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javax.naming
public class: InitialContext [javadoc | source]
java.lang.Object
   javax.naming.InitialContext

All Implemented Interfaces:
    Context

Direct Known Subclasses:
    InitialLdapContext, InitialDirContext

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.

Field Summary
protected  Hashtable<Object, Object> 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. 
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. 
protected  boolean gotDefault    Field indicating whether the initial context has been obtained by calling NamingManager.getInitialContext(). If true, its result is in defaultInitCtx
Constructor:
 public InitialContext() throws NamingException 
    Constructs an initial context. No environment properties are supplied. Equivalent to new InitialContext(null).
 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
    Also see:
    init(Hashtable)
    since: 1.3 -
 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. Caller should not modify mutable keys and values in environment after it has been passed to the constructor.

    Parameters:
    environment - environment used to create the initial context. Null indicates an empty environment.
    Throws:
    NamingException - if a naming exception is encountered
Method from javax.naming.InitialContext Summary:
addToEnvironment,   bind,   bind,   close,   composeName,   composeName,   createSubcontext,   createSubcontext,   destroySubcontext,   destroySubcontext,   doLookup,   doLookup,   getDefaultInitCtx,   getEnvironment,   getNameInNamespace,   getNameParser,   getNameParser,   getURLOrDefaultInitCtx,   getURLOrDefaultInitCtx,   init,   list,   list,   listBindings,   listBindings,   lookup,   lookup,   lookupLink,   lookupLink,   rebind,   rebind,   removeFromEnvironment,   rename,   rename,   unbind,   unbind
Methods from java.lang.Object:
clone,   equals,   finalize,   getClass,   hashCode,   notify,   notifyAll,   toString,   wait,   wait,   wait
Method from javax.naming.InitialContext Detail:
 public Object addToEnvironment(String propName,
    Object propVal) throws NamingException 
 public  void bind(String name,
    Object obj) throws NamingException 
 public  void bind(Name name,
    Object obj) throws NamingException 
 public  void close() throws NamingException 
 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 ("").
 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.
 public Context createSubcontext(String name) throws NamingException 
 public Context createSubcontext(Name name) throws NamingException 
 public  void destroySubcontext(String name) throws NamingException 
 public  void destroySubcontext(Name name) throws NamingException 
 public static T doLookup(Name name) throws NamingException 
    A static method to retrieve the named object. This is a shortcut method equivalent to invoking:

    InitialContext ic = new InitialContext(); Object obj = ic.lookup();

    If name is empty, returns a new instance of this context (which represents the same naming context as this context, but its environment may be modified independently and it may be accessed concurrently).

 public static T doLookup(String name) throws NamingException 
    A static method to retrieve the named object. See #doLookup(Name) for details.
 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.
 public Hashtable<?, ?> getEnvironment() throws NamingException 
 public String getNameInNamespace() throws NamingException 
 public NameParser getNameParser(String name) throws NamingException 
 public NameParser getNameParser(Name name) throws NamingException 
 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.

 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, ...);
    }
    
 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.

 public NamingEnumeration<NameClassPair> list(String name) throws NamingException 
 public NamingEnumeration<NameClassPair> list(Name name) throws NamingException 
 public NamingEnumeration<Binding> listBindings(String name) throws NamingException 
 public NamingEnumeration<Binding> listBindings(Name name) throws NamingException 
 public Object lookup(String name) throws NamingException 
 public Object lookup(Name name) throws NamingException 
 public Object lookupLink(String name) throws NamingException 
 public Object lookupLink(Name name) throws NamingException 
 public  void rebind(String name,
    Object obj) throws NamingException 
 public  void rebind(Name name,
    Object obj) throws NamingException 
 public Object removeFromEnvironment(String propName) throws NamingException 
 public  void rename(String oldName,
    String newName) throws NamingException 
 public  void rename(Name oldName,
    Name newName) throws NamingException 
 public  void unbind(String name) throws NamingException 
 public  void unbind(Name name) throws NamingException