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javax.naming.directory
public interface: DirContext [javadoc | source]

All Implemented Interfaces:
    Context

All Known Implementing Classes:
    InitialLdapContext, InitialDirContext, LdapContext, EventDirContext, ContinuationDirContext

The directory service interface, containing methods for examining and updating attributes associated with objects, and for searching the directory.

Names

Each name passed as an argument to a DirContext method is relative to that context. The empty name is used to name the context itself. The name parameter may never be null.

Most of the methods have overloaded versions with one taking a Name parameter and one taking a String. These overloaded versions are equivalent in that if the Name and String parameters are just different representations of the same name, then the overloaded versions of the same methods behave the same. In the method descriptions below, only one version is documented. The second version instead has a link to the first: the same documentation applies to both.

See Context for a discussion on the interpretation of the name argument to the Context methods. These same rules apply to the name argument to the DirContext methods.

Attribute Models

There are two basic models of what attributes should be associated with. First, attributes may be directly associated with a DirContext object. In this model, an attribute operation on the named object is roughly equivalent to a lookup on the name (which returns the DirContext object), followed by the attribute operation invoked on the DirContext object in which the caller supplies an empty name. The attributes can be viewed as being stored along with the object (note that this does not imply that the implementation must do so).

The second model is that attributes are associated with a name (typically an atomic name) in a DirContext. In this model, an attribute operation on the named object is roughly equivalent to a lookup on the name of the parent DirContext of the named object, followed by the attribute operation invoked on the parent in which the caller supplies the terminal atomic name. The attributes can be viewed as being stored in the parent DirContext (again, this does not imply that the implementation must do so). Objects that are not DirContexts can have attributes, as long as their parents are DirContexts.

JNDI support both of these models. It is up to the individual service providers to decide where to "store" attributes. JNDI clients are safest when they do not make assumptions about whether an object's attributes are stored as part of the object, or stored within the parent object and associated with the object's name.

Attribute Type Names

In the getAttributes() and search() methods, you can supply the attributes to return by supplying a list of attribute names (strings). The attributes that you get back might not have the same names as the attribute names you have specified. This is because some directories support features that cause them to return other attributes. Such features include attribute subclassing, attribute name synonyms, and attribute language codes.

In attribute subclassing, attributes are defined in a class hierarchy. In some directories, for example, the "name" attribute might be the superclass of all name-related attributes, including "commonName" and "surName". Asking for the "name" attribute might return both the "commonName" and "surName" attributes.

With attribute type synonyms, a directory can assign multiple names to the same attribute. For example, "cn" and "commonName" might both refer to the same attribute. Asking for "cn" might return the "commonName" attribute.

Some directories support the language codes for attributes. Asking such a directory for the "description" attribute, for example, might return all of the following attributes:

Operational Attributes

Some directories have the notion of "operational attributes" which are attributes associated with a directory object for administrative purposes. An example of operational attributes is the access control list for an object.

In the getAttributes() and search() methods, you can specify that all attributes associated with the requested objects be returned by supply null as the list of attributes to return. The attributes returned do not include operational attributes. In order to retrieve operational attributes, you must name them explicitly.

Named Context

There are certain methods in which the name must resolve to a context (for example, when searching a single level context). The documentation of such methods use the term named context to describe their name parameter. For these methods, if the named object is not a DirContext, NotContextException is thrown. Aside from these methods, there is no requirement that the named object be a DirContext.

Parameters

An Attributes, SearchControls, or array object passed as a parameter to any method will not be modified by the service provider. The service provider may keep a reference to it for the duration of the operation, including any enumeration of the method's results and the processing of any referrals generated. The caller should not modify the object during this time. An Attributes object returned by any method is owned by the caller. The caller may subsequently modify it; the service provider will not.

Exceptions

All the methods in this interface can throw a NamingException or any of its subclasses. See NamingException and their subclasses for details on each exception.

Field Summary
public static final  int ADD_ATTRIBUTE    This constant specifies to add an attribute with the specified values.

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.

 
public static final  int REPLACE_ATTRIBUTE    This constant specifies to replace an attribute with specified values.

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.

 
public static final  int REMOVE_ATTRIBUTE    This constant specifies to delete the specified attribute values from the attribute.

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.

 
Method from javax.naming.directory.DirContext Summary:
bind,   bind,   createSubcontext,   createSubcontext,   getAttributes,   getAttributes,   getAttributes,   getAttributes,   getSchema,   getSchema,   getSchemaClassDefinition,   getSchemaClassDefinition,   modifyAttributes,   modifyAttributes,   modifyAttributes,   modifyAttributes,   rebind,   rebind,   search,   search,   search,   search,   search,   search,   search,   search
Method from javax.naming.directory.DirContext Detail:
 public  void bind(Name name,
    Object obj,
    Attributes attrs) throws NamingException
    Binds a name to an object, along with associated attributes.
If attrs is null, the resulting binding will have
the attributes associated with obj if obj is a
DirContext, and no attributes otherwise.
If attrs is non-null, the resulting binding will have
attrs as its attributes; any attributes associated with
obj are ignored.
 public  void bind(String name,
    Object obj,
    Attributes attrs) throws NamingException
 public DirContext createSubcontext(Name name,
    Attributes attrs) throws NamingException
    Creates and binds a new context, along with associated attributes.
This method creates a new subcontext with the given name, binds it in
the target context (that named by all but terminal atomic
component of the name), and associates the supplied attributes
with the newly created object.
All intermediate and target contexts must already exist.
If attrs is null, this method is equivalent to
Context.createSubcontext().
 public DirContext createSubcontext(String name,
    Attributes attrs) throws NamingException
 public Attributes getAttributes(Name name) throws NamingException
    Retrieves all of the attributes associated with a named object.
See the class description regarding attribute models, attribute
type names, and operational attributes.
 public Attributes getAttributes(String name) throws NamingException
    Retrieves all of the attributes associated with a named object.
See #getAttributes(Name)  for details.
 public Attributes getAttributes(Name name,
    String[] attrIds) throws NamingException
    Retrieves selected attributes associated with a named object.
See the class description regarding attribute models, attribute
type names, and operational attributes.


     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.
 public Attributes getAttributes(String name,
    String[] attrIds) throws NamingException
 public DirContext getSchema(Name name) throws NamingException
    Retrieves the schema associated with the named object.
The schema describes rules regarding the structure of the namespace
and the attributes stored within it.  The schema
specifies what types of objects can be added to the directory and where
they can be added; what mandatory and optional attributes an object
can have. The range of support for schemas is directory-specific.


     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.
 public DirContext getSchema(String name) throws NamingException
    Retrieves the schema associated with the named object.
See #getSchema(Name)  for details.
 public DirContext getSchemaClassDefinition(Name name) throws NamingException
    Retrieves a context containing the schema objects of the
named object's class definitions.

    
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.
 public DirContext getSchemaClassDefinition(String name) throws NamingException
 public  void modifyAttributes(Name name,
    ModificationItem[] mods) throws NamingException
    Modifies the attributes associated with a named object using
an ordered list of modifications.
The modifications are performed
in the order specified.  Each modification specifies a
modification operation code and an attribute on which to
operate.  Where possible, the modifications are
performed atomically.
 public  void modifyAttributes(String name,
    ModificationItem[] mods) throws NamingException
 public  void modifyAttributes(Name name,
    int mod_op,
    Attributes attrs) throws NamingException
    Modifies the attributes associated with a named object.
The order of the modifications is not specified.  Where
possible, the modifications are performed atomically.
 public  void modifyAttributes(String name,
    int mod_op,
    Attributes attrs) throws NamingException
 public  void rebind(Name name,
    Object obj,
    Attributes attrs) throws NamingException
    Binds a name to an object, along with associated attributes,
overwriting any existing binding.
If attrs is null and obj is a DirContext,
the attributes from obj are used.
If attrs is null and obj is not a DirContext,
any existing attributes associated with the object already bound
in the directory remain unchanged.
If attrs is non-null, any existing attributes associated with
the object already bound in the directory are removed and attrs
is associated with the named object.  If obj is a
DirContext and attrs is non-null, the attributes
of obj are ignored.
 public  void rebind(String name,
    Object obj,
    Attributes attrs) throws NamingException
 public NamingEnumeration<SearchResult> search(Name name,
    Attributes matchingAttributes) throws NamingException
    Searches in a single context for objects that contain a
specified set of attributes.
This method returns all the attributes of such objects.
It is equivalent to supplying null as
the atributesToReturn parameter to the method
search(Name, Attributes, String[]).

    
See #search(Name, Attributes, String[])  for a full description.
 public NamingEnumeration<SearchResult> search(String name,
    Attributes matchingAttributes) throws NamingException
    Searches in a single context for objects that contain a
specified set of attributes.
See #search(Name, Attributes)  for details.
 public NamingEnumeration<SearchResult> search(Name name,
    Attributes matchingAttributes,
    String[] attributesToReturn) throws NamingException
    Searches in a single context for objects that contain a
specified set of attributes, and retrieves selected attributes.
The search is performed using the default
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.
 public NamingEnumeration<SearchResult> search(String name,
    Attributes matchingAttributes,
    String[] attributesToReturn) throws NamingException
 public NamingEnumeration<SearchResult> search(Name name,
    String filter,
    SearchControls cons) throws NamingException
    Searches in the named context or object for entries that satisfy the
given search filter.  Performs the search as specified by
the search controls.

    
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.
 public NamingEnumeration<SearchResult> search(String name,
    String filter,
    SearchControls cons) throws NamingException
    Searches in the named context or object for entries that satisfy the
given search filter.  Performs the search as specified by
the search controls.
See #search(Name, String, SearchControls)  for details.
 public NamingEnumeration<SearchResult> search(Name name,
    String filterExpr,
    Object[] filterArgs,
    SearchControls cons) throws NamingException
    Searches in the named context or object for entries that satisfy the
given search filter.  Performs the search as specified by
the search controls.

    
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.
 public NamingEnumeration<SearchResult> search(String name,
    String filterExpr,
    Object[] filterArgs,
    SearchControls cons) throws NamingException