This constructor will not modify environment or save a reference to it, but may save a clone.
If attribute does not exist,
create the attribute. The resulting attribute has a union of the
specified value set and the prior value set.
Adding an attribute with no value will throw
InvalidAttributeValueException
if the attribute must have
at least one value. For a single-valued attribute where that attribute
already exists, throws AttributeInUseException
.
If attempting to add more than one value to a single-valued attribute,
throws InvalidAttributeValueException
.
The value of this constant is 1.
The resulting attribute has the set difference of its prior value set and the specified value set. If no values are specified, deletes the entire attribute. If the attribute does not exist, or if some or all members of the specified value set do not exist, this absence may be ignored and the operation succeeds, or a NamingException may be thrown to indicate the absence. Removal of the last value will remove the attribute if the attribute is required to have at least one value.
The value of this constant is 3.
If attribute already exists,
replaces all existing values with new specified values. If the
attribute does not exist, creates it. If no value is specified,
deletes all the values of the attribute.
Removal of the last value will remove the attribute if the attribute
is required to have at least one value. If
attempting to add more than one value to a single-valued attribute,
throws InvalidAttributeValueException
.
The value of this constant is 2.
The equals
method implements an equivalence relation
on non-null object references:
x
, x.equals(x)
should return
true
.
x
and y
, x.equals(y)
should return true
if and only if
y.equals(x)
returns true
.
x
, y
, and z
, if
x.equals(y)
returns true
and
y.equals(z)
returns true
, then
x.equals(z)
should return true
.
x
and y
, multiple invocations of
x.equals(y) consistently return true
or consistently return false
, provided no
information used in equals
comparisons on the
objects is modified.
x
,
x.equals(null)
should return false
.
The equals method for class Object
implements
the most discriminating possible equivalence relation on objects;
that is, for any non-null reference values x
and
y
, this method returns true
if and only
if x
and y
refer to the same object
(x == y
has the value true
).
Note that it is generally necessary to override the hashCode method whenever this method is overridden, so as to maintain the general contract for the hashCode method, which states that equal objects must have equal hash codes.
If the object does not have an attribute specified, the directory will ignore the nonexistent attribute and return those requested attributes that the object does have.
A directory might return more attributes than was requested (see Attribute Type Names in the class description), but is not allowed to return arbitrary, unrelated attributes.
See also Operational Attributes in the class description.
This method returns the root of the schema information tree that is applicable to the named object. Several named objects (or even an entire directory) might share the same schema.
Issues such as structure and contents of the schema tree, permission to modify to the contents of the schema tree, and the effect of such modifications on the directory are dependent on the underlying directory.
One category of information found in directory schemas is class definitions. An "object class" definition specifies the object's type and what attributes (mandatory and optional) the object must/can have. Note that the term "object class" being referred to here is in the directory sense rather than in the Java sense. For example, if the named object is a directory object of "Person" class, getSchemaClassDefinition() would return a DirContext representing the (directory's) object class definition of "Person".
The information that can be retrieved from an object class definition is directory-dependent.
Prior to JNDI 1.2, this method returned a single schema object representing the class definition of the named object. Since JNDI 1.2, this method returns a DirContext containing all of the named object's class definitions.
java.util.Hashtable
.
The general contract of hashCode
is:
hashCode
method on each of
the two objects must produce the same integer result.
As much as is reasonably practical, the hashCode method defined by class Object does return distinct integers for distinct objects. (This is typically implemented by converting the internal address of the object into an integer, but this implementation technique is not required by the JavaTM programming language.)
wait
methods.
The awakened thread will not be able to proceed until the current thread relinquishes the lock on this object. The awakened thread will compete in the usual manner with any other threads that might be actively competing to synchronize on this object; for example, the awakened thread enjoys no reliable privilege or disadvantage in being the next thread to lock this object.
This method should only be called by a thread that is the owner of this object's monitor. A thread becomes the owner of the object's monitor in one of three ways:
synchronized
statement
that synchronizes on the object.
Class,
by executing a
synchronized static method of that class.
Only one thread at a time can own an object's monitor.
wait
methods.
The awakened threads will not be able to proceed until the current thread relinquishes the lock on this object. The awakened threads will compete in the usual manner with any other threads that might be actively competing to synchronize on this object; for example, the awakened threads enjoy no reliable privilege or disadvantage in being the next thread to lock this object.
This method should only be called by a thread that is the owner
of this object's monitor. See the notify
method for a
description of the ways in which a thread can become the owner of
a monitor.
SearchControls
settings.
For an object to be selected, each attribute in
matchingAttributes
must match some attribute of the
object. If matchingAttributes
is empty or
null, all objects in the target context are returned.
An attribute A1 in
matchingAttributes
is considered to match an
attribute A2 of an object if
A1 and A2 have the same
identifier, and each value of A1 is equal
to some value of A2. This implies that the
order of values is not significant, and that
A2 may contain "extra" values not found in
A1 without affecting the comparison. It
also implies that if A1 has no values, then
testing for a match is equivalent to testing for the presence
of an attribute A2 with the same
identifier.
The precise definition of "equality" used in comparing attribute values
is defined by the underlying directory service. It might use the
Object.equals
method, for example, or might use a schema
to specify a different equality operation.
For matching based on operations other than equality (such as
substring comparison) use the version of the search
method that takes a filter argument.
When changes are made to this DirContext, the effect on enumerations returned by prior calls to this method is undefined.
If the object does not have the attribute specified, the directory will ignore the nonexistent attribute and return the requested attributes that the object does have.
A directory might return more attributes than was requested (see Attribute Type Names in the class description), but is not allowed to return arbitrary, unrelated attributes.
See also Operational Attributes in the class description.
The interpretation of filterExpr
is based on RFC
2254. It may additionally contain variables of the form
{i}
-- where i
is an integer -- that
refer to objects in the filterArgs
array. The
interpretation of filterExpr
is otherwise
identical to that of the filter
parameter of the
method search(Name, String, SearchControls)
.
When a variable {i}
appears in a search filter, it
indicates that the filter argument filterArgs[i]
is to be used in that place. Such variables may be used
wherever an attr, value, or
matchingrule production appears in the filter grammar
of RFC 2254, section 4. When a string-valued filter argument
is substituted for a variable, the filter is interpreted as if
the string were given in place of the variable, with any
characters having special significance within filters (such as
'*'
) having been escaped according to the rules of
RFC 2254.
For directories that do not use a string representation for some or all of their attributes, the filter argument corresponding to an attribute value may be of a type other than String. Directories that support unstructured binary-valued attributes, for example, should accept byte arrays as filter arguments. The interpretation (if any) of filter arguments of any other type is determined by the service provider for that directory, which maps the filter operations onto operations with corresponding semantics in the underlying directory.
This method returns an enumeration of the results.
Each element in the enumeration contains the name of the object
and other information about the object (see SearchResult
).
The name is either relative to the target context of the search
(which is named by the name
parameter), or
it is a URL string. If the target context is included in
the enumeration (as is possible when
cons
specifies a search scope of
SearchControls.OBJECT_SCOPE
or
SearchControls.SUBSTREE_SCOPE
),
its name is the empty string.
The SearchResult may also contain attributes of the matching object if the cons argument specifies that attributes be returned.
If the object does not have a requested attribute, that nonexistent attribute will be ignored. Those requested attributes that the object does have will be returned.
A directory might return more attributes than were requested (see Attribute Type Names in the class description) but is not allowed to return arbitrary, unrelated attributes.
If a search filter with invalid variable substitutions is provided to this method, the result is undefined. When changes are made to this DirContext, the effect on enumerations returned by prior calls to this method is undefined.
See also Operational Attributes in the class description.
The format and interpretation of filter
follows RFC 2254
with the
following interpretations for attr
and value
mentioned in the RFC.
attr
is the attribute's identifier.
value
is the string representation the attribute's value.
The translation of this string representation into the attribute's value
is directory-specific.
For the assertion "someCount=127", for example, attr
is "someCount" and value
is "127".
The provider determines, based on the attribute ID ("someCount")
(and possibly its schema), that the attribute's value is an integer.
It then parses the string "127" appropriately.
Any non-ASCII characters in the filter string should be represented by the appropriate Java (Unicode) characters, and not encoded as UTF-8 octets. Alternately, the "backslash-hexcode" notation described in RFC 2254 may be used.
If the directory does not support a string representation of
some or all of its attributes, the form of search
that
accepts filter arguments in the form of Objects can be used instead.
The service provider for such a directory would then translate
the filter arguments to its service-specific representation
for filter evaluation.
See search(Name, String, Object[], SearchControls)
.
RFC 2254 defines certain operators for the filter, including substring matches, equality, approximate match, greater than, less than. These operators are mapped to operators with corresponding semantics in the underlying directory. For example, for the equals operator, suppose the directory has a matching rule defining "equality" of the attributes in the filter. This rule would be used for checking equality of the attributes specified in the filter with the attributes of objects in the directory. Similarly, if the directory has a matching rule for ordering, this rule would be used for making "greater than" and "less than" comparisons.
Not all of the operators defined in RFC 2254 are applicable to all
attributes. When an operator is not applicable, the exception
InvalidSearchFilterException
is thrown.
The result is returned in an enumeration of SearchResults.
Each SearchResult contains the name of the object
and other information about the object (see SearchResult).
The name is either relative to the target context of the search
(which is named by the name
parameter), or
it is a URL string. If the target context is included in
the enumeration (as is possible when
cons
specifies a search scope of
SearchControls.OBJECT_SCOPE
or
SearchControls.SUBSTREE_SCOPE
), its name is the empty
string. The SearchResult may also contain attributes of the
matching object if the cons argument specified that attributes
be returned.
If the object does not have a requested attribute, that nonexistent attribute will be ignored. Those requested attributes that the object does have will be returned.
A directory might return more attributes than were requested (see Attribute Type Names in the class description) but is not allowed to return arbitrary, unrelated attributes.
See also Operational Attributes in the class description.
toString
method returns a string that
"textually represents" this object. The result should
be a concise but informative representation that is easy for a
person to read.
It is recommended that all subclasses override this method.
The toString
method for class Object
returns a string consisting of the name of the class of which the
object is an instance, the at-sign character `@
', and
the unsigned hexadecimal representation of the hash code of the
object. In other words, this method returns a string equal to the
value of:
getClass().getName() + '@' + Integer.toHexString(hashCode())
The current thread must own this object's monitor. The thread
releases ownership of this monitor and waits until another thread
notifies threads waiting on this object's monitor to wake up
either through a call to the notify
method or the
notifyAll
method. The thread then waits until it can
re-obtain ownership of the monitor and resumes execution.
As in the one argument version, interrupts and spurious wakeups are possible, and this method should always be used in a loop:
synchronized (obj) { while (<condition does not hold>) obj.wait(); ... // Perform action appropriate to condition }This method should only be called by a thread that is the owner of this object's monitor. See the
notify
method for a
description of the ways in which a thread can become the owner of
a monitor.The current thread must own this object's monitor.
This method causes the current thread (call it T) to place itself in the wait set for this object and then to relinquish any and all synchronization claims on this object. Thread T becomes disabled for thread scheduling purposes and lies dormant until one of four things happens:
A thread can also wake up without being notified, interrupted, or timing out, a so-called spurious wakeup. While this will rarely occur in practice, applications must guard against it by testing for the condition that should have caused the thread to be awakened, and continuing to wait if the condition is not satisfied. In other words, waits should always occur in loops, like this one:
synchronized (obj) { while (<condition does not hold>) obj.wait(timeout); ... // Perform action appropriate to condition }(For more information on this topic, see Section 3.2.3 in Doug Lea's "Concurrent Programming in Java (Second Edition)" (Addison-Wesley, 2000), or Item 50 in Joshua Bloch's "Effective Java Programming Language Guide" (Addison-Wesley, 2001).
If the current thread is interrupted by another thread while it is waiting, then an InterruptedException is thrown. This exception is not thrown until the lock status of this object has been restored as described above.
Note that the wait method, as it places the current thread into the wait set for this object, unlocks only this object; any other objects on which the current thread may be synchronized remain locked while the thread waits.
This method should only be called by a thread that is the owner
of this object's monitor. See the notify
method for a
description of the ways in which a thread can become the owner of
a monitor.
This method is similar to the wait
method of one
argument, but it allows finer control over the amount of time to
wait for a notification before giving up. The amount of real time,
measured in nanoseconds, is given by:
1000000*timeout+nanos
In all other respects, this method does the same thing as the method of one argument. In particular, wait(0, 0) means the same thing as wait(0).
The current thread must own this object's monitor. The thread releases ownership of this monitor and waits until either of the following two conditions has occurred:
notify
method
or the notifyAll
method.
timeout
milliseconds plus nanos
nanoseconds arguments, has
elapsed.
The thread then waits until it can re-obtain ownership of the monitor and resumes execution.
As in the one argument version, interrupts and spurious wakeups are possible, and this method should always be used in a loop:
synchronized (obj) { while (<condition does not hold>) obj.wait(timeout, nanos); ... // Perform action appropriate to condition }This method should only be called by a thread that is the owner of this object's monitor. See the
notify
method for a
description of the ways in which a thread can become the owner of
a monitor.