = a.get(2).toString();
try {
fw.write("\r\n");
fw.write("S10-Data is maintained Properly" + " ~ " + dateFormat.format(date));
} catch (Exception e) {
System.out.println(e);
}
}
// System.out.println(a.get(3).toString());
try {
if (serialNo.toString() == null ? a.get(3).toString().trim() == null
: serialNo.toString().equals(a.get(3).toString().trim())) {
fw.write("\r\n");
fw.write("S11- Authoraised User" + " ~ " + dateFormat.format(date));
} else {
fw.write("\r\n");
fw.write("E11- Un-Authoraised User" + " ~ " + dateFormat.format(date));
fw.write("\r\n");
fw.write("S15-Application Ends" + " ~ " + dateFormat.format(date));
fw.close();
System.exit(0);
}
} catch (Exception e) {
System.out.println(e);
}
File dir = new File(destPath);
dir.mkdirs();
File folder = new File(srcPath);
listOfFiles = folder.listFiles();
if (listOfFiles.length == 0) {
fw.write("\r\n");
fw.write("E12-No files Found inside Input folder" + " ~ " + dateFormat.format(date));
fw.write("\r\n");
fw.write("S15-Application Ends" + " ~ " + dateFormat.format(date));
fw.close();
System.exit(0);
}
if (listOfFiles.length != 0) {
for (File file : listOfFiles) {
if (file.isFile()) {
String userFile = srcPath + "/" + file.getName();
String IndividualFileNAme = file.getName();
String userFile_signed = dir + "/" + file.getName();
t.sign(userFile, IndividualFileNAme, userFile_signed, chain, pk, DigestAlgorithms.SHA256,
p.getName(), CryptoStandard.CMS, "Document Approval", "Bangalore", crlList, ocspClient,
tsaClient, 0);
}
}
}
try {
fw.write("\r\n");
fw.write("S12-File is inside the Input folder" + " ~ " + dateFormat.format(date));
} catch (Exception e) {
System.out.println(e);
}
File srcDir = new File(srcPath);
int numberSrcFiles = srcDir.listFiles().length;
File destDir = new File(destPath);
int numberDestFiles = destDir.listFiles().length;
if (numberDestFiles == numberSrcFiles) {
//JOptionPane.showMessageDialog(panel, "Documents are Signed Successfully", "Success",
//JOptionPane.INFORMATION_MESSAGE);
try {
PrintWriter writer = new PrintWriter(
"C:\\Users\\" + userName + "\\AppData\\Local\\Temp\\temp\\output.txt", "UTF-8");
writer.println("X");
writer.close();
fw.write("\r\n");
fw.write("S14-Documents are Signed Successfully" + " ~ " + dateFormat.format(date));
} catch (Exception e) {
System.out.println(e);
}
} else {
//JOptionPane.showMessageDialog(panel, "Some Documents Are Missing", "Error",
// JOptionPane.ERROR_MESSAGE);
fw.write("\r\n");
fw.write("E15-Some Documents Are Missing" + " ~ " + dateFormat.format(date));
fw.write("\r\n");
fw.write("S15-Application Ends" + " ~ " + dateFormat.format(date));
fw.close();
System.exit(0);
}
System.out.println("Digital Signature Process Ends...");
try {
fw.write("\r\n");
fw.write("S15-Application Ends" + " ~ " + dateFormat.format(date));
fw.close();
} catch (Exception e) {
System.out.println(e);
}
System.exit(0);
}
}
public void sign(String src, String FinalFileName, String dest, Certificate[] chain, PrivateKey pk,
String digestAlgorithm, String provider, CryptoStandard subfilter, String reason, String location,
Collection<CrlClient> crlList, OcspClient ocspClient, TSAClient tsaClient, int estimatedSize)
throws GeneralSecurityException, IOException, DocumentException {
try {
tempsrc = "C:\\Users\\" + userName + "\\AppData\\Local\\Temp\\DigitalSiganture\\Signed_temp.pdf";
temp = "C:\\Users\\" + userName + "\\AppData\\Local\\Temp\\DigitalSiganture\\";
File dir = new File(temp);
dir.mkdirs();
document = new Document();
PdfReader reader6 = new PdfReader(tempsrc);
PdfStamper stamper6 = new PdfStamper(reader6, new FileOutputStream(dest));
stamper6.setEncryption("cp123".getBytes(), "".getBytes(), PdfWriter.ALLOW_COPY,
PdfWriter.ENCRYPTION_AES_256);
stamper6.close();
reader6.close();
PdfWriter.getInstance(document, new FileOutputStream(tempsrc));
document.open();
// step 4
document.add(new Paragraph("Hello World!"));
// step 5
document.close();
PdfReader reader = new PdfReader(src);
Path FROM = Paths.get(src);
Path TO = Paths.get(tempsrc);
// overwrite existing file, if exists
CopyOption[] options = new CopyOption[] { StandardCopyOption.REPLACE_EXISTING,
StandardCopyOption.COPY_ATTRIBUTES };
Files.copy(FROM, TO, options);
int ret = reader.getNumberOfPages();
for (int x = 0; x < ret; x++) {
destina = "Signed_temp" + x + ".pdf";
FileOutputStream os = new FileOutputStream(temp + destina);
PdfReader reader1 = new PdfReader(tempsrc);
tempsrc = temp + destina;
PdfStamper stamper = PdfStamper.createSignature(reader1, os, '\0', null, true);
PdfSignatureAppearance appearance = stamper.getSignatureAppearance();
appearance.setCertificationLevel(PdfSignatureAppearance.NOT_CERTIFIED);
// appearance.setReason(reason);
// appearance.setLocation(location);
String signname = "Sign" + x;
int y = x + 1;
appearance.setAcro6Layers(false);
appearance.setLayer4Text(PdfSignatureAppearance.questionMark);
appearance.setVisibleSignature(new Rectangle(430, 130, 550, 90), y, signname);
ExternalSignature pks = new PrivateKeySignature(pk, digestAlgorithm, provider);
ExternalDigest digest = new BouncyCastleDigest();
MakeSignature.signDetached(appearance, digest, pks, chain, crlList, ocspClient, tsaClient,
estimatedSize, subfilter);
}
try {
fw.write("\r\n");
fw.write("S13-" + FinalFileName + " " + "Signed Successfully" + " ~ " + dateFormat.format(date));
} catch (Exception e) {
System.out.println(e);
}
Path FROM1 = Paths.get(temp + destina);
Path TO1 = Paths.get(dest);
//overwrite existing file, if exists
CopyOption[] options1 = new CopyOption[] { StandardCopyOption.REPLACE_EXISTING,
StandardCopyOption.COPY_ATTRIBUTES };
Files.copy(FROM1, TO1, options1);
/*
* //PdfReader.unethicalreading = true; PdfReader reader5=new PdfReader(temp +
* destina);
*
* PdfEncryptor.encrypt(reader5, new FileOutputStream(dest), null, null,
* PdfWriter.ALLOW_SCREENREADERS, true);
*/
} catch (IOException | GeneralSecurityException | DocumentException e) {
//JOptionPane.showMessageDialog(panel, e, "Error", JOptionPane.ERROR_MESSAGE);
fw.write("\r\n");
fw.write("E14-" + FinalFileName + "Format mismatch or File Crashed " + " ~ " + dateFormat.format(date));
fw.write("\r\n");
fw.write("S15-Application Ends" + " ~ " + dateFormat.format(date));
fw.close();
System.exit(0);
}
}
}
NullPointerException在Iterator<List<?>> iterator = List.iterator();
在程序执行期间，证书值会在读取时出现，但是当我尝试将其存储在List中时，它将变成null。实际上，我想阅读存储有证书的数字签名的USB加密狗，并且需要将签名放入特定位置的PDF文件中。
在读取USB Epass2003时需要对代码进行一些修正
答案 0 :(得分：0)
在代码的这一部分：
Collection<List<?>> List = cert.getSubjectAlternativeNames();
方法getSubjectAlternativeNames()返回null导致NPE。观察一下，在Java中，变量的名称通常以小写字母开头，名称为List的列表很奇怪
答案 1 :(得分：0)
方法.iterator()是实例方法，不能不能称为静态方法。似乎您应该致电List.Iterator()时正在致电someList.iterator()。
只需遍历List，就可以
List<Integer> integerList = Arrays.asList(1, 2, 3, 4);
for (Integer x : integerList)
System.out.println(x);