iaik.asn1
Class UTCTime

java.lang.Object
  |
  +--iaik.asn1.ASN1Object
        |
        +--iaik.asn1.UTCTime

All Implemented Interfaces:

Cloneable

public class UTCTime

extends ASN1Object

This class implements the native ASN.1 type "UTCTime".

UTCTime is a simple useful ASN.1 string type identified by the UNIVERSAL TAG number 23.

An ASN.1 UTCTime object may represent any coordinated universal time or Greenwich Mean Time (GMT) value. An UTCTime value specifies the calendar date (year, month, day: YYMMDD), the time value (hours, minutes and optionally seconds: hhmmss) and the time zone respectively time-shift: Z denotes that the local time corresponds to GMT, a time-shift is indicated by +/- <time value>.

For instance: local time is GMT and represents the twelfth November 1997 at 15:30:10p.m:

 UTCTime utcTime = new UTCTime("971112153010Z");
 

Supposing a time-shift of two hours making the lokal time ahead from GMT, we may write:

 UTCTime utcTime = new UTCTime("971112173010+0200");
 

Conforming systems shall interpret the year field (YY) as follows:

• Where YY is greater than 50, the year shall be interpreted as 19YY; and
• Where YY is less than or equal to 50, the year shall be interpreted as 20YY.

For higher precision use GeneralizedTime.

When calling the getValue method for getting the inherent value from an ASN.1 UTCTime instance, a Java object of type String is returned:

 String timeStr = (String)utcTime.getValue();
 

DER en/decoding generally is done by means of the several methods of the DerCoder class; decoding alternatively may be performed by using the DerInputStream utility.

Version:

File Revision 17

See Also:

ASN1Object, ASN, GeneralizedTime

Fields inherited from class iaik.asn1.ASN1Object

asnType, constructed, encode_listener, indefinite_length, isStringType, stream_mode

Constructor Summary

protected	UTCTime() Creates an empty object.
	UTCTime(String value) Creates a new ASN.1 UTCTime object for the given Java String value.

Method Summary

protected void	decode(int length, InputStream is) Decodes a UTCTime value from the given InputStream.
protected void	encode(OutputStream os) DER encodes this UTCTime ASN1Object and writes the result to the given output stream.
Object	getValue() Returns the value of this UTCTime as a String.
void	setValue(Object object) Sets the value of this UTCTime.
String	toString() Returns a string that represents the contents of this UTCTime ASN1Object.

Methods inherited from class iaik.asn1.ASN1Object

addComponent, addEncodeListener, clone, countComponents, encodeObject, getAsnType, getComponentAt, indefiniteLength, isA, isConstructed, isStringType, setIndefiniteLength

Methods inherited from class java.lang.Object

equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

UTCTime

protected UTCTime()

Creates an empty object.

UTCTime

public UTCTime(String value)

Creates a new ASN.1 UTCTime object for the given Java String value.

Parameters:

value - the String value this UTCTime object should be initialized with

Method Detail

getValue

public Object getValue()

Returns the value of this UTCTime as a String.

Overrides:

getValue in class ASN1Object

Returns:

the value of this UTCTime as a String object

setValue

public void setValue(Object object)

Sets the value of this UTCTime. The supplied value has to be a Java object of type String.

Overrides:

setValue in class ASN1Object

Parameters:

value - the String value this UTCTime object shall represent

encode

protected void encode(OutputStream os)
               throws IOException

DER encodes this UTCTime ASN1Object and writes the result to the given output stream. This is a protected method and will not be used by an application for DER encoding a UTCTime object. An application will call one of the encode methods of the DerCoder class for performing the encoding, and the DerCoder internally will call this encode method.

Overrides:

encode in class ASN1Object

Parameters:

os - the output stream to which to write the data

Throws:

IOException - if an I/O error occurs while writing to the stream

decode

protected void decode(int length,
                      InputStream is)
               throws IOException

Decodes a UTCTime value from the given InputStream. The given input stream carries DER encoded data, and the next length bytes to be read represent the value of an ASN.1 object of type UTCTime.

This is a protected method and will not be used by an application for decoding a DER encoded UTCTime. An application will call one of the decode methods of the DerCoder class for performing the decoding. The DerCoder then determines the number of bytes (length) occupied by the value of this UTCTime object and internally calls this decode method for actually reading the value.

Overrides:

decode in class ASN1Object

Parameters:

length - the already decoded length, i.e. number of the bytes representing the value of the GeneralizedTime to be decoded

is - the input stream from which the DER encoded data is read in

Throws:

IOException - if there is a problem with the InputStream

toString

public String toString()

Returns a string that represents the contents of this UTCTime ASN1Object.

Overrides:

toString in class ASN1Object

Returns:

the string representation

See Also:

ASN1Object.toString()