Java tutorial
package org.bouncycastle.asn1.cms; import java.text.ParseException; import java.text.SimpleDateFormat; import java.util.Date; import java.util.Locale; import java.util.SimpleTimeZone; import org.bouncycastle.asn1.ASN1Choice; import org.bouncycastle.asn1.ASN1GeneralizedTime; import org.bouncycastle.asn1.ASN1Object; import org.bouncycastle.asn1.ASN1Primitive; import org.bouncycastle.asn1.ASN1TaggedObject; import org.bouncycastle.asn1.ASN1UTCTime; import org.bouncycastle.asn1.DERGeneralizedTime; import org.bouncycastle.asn1.DERUTCTime; /** * <a href="http://tools.ietf.org/html/rfc5652#section-11.3">RFC 5652</a>: * Dual-mode timestamp format producing either UTCTIme or GeneralizedTime. * <p> * <pre> * Time ::= CHOICE { * utcTime UTCTime, * generalTime GeneralizedTime } * </pre> * <p> * This has a constructor using java.util.Date for input which generates * a {@link org.bouncycastle.asn1.DERUTCTime DERUTCTime} object if the * supplied datetime is in range 1950-01-01-00:00:00 UTC until 2049-12-31-23:59:60 UTC. * If the datetime value is outside that range, the generated object will be * {@link org.bouncycastle.asn1.DERGeneralizedTime DERGeneralizedTime}. */ public class Time extends ASN1Object implements ASN1Choice { ASN1Primitive time; public static Time getInstance(ASN1TaggedObject obj, boolean explicit) { return getInstance(obj.getObject()); } /** * @deprecated use getInstance() */ public Time(ASN1Primitive time) { if (!(time instanceof ASN1UTCTime) && !(time instanceof ASN1GeneralizedTime)) { throw new IllegalArgumentException("unknown object passed to Time"); } this.time = time; } /** * Creates a time object from a given date - if the date is between 1950 * and 2049 a UTCTime object is generated, otherwise a GeneralizedTime * is used. * * @param time a date object representing the time of interest. */ public Time(Date time) { SimpleTimeZone tz = new SimpleTimeZone(0, "Z"); SimpleDateFormat dateF = new SimpleDateFormat("yyyyMMddHHmmss"); dateF.setTimeZone(tz); String d = dateF.format(time) + "Z"; int year = Integer.parseInt(d.substring(0, 4)); if (year < 1950 || year > 2049) { this.time = new DERGeneralizedTime(d); } else { this.time = new DERUTCTime(d.substring(2)); } } /** * Creates a time object from a given date and locale - if the date is between 1950 * and 2049 a UTCTime object is generated, otherwise a GeneralizedTime * is used. You may need to use this constructor if the default locale * doesn't use a Gregorian calender so that the GeneralizedTime produced is compatible with other ASN.1 implementations. * * @param time a date object representing the time of interest. * @param locale an appropriate Locale for producing an ASN.1 GeneralizedTime value. */ public Time(Date time, Locale locale) { SimpleTimeZone tz = new SimpleTimeZone(0, "Z"); SimpleDateFormat dateF = new SimpleDateFormat("yyyyMMddHHmmss", locale); dateF.setTimeZone(tz); String d = dateF.format(time) + "Z"; int year = Integer.parseInt(d.substring(0, 4)); if (year < 1950 || year > 2049) { this.time = new DERGeneralizedTime(d); } else { this.time = new DERUTCTime(d.substring(2)); } } /** * Return a Time object from the given object. * <p> * Accepted inputs: * <ul> * <li> null → null * <li> {@link Time} object * <li> {@link org.bouncycastle.asn1.DERUTCTime DERUTCTime} object * <li> {@link org.bouncycastle.asn1.DERGeneralizedTime DERGeneralizedTime} object * </ul> * * @param obj the object we want converted. * @exception IllegalArgumentException if the object cannot be converted. */ public static Time getInstance(Object obj) { if (obj == null || obj instanceof Time) { return (Time) obj; } else if (obj instanceof ASN1UTCTime) { return new Time((ASN1UTCTime) obj); } else if (obj instanceof ASN1GeneralizedTime) { return new Time((ASN1GeneralizedTime) obj); } throw new IllegalArgumentException("unknown object in factory: " + obj.getClass().getName()); } /** * Get the date+tine as a String in full form century format. */ public String getTime() { if (time instanceof ASN1UTCTime) { return ((ASN1UTCTime) time).getAdjustedTime(); } else { return ((ASN1GeneralizedTime) time).getTime(); } } /** * Get java.util.Date version of date+time. */ public Date getDate() { try { if (time instanceof ASN1UTCTime) { return ((ASN1UTCTime) time).getAdjustedDate(); } else { return ((ASN1GeneralizedTime) time).getDate(); } } catch (ParseException e) { // this should never happen throw new IllegalStateException("invalid date string: " + e.getMessage()); } } /** * Produce an object suitable for an ASN1OutputStream. */ public ASN1Primitive toASN1Primitive() { return time; } }