Java tutorial
package org.bouncycastle.cert.jcajce; import java.io.ByteArrayInputStream; import java.io.IOException; import java.security.NoSuchProviderException; import java.security.Provider; import java.security.cert.CRLException; import java.security.cert.CertificateException; import java.security.cert.CertificateFactory; import java.security.cert.X509CRL; import org.bouncycastle.cert.X509CRLHolder; /** * Class for converting an X509CRLHolder into a corresponding X509CRL object tied to a * particular JCA provider. */ public class JcaX509CRLConverter { private CertHelper helper = new DefaultCertHelper(); /** * Base constructor, configure with the default provider. */ public JcaX509CRLConverter() { this.helper = new DefaultCertHelper(); } /** * Set the provider to use from a Provider object. * * @param provider the provider to use. * @return the converter instance. */ public JcaX509CRLConverter setProvider(Provider provider) { this.helper = new ProviderCertHelper(provider); return this; } /** * Set the provider to use by name. * * @param providerName name of the provider to use. * @return the converter instance. */ public JcaX509CRLConverter setProvider(String providerName) { this.helper = new NamedCertHelper(providerName); return this; } /** * Use the configured converter to produce a X509CRL object from a X509CRLHolder object. * * @param crlHolder the holder to be converted * @return a X509CRL object * @throws CRLException if the conversion is unable to be made. */ public X509CRL getCRL(X509CRLHolder crlHolder) throws CRLException { try { CertificateFactory cFact = helper.getCertificateFactory("X.509"); return (X509CRL) cFact.generateCRL(new ByteArrayInputStream(crlHolder.getEncoded())); } catch (IOException e) { throw new ExCRLException("exception parsing certificate: " + e.getMessage(), e); } catch (NoSuchProviderException e) { throw new ExCRLException("cannot find required provider:" + e.getMessage(), e); } catch (CertificateException e) { throw new ExCRLException("cannot create factory: " + e.getMessage(), e); } } private class ExCRLException extends CRLException { private Throwable cause; public ExCRLException(String msg, Throwable cause) { super(msg); this.cause = cause; } public Throwable getCause() { return cause; } } }