Overview  Package   Class  Use  Deprecated  Index
Home >> All >> com >> lowagie >> bc >> [ asn1 overview ]	PREV CLASS  NEXT CLASS
SUMMARY:  JAVADOC |  SOURCE |  DOWNLOAD | NESTED | FIELD | CONSTR | METHOD	DETAIL: FIELD | CONSTR | METHOD

---

com.lowagie.bc.asn1
Class ASN1Null  

java.lang.Object
  com.lowagie.bc.asn1.DERObject
      com.lowagie.bc.asn1.ASN1Null

All Implemented Interfaces:

DEREncodable, DERTags

Direct Known Subclasses:

DERNull

---

public abstract class ASN1Null

extends DERObject

A NULL object.

---

Field Summary

 

Fields inherited from interface com.lowagie.bc.asn1.DERTags

APPLICATION, BIT_STRING, BMP_STRING, BOOLEAN, CONSTRUCTED, ENUMERATED, EXTERNAL, GENERAL_STRING, GENERALIZED_TIME, GRAPHIC_STRING, IA5_STRING, INTEGER, NULL, NUMERIC_STRING, OBJECT_IDENTIFIER, OCTET_STRING, PRINTABLE_STRING, SEQUENCE, SEQUENCE_OF, SET, SET_OF, T61_STRING, TAGGED, UNIVERSAL_STRING, UTC_TIME, UTF8_STRING, VIDEOTEX_STRING, VISIBLE_STRING

 

Constructor Summary

ASN1Null()

 

Method Summary
(package private) abstract  void	encode(DEROutputStream out)
boolean	equals(java.lang.Object o)           Determine whether this Object is semantically equal to another Object.
int	hashCode()           Get a value that represents this Object, as uniquely as possible within the confines of an int.

 

Methods inherited from class com.lowagie.bc.asn1.DERObject

getDERObject

 

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, toString, wait, wait, wait

 

Constructor Detail

ASN1Null

public ASN1Null()

Method Detail

hashCode

public int hashCode()

Description copied from class: java.lang.Object

Get a value that represents this Object, as uniquely as possible within the confines of an int.

There are some requirements on this method which subclasses must follow:

• Semantic equality implies identical hashcodes. In other words, if a.equals(b) is true, then a.hashCode() == b.hashCode() must be as well. However, the reverse is not necessarily true, and two objects may have the same hashcode without being equal.
• It must be consistent. Whichever value o.hashCode() returns on the first invocation must be the value returned on all later invocations as long as the object exists. Notice, however, that the result of hashCode may change between separate executions of a Virtual Machine, because it is not invoked on the same object.

Notice that since hashCode is used in java.util.Hashtable and other hashing classes, a poor implementation will degrade the performance of hashing (so don't blindly implement it as returning a constant!). Also, if calculating the hash is time-consuming, a class may consider caching the results.

The default implementation returns System.identityHashCode(this)

---

equals

public boolean equals(java.lang.Object o)

Description copied from class: java.lang.Object

Determine whether this Object is semantically equal to another Object.

There are some fairly strict requirements on this method which subclasses must follow:

• It must be transitive. If a.equals(b) and b.equals(c), then a.equals(c) must be true as well.
• It must be symmetric. a.equals(b) and b.equals(a) must have the same value.
• It must be reflexive. a.equals(a) must always be true.
• It must be consistent. Whichever value a.equals(b) returns on the first invocation must be the value returned on all later invocations.
• a.equals(null) must be false.
• It must be consistent with hashCode(). That is, a.equals(b) must imply a.hashCode() == b.hashCode(). The reverse is not true; two objects that are not equal may have the same hashcode, but that has the potential to harm hashing performance.

This is typically overridden to throw a java.lang.ClassCastException if the argument is not comparable to the class performing the comparison, but that is not a requirement. It is legal for a.equals(b) to be true even though a.getClass() != b.getClass(). Also, it is typical to never cause a java.lang.NullPointerException.

In general, the Collections API (java.util) use the equals method rather than the == operator to compare objects. However, java.util.IdentityHashMap is an exception to this rule, for its own good reasons.

The default implementation returns this == o.

---

encode

abstract void encode(DEROutputStream out)
              throws java.io.IOException

Specified by:

encode in class DERObject

---

Overview  Package   Class  Use  Deprecated  Index
Home >> All >> com >> lowagie >> bc >> [ asn1 overview ]	PREV CLASS  NEXT CLASS
SUMMARY:  JAVADOC |  SOURCE |  DOWNLOAD | NESTED | FIELD | CONSTR | METHOD	DETAIL: FIELD | CONSTR | METHOD

---