Question

我正在研究用iText签署pdf的另一个代码。库是新的，下载的是代码源。我是java和iText的新手。对不起代码中的长篇帖子：

package c2_01_signhelloworld;

import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.security.GeneralSecurityException;
import java.security.KeyStore;
import java.security.PrivateKey;
import java.security.Security;
import java.security.cert.Certificate;

import org.bouncycastle.jce.provider.BouncyCastleProvider;

import com.itextpdf.text.DocumentException;
import com.itextpdf.text.Rectangle;
import com.itextpdf.text.pdf.PdfReader;
import com.itextpdf.text.pdf.PdfSignatureAppearance;
import com.itextpdf.text.pdf.PdfStamper;
import com.itextpdf.text.pdf.security.BouncyCastleDigest;
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.PrivateKeySignature;

public class C2_01_SignHelloWorld {

    public static final String KEYSTORE = "C:/Users/Documents/itext/2/ks";
    public static final char[] PASSWORD = "password".toCharArray();
    public static final String SRC = "C:/Users/Documents/itext/2/unsigned1.pdf";
    public static final String DEST = "C:/Users/Documents/itext/2/unsigned1_signed.pdf";

    public void sign(String src, String dest,
            Certificate[] chain,
            PrivateKey pk, String digestAlgorithm, String provider,
            CryptoStandard subfilter,
            String reason, String location)
                    throws GeneralSecurityException, IOException, DocumentException {
        // Creating the reader and the stamper
        PdfReader reader = new PdfReader(src);
        FileOutputStream os = new FileOutputStream(dest);
        PdfStamper stamper = PdfStamper.createSignature(reader, os, '\0');
        // Creating the appearance
        PdfSignatureAppearance appearance = stamper.getSignatureAppearance();
        appearance.setReason(reason);
        appearance.setLocation(location);
        appearance.setVisibleSignature(new Rectangle(36, 748, 144, 780), 1, "sig");
        // Creating the signature
        ExternalDigest digest = new BouncyCastleDigest();
        ExternalSignature signature = new PrivateKeySignature(pk, digestAlgorithm, provider);
        MakeSignature.signDetached(appearance, digest, signature, chain, null, null, null, 0, subfilter);
    }

    public static void main(String[] args) throws GeneralSecurityException, IOException, DocumentException {
        BouncyCastleProvider provider = new BouncyCastleProvider();
        Security.addProvider(provider);
        KeyStore ks = KeyStore.getInstance(KeyStore.getDefaultType());
        ks.load(new FileInputStream(KEYSTORE), PASSWORD);
        String alias = (String)ks.aliases().nextElement();
        PrivateKey pk = (PrivateKey) ks.getKey(alias, PASSWORD);
        Certificate[] chain = ks.getCertificateChain(alias);
        C2_01_SignHelloWorld app = new C2_01_SignHelloWorld();
        app.sign(SRC, String.format(DEST, 1), chain, pk, DigestAlgorithms.SHA256, provider.getName(), CryptoStandard.CMS, "Test 1", "Ghent");
        app.sign(SRC, String.format(DEST, 2), chain, pk, DigestAlgorithms.SHA512, provider.getName(), CryptoStandard.CMS, "Test 2", "Ghent");
        app.sign(SRC, String.format(DEST, 3), chain, pk, DigestAlgorithms.SHA256, provider.getName(), CryptoStandard.CADES, "Test 3", "Ghent");
        app.sign(SRC, String.format(DEST, 4), chain, pk, DigestAlgorithms.RIPEMD160, provider.getName(), CryptoStandard.CADES, "Test 4", "Ghent");
    }
}

运行代码后，我收到此错误：

Exception in thread "main" java.lang.NoSuchMethodError: com.itextpdf.text.pdf.PdfSignatureAppearance.setCertificate(Ljava/security/cert/Certificate;)V
    at com.itextpdf.text.pdf.security.MakeSignature.signDetached(MakeSignature.java:115)
    at c2_01_signhelloworld.C2_01_SignHelloWorld.sign(C2_01_SignHelloWorld.java:59)
    at c2_01_signhelloworld.C2_01_SignHelloWorld.main(C2_01_SignHelloWorld.java:71)
Java Result: 1

此代码生成这两个文件，但是当我尝试打开unsigned1_signed.pdf时会出错...

Answer 1

这意味着您在项目中使用的库与系统库不同。

所以没有相同的方法。

Answer 2

仅使用iText 5.3.5修复此问题。较旧版本的iText库不适用于此代码。您可以检查pdfSignatureAppearance here

的itext 5.4.0快照

itext线程“main”java.lang.NoSuchMethodError中的异常

2 个答案: