http://www.bouncycastle.org/java.html: The Bouncy Castle Java APIs for CMS, PKCS, EAC, TSP, CMP, CRMF, OCSP, and certificate generation. This jar contains APIs for JDK 1.5 to JDK 1.8. The APIs can be used in conjunction with a JCE/JCA provider such as the one provided with the Bouncy Castle Cryptography APIs.
  • The Legion of the Bouncy Castle Inc. 
package org.bouncycastle.mime.smime;

import org.bouncycastle.mime.MimeParserContext;
import org.bouncycastle.operator.DigestCalculatorProvider;

public class SMimeParserContext
    implements MimeParserContext
{
    private final String defaultContentTransferEncoding;
    private final DigestCalculatorProvider digestCalculatorProvider;

    public SMimeParserContext(String defaultContentTransferEncoding, DigestCalculatorProvider digestCalculatorProvider)
    {
        this.defaultContentTransferEncoding = defaultContentTransferEncoding;
        this.digestCalculatorProvider = digestCalculatorProvider;
    }

    public String getDefaultContentTransferEncoding()
    {
        return defaultContentTransferEncoding;
    }

    public DigestCalculatorProvider getDigestCalculatorProvider()
    {
        return digestCalculatorProvider;
    }
}