如何使用Java中的bouncyCastle向证书添加PrivateKeyUsage扩展？

我有一个X509证书，我要向其添加扩展...我想添加PrivateKeyUsage扩展，但我不知道如何创建PrivateKeyUsage对象，也不知道如何为其赋值Not BeeBead；Not After值(&；Not After值)...谢谢

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解决方案

Date from = new Date();
Date to = new Date(System.currentTimeMillis()+ 30*1000*60*60l);

ASN1EncodableVector v = new ASN1EncodableVector();
DERGeneralizedTime fromTime = new DERGeneralizedTime(from);    
v.add(new DERTaggedObject(false, 0, fromTime));

DERGeneralizedTime toTime = new DERGeneralizedTime(to);    
v.add(new DERTaggedObject(false, 1, toTime));

DERObject o = new DERSequence(v);    
PrivateKeyUsagePeriod pkup = PrivateKeyUsagePeriod.getInstance(o);    
v3CertGen.addExtension(x509Extensions.PrivateKeyUsagePeriod, false, pkup);