javax.naming
Class InitialContext

java.lang.Object
  |
  +--javax.naming.InitialContext

Direct Known Subclasses:

InitialDirContext

public class InitialContext

extends Object

implements Context

This class is the starting context for performing naming operations.

All naming operations are relative to a context. The initial context implements the Context interface and provides the starting point for resolution of names.

When the initial context is constructed, its environment is initialized with properties defined in the environment parameter passed to the constructor, and in any application resource files. In addition, a small number of standard JNDI properties may be specified as system properties or as applet parameters (through the use of Context.APPLET). These special properties are listed in the field detail sections of the Context and LdapContext interface documentation.

JNDI determines each property's value by merging the values from the following two sources, in order:

1. The first occurrence of the property from the constructor's environment parameter and (for appropriate properties) the applet parameters and system properties.
2. The application resource files (jndi.properties).

For each property found in both of these two sources, or in more than one application resource file, the property's value is determined as follows. If the property is one of the standard JNDI properties that specify a list of JNDI factories (see Context), all of the values are concatenated into a single colon-separated list. For other properties, only the first value found is used.

The initial context implementation is determined at runtime. The default policy uses the environment property "java.naming.factory.initial", which contains the class name of the initial context factory. An exception to this policy is made when resolving URL strings, as described below.

When a URL string (a String of the form scheme_id:rest_of_name) is passed as a name parameter to any method, a URL context factory for handling that scheme is located and used to resolve the URL. If no such factory is found, the initial context specified by "java.naming.factory.initial" is used. Similarly, when a CompositeName object whose first component is a URL string is passed as a name parameter to any method, a URL context factory is located and used to resolve the first name component. See NamingManager.getURLContext() for a description of how URL context factories are located.

This default policy of locating the initial context and URL context factories may be overridden by calling NamingManager.setInitialContextFactoryBuilder().

NoInitialContextException is thrown when an initial context cannot be instantiated. This exception can be thrown during any interaction with the InitialContext, not only when the InitialContext is constructed. For example, the implementation of the initial context might lazily retrieve the context only when actual methods are invoked on it. The application should not have any dependency on when the existence of an initial context is determined.

When the environment property "java.naming.factory.initial" is non-null, the InitialContext constructor will attempt to create the initial context specified therein. At that time, the initial context factory involved might throw an exception if a problem is encountered. However, it is provider implementation-dependent when it verifies and indicates to the users of the initial context any environment property- or connection- related problems. It can do so lazily--delaying until an operation is performed on the context, or eagerly, at the time the context is constructed.

An InitialContext instance is not synchronized against concurrent access by multiple threads. Multiple threads each manipulating a different InitialContext instance need not synchronize. Threads that need to access a single InitialContext instance concurrently should synchronize amongst themselves and provide the necessary locking.

Since:

JNDI 1.1 / Java 2 Platform, Standard Edition, v 1.3

See Also:

Context, NamingManager.setInitialContextFactoryBuilder

Field Summary

protected Context	defaultInitCtx Field holding the result of calling NamingManager.getInitialContext().
protected boolean	gotDefault Field indicating whether the initial context has been obtained by calling NamingManager.getInitialContext().
protected Hashtable	myProps The environment associated with this InitialContext.

Constructor Summary

	InitialContext() Constructs an initial context.
protected	InitialContext(boolean lazy) Constructs an initial context with the option of not initializing it.
	InitialContext(Hashtable environment) Constructs an initial context using the supplied environment.

Method Summary

Object	addToEnvironment(String propName, Object propVal) Adds a new environment property to the environment of this context.
void	bind(Name name, Object obj) Binds a name to an object.
void	bind(String name, Object obj) Binds a name to an object.
void	close() Closes this context.
Name	composeName(Name name, Name prefix) Composes the name of this context with a name relative to this context.
String	composeName(String name, String prefix) Composes the name of this context with a name relative to this context.
Context	createSubcontext(Name name) Creates and binds a new context.
Context	createSubcontext(String name) Creates and binds a new context.
void	destroySubcontext(Name name) Destroys the named context and removes it from the namespace.
void	destroySubcontext(String name) Destroys the named context and removes it from the namespace.
protected Context	getDefaultInitCtx() Retrieves the initial context by calling NamingManager.getInitialContext() and cache it in defaultInitCtx.
Hashtable	getEnvironment() Retrieves the environment in effect for this context.
String	getNameInNamespace() Retrieves the full name of this context within its own namespace.
NameParser	getNameParser(Name name) Retrieves the parser associated with the named context.
NameParser	getNameParser(String name) Retrieves the parser associated with the named context.
protected Context	getURLOrDefaultInitCtx(Name name) Retrieves a context for resolving name.
protected Context	getURLOrDefaultInitCtx(String name) Retrieves a context for resolving the string name name.
protected void	init(Hashtable environment) Initializes the initial context using the supplied environment.
NamingEnumeration	list(Name name) Enumerates the names bound in the named context, along with the class names of objects bound to them.
NamingEnumeration	list(String name) Enumerates the names bound in the named context, along with the class names of objects bound to them.
NamingEnumeration	listBindings(Name name) Enumerates the names bound in the named context, along with the objects bound to them.
NamingEnumeration	listBindings(String name) Enumerates the names bound in the named context, along with the objects bound to them.
Object	lookup(Name name) Retrieves the named object.
Object	lookup(String name) Retrieves the named object.
Object	lookupLink(Name name) Retrieves the named object, following links except for the terminal atomic component of the name.
Object	lookupLink(String name) Retrieves the named object, following links except for the terminal atomic component of the name.
void	rebind(Name name, Object obj) Binds a name to an object, overwriting any existing binding.
void	rebind(String name, Object obj) Binds a name to an object, overwriting any existing binding.
Object	removeFromEnvironment(String propName) Removes an environment property from the environment of this context.
void	rename(Name oldName, Name newName) Binds a new name to the object bound to an old name, and unbinds the old name.
void	rename(String oldName, String newName) Binds a new name to the object bound to an old name, and unbinds the old name.
void	unbind(Name name) Unbinds the named object.
void	unbind(String name) Unbinds the named object.

Methods inherited from class java.lang.Object

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

Field Detail

myProps

protected Hashtable myProps

The environment associated with this InitialContext. It is initialized to null and is updated by the constructor that accepts an environment or by the init() method.

See Also:

addToEnvironment(java.lang.String, java.lang.Object), removeFromEnvironment(java.lang.String), getEnvironment()

defaultInitCtx

protected Context defaultInitCtx

Field holding the result of calling NamingManager.getInitialContext(). It is set by getDefaultInitCtx() the first time getDefaultInitCtx() is called. Subsequent invocations of getDefaultInitCtx() return the value of defaultInitCtx.

See Also:

getDefaultInitCtx()

gotDefault

protected boolean gotDefault

Field indicating whether the initial context has been obtained by calling NamingManager.getInitialContext(). If true, its result is in defaultInitCtx.

Constructor Detail

InitialContext

protected InitialContext(boolean lazy)
                  throws NamingException

Constructs an initial context with the option of not initializing it. This may be used by a constructor in a subclass when the value of the environment parameter is not yet known at the time the InitialContext constructor is called. The subclass's constructor will call this constructor, compute the value of the environment, and then call init() before returning.

Parameters:

lazy - true means do not initialize the initial context; false is equivalent to calling new InitialContext()

Throws:

NamingException - if a naming exception is encountered

Since:

JNDI 1.2 / Java 2 Platform, Standard Edition, v 1.3

See Also:

init(Hashtable)

InitialContext

public InitialContext()
               throws NamingException

Constructs an initial context. No environment properties are supplied. Equivalent to new InitialContext(null).

Throws:

NamingException - if a naming exception is encountered

See Also:

InitialContext(Hashtable)

InitialContext

public InitialContext(Hashtable environment)
               throws NamingException

Constructs an initial context using the supplied environment. Environment properties are discussed in the class description.

This constructor will not modify environment or save a reference to it, but may save a clone.

Parameters:

environment - environment used to create the initial context. Null indicates an empty environment.

Throws:

NamingException - if a naming exception is encountered

Method Detail

init

protected void init(Hashtable environment)
             throws NamingException

Initializes the initial context using the supplied environment. Environment properties are discussed in the class description.

This method will modify environment and save a reference to it. The caller may no longer modify it.

Parameters:

environment - environment used to create the initial context. Null indicates an empty environment.

Throws:

NamingException - if a naming exception is encountered

Since:

JNDI 1.2 / Java 2 Platform, Standard Edition, v 1.3

See Also:

InitialContext(boolean)

getDefaultInitCtx

protected Context getDefaultInitCtx()
                             throws NamingException

Retrieves the initial context by calling NamingManager.getInitialContext() and cache it in defaultInitCtx. Set gotDefault so that we know we've tried this before.

Returns:

The non-null cached initial context.

Throws:

NoInitialContextException - If cannot find an initial context.

NamingException - If a naming exception was encountered.

getURLOrDefaultInitCtx

protected Context getURLOrDefaultInitCtx(String name)
                                  throws NamingException

Retrieves a context for resolving the string name name. If name name is a URL string, then attempt to find a URL context for it. If none is found, or if name is not a URL string, then return getDefaultInitCtx().

See getURLOrDefaultInitCtx(Name) for description of how a subclass should use this method.

Parameters:

name - The non-null name for which to get the context.

Returns:

A URL context for name or the cached initial context. The result cannot be null.

Throws:

NoInitialContextException - If cannot find an initial context.

NamingException - In a naming exception is encountered.

See Also:

NamingManager.getURLContext(java.lang.String, java.util.Hashtable)

getURLOrDefaultInitCtx

protected Context getURLOrDefaultInitCtx(Name name)
                                  throws NamingException

Retrieves a context for resolving name. If the first component of name name is a URL string, then attempt to find a URL context for it. If none is found, or if the first component of name is not a URL string, then return getDefaultInitCtx().

When creating a subclass of InitialContext, use this method as follows. Define a new method that uses this method to get an initial context of the desired subclass.

 protected XXXContext getURLOrDefaultInitXXXCtx(Name name) 
 throws NamingException {
  Context answer = getURLOrDefaultInitCtx(name);
  if (!(answer instanceof XXXContext)) {
    if (answer == null) {
	    throw new NoInitialContextException();
    } else {
	    throw new NotContextException("Not an XXXContext");
    }
 	}
	return (XXXContext)answer;
 }
 

When providing implementations for the new methods in the subclass, use this newly defined method to get the initial context.

 public Object XXXMethod1(Name name, ...) {
	throws NamingException {
    return getURLOrDefaultInitXXXCtx(name).XXXMethod1(name, ...);
 }
 

Parameters:

name - The non-null name for which to get the context.

Returns:

A URL context for name or the cached initial context. The result cannot be null.

Throws:

NoInitialContextException - If cannot find an initial context.

NamingException - In a naming exception is encountered.

See Also:

NamingManager.getURLContext(java.lang.String, java.util.Hashtable)

lookup

public Object lookup(String name)
              throws NamingException

Retrieves the named object.

Specified by:

lookup in interface Context

lookup

public Object lookup(Name name)
              throws NamingException

Retrieves the named object.

Specified by:

lookup in interface Context

bind

public void bind(String name,
                 Object obj)
          throws NamingException

Binds a name to an object.

Specified by:

bind in interface Context

bind

public void bind(Name name,
                 Object obj)
          throws NamingException

Binds a name to an object.

Specified by:

bind in interface Context

rebind

public void rebind(String name,
                   Object obj)
            throws NamingException

Binds a name to an object, overwriting any existing binding.

Specified by:

rebind in interface Context

rebind

public void rebind(Name name,
                   Object obj)
            throws NamingException

Binds a name to an object, overwriting any existing binding.

Specified by:

rebind in interface Context

unbind

public void unbind(String name)
            throws NamingException

Unbinds the named object.

Specified by:

unbind in interface Context

unbind

public void unbind(Name name)
            throws NamingException

Unbinds the named object.

Specified by:

unbind in interface Context

rename

public void rename(String oldName,
                   String newName)
            throws NamingException

Binds a new name to the object bound to an old name, and unbinds the old name.

Specified by:

rename in interface Context

rename

public void rename(Name oldName,
                   Name newName)
            throws NamingException

Binds a new name to the object bound to an old name, and unbinds the old name.

Specified by:

rename in interface Context

list

public NamingEnumeration list(String name)
                       throws NamingException

Enumerates the names bound in the named context, along with the class names of objects bound to them.

Specified by:

list in interface Context

list

public NamingEnumeration list(Name name)
                       throws NamingException

Enumerates the names bound in the named context, along with the class names of objects bound to them.

Specified by:

list in interface Context

listBindings

public NamingEnumeration listBindings(String name)
                               throws NamingException

Enumerates the names bound in the named context, along with the objects bound to them.

Specified by:

listBindings in interface Context

listBindings

public NamingEnumeration listBindings(Name name)
                               throws NamingException

Enumerates the names bound in the named context, along with the objects bound to them.

Specified by:

listBindings in interface Context

destroySubcontext

public void destroySubcontext(String name)
                       throws NamingException

Destroys the named context and removes it from the namespace.

Specified by:

destroySubcontext in interface Context

destroySubcontext

public void destroySubcontext(Name name)
                       throws NamingException

Destroys the named context and removes it from the namespace.

Specified by:

destroySubcontext in interface Context

createSubcontext

public Context createSubcontext(String name)
                         throws NamingException

Creates and binds a new context.

Specified by:

createSubcontext in interface Context

createSubcontext

public Context createSubcontext(Name name)
                         throws NamingException

Creates and binds a new context.

Specified by:

createSubcontext in interface Context

lookupLink

public Object lookupLink(String name)
                  throws NamingException

Retrieves the named object, following links except for the terminal atomic component of the name.

Specified by:

lookupLink in interface Context

lookupLink

public Object lookupLink(Name name)
                  throws NamingException

Retrieves the named object, following links except for the terminal atomic component of the name.

Specified by:

lookupLink in interface Context

getNameParser

public NameParser getNameParser(String name)
                         throws NamingException

Retrieves the parser associated with the named context.

Specified by:

getNameParser in interface Context

getNameParser

public NameParser getNameParser(Name name)
                         throws NamingException

Retrieves the parser associated with the named context.

Specified by:

getNameParser in interface Context

composeName

public String composeName(String name,
                          String prefix)
                   throws NamingException

Composes the name of this context with a name relative to this context. Since an initial context may never be named relative to any context other than itself, the value of the prefix parameter must be an empty name ("").

Specified by:

composeName in interface Context

composeName

public Name composeName(Name name,
                        Name prefix)
                 throws NamingException

Composes the name of this context with a name relative to this context. Since an initial context may never be named relative to any context other than itself, the value of the prefix parameter must be an empty name.

Specified by:

composeName in interface Context

addToEnvironment

public Object addToEnvironment(String propName,
                               Object propVal)
                        throws NamingException

Adds a new environment property to the environment of this context.

Specified by:

addToEnvironment in interface Context

removeFromEnvironment

public Object removeFromEnvironment(String propName)
                             throws NamingException

Removes an environment property from the environment of this context.

Specified by:

removeFromEnvironment in interface Context

getEnvironment

public Hashtable getEnvironment()
                         throws NamingException

Retrieves the environment in effect for this context.

Specified by:

getEnvironment in interface Context

close

public void close()
           throws NamingException

Closes this context.

Specified by:

close in interface Context

getNameInNamespace

public String getNameInNamespace()
                          throws NamingException

Retrieves the full name of this context within its own namespace.

Specified by:

getNameInNamespace in interface Context