如何用Java以最快的方式签署XML

Question

需要一些关于(优化(以及如何以最快的方式使用证书对XML进行签名的提示/建议。在某些数据库(Oracle(上，对文件进行签名需要30毫秒。。但在另一个数据库上，它需要1.2秒。这个函数/方法是在循环中调用的。它对一些XML数据进行签名，并在字符串中返回一个签名的XML。(Java方法公开为PL/SQL函数(。

public static String signXML(String vhodniXml) throws Exception {
DocumentBuilderFactory dbFactory = DocumentBuilderFactory.newInstance();
dbFactory.setNamespaceAware(true);
Document doc =  dbFactory.newDocumentBuilder().parse(new ByteArrayInputStream(vhodniXml.getBytes()));
NodeList nl = doc.getElementsByTagName("fu:BusinessPremiseRequest");
Node node = nl.item(0);
((Element) node).setIdAttribute("Id", true);
Enumeration e = p12.aliases();
String alias = (String) e.nextElement();
Key privateKey = p12.getKey(alias, geslo.toCharArray());
KeyStore.PrivateKeyEntry keyEntry
= (KeyStore.PrivateKeyEntry) p12.getEntry(alias, new KeyStore.PasswordProtection(geslo.toCharArray()));
X509Certificate cert = (X509Certificate) keyEntry.getCertificate();
PublicKey publicKey = cert.getPublicKey();
final XMLSignatureFactory sigFactory = XMLSignatureFactory.getInstance("DOM");
// Create a Reference to the enveloped document
Reference ref = sigFactory.newReference("#data",
sigFactory.newDigestMethod(DigestMethod.SHA256, null),
Collections.singletonList(sigFactory.newTransform(Transform.ENVELOPED, (TransformParameterSpec) null)),
null,
null);
SignedInfo si = sigFactory.newSignedInfo(sigFactory.newCanonicalizationMethod(CanonicalizationMethod.INCLUSIVE, (C14NMethodParameterSpec) null), sigFactory.newSignatureMethod("http://www.w3.org/2001/04/xmldsig-more#rsa-sha256", null), Collections.singletonList(ref));
// Create a KeyValue containing the RSA PublicKey
KeyInfoFactory keyInfoFactory = sigFactory.getKeyInfoFactory();
X509IssuerSerial x509IssuerSerial = keyInfoFactory.newX509IssuerSerial(cert.getSubjectX500Principal().getName(), cert.getSerialNumber());
List x509Content = new ArrayList();
x509Content.add(cert.getSubjectX500Principal().getName());
x509Content.add(x509IssuerSerial);
KeyValue keyValue = keyInfoFactory.newKeyValue(publicKey);
X509Data xd = keyInfoFactory.newX509Data(x509Content);
// Create a KeyInfo and add the KeyValue to it
KeyInfo keyInfo = keyInfoFactory.newKeyInfo(Collections.singletonList(xd));
// Create a DOMSignContext and specify the RSA PrivateKey and
// location of the resulting XMLSignature's parent element
DOMSignContext dsc = new DOMSignContext(
privateKey,
node
);
// Create the XMLSignature (but don't sign it yet)
XMLSignature signature = sigFactory.newXMLSignature(si, keyInfo);
// Marshal, generate (and sign) the enveloped signature
signature.sign(dsc);
ByteArrayOutputStream os = new ByteArrayOutputStream();
Transformer trans = TransformerFactory.newInstance()
.newTransformer();
trans.transform(new DOMSource(doc), new StreamResult(os));
return new String(os.toByteArray());
}

Answer 1

首先要做的是通过将与键相关的对象存储在字段中来删除一些IO操作，因为读取KeyStore以获取键需要时间。