Package org.eclipse.ecf.core.identity

Class Namespace

java.lang.Object
org.eclipse.ecf.core.identity.Namespace
All Implemented Interfaces:
Serializable, org.eclipse.core.runtime.IAdaptable
Direct Known Subclasses:
DnsSdNamespace, FileTransferNamespace, GUID.GUIDNamespace, JSLPNamespace, LongID.LongNamespace, R_OSGiNamespace, R_OSGiRemoteServiceNamespace, RemoteServiceNamespace, RemoteServiceNamespace, RestNamespace, StringID.StringIDNamespace, URIID.URIIDNamespace, UuID.UuIDNamespace
public abstract class Namespace extends Object implements Serializable, org.eclipse.core.runtime.IAdaptable
Namespace base class.

This class and subclasses define a namespace for the creation and management of ID instances. Creation of ID instances is accomplished via the createInstance(Object[]) method, implemented by subclasses of this Namespace superclass.

All Namespace instances must have a unique name passed to the Namespace upon construction.

Typically Namespace instances are created via plugins that define extensions of the org.eclipse.ecf.namespace extension point. For example, to define a new Namespace subclass XMPPNamespace with name "ecf.xmpp" and add it to the ECF extension registry: 

        <extension
             point="org.eclipse.ecf.namespace">
          <namespace
                class="XMPPNamespace"
                name="ecf.xmpp"/>
        </extension>
See Also:

  • Field Details

  • Constructor Details

    • Namespace

      public Namespace()

    • Namespace

      public Namespace(String name, String desc)

  • Method Details

    • initialize

      public final boolean initialize(String n, String desc)

    • equals

      public boolean equals(Object other)
      Override of Object.equals. This equals method returns true if the provided Object is also a Namespace instance, and the names of the two instances match.
      Overrides:
      equals in class Object
      Parameters:
      other - the Object to test for equality

    • hashCode

      public int hashCode()
      Hashcode implementation. Subclasses should not override.
      Overrides:
      hashCode in class Object
      Returns:
      int hashCode for this Namespace. Should be unique.

    • testIDEquals

      protected boolean testIDEquals(BaseID first, BaseID second)
      Test whether two IDs are equal to one another.
      Parameters:
      first - the first ID. Must not be null.
      second - the second ID. Must not be null.
      Returns:
      true if this ID is equal to the given ID. false otherwise.

    • getNameForID

      protected String getNameForID(BaseID id)
      The default implementation of this method is to call id.namespaceGetName(). Subclasses may override.
      Parameters:
      id - the ID to get the name for. Must not be null.
      Returns:
      String that is the unique name for the given id within this Namespace.

    • getCompareToForObject

      protected int getCompareToForObject(BaseID first, BaseID second)
      The default implementation of this method is to call first.namespaceCompareTo(second). Subclasses may override.
      Parameters:
      first - the first id to compare. Must not be null.
      second - the second id to compare. Must not be null.
      Returns:
      int as specified by Comparable.

    • getHashCodeForID

      protected int getHashCodeForID(BaseID id)
      The default implementation of this method is to call id.namespaceHashCode(). Subclasses may override.
      Parameters:
      id - the id in this Namespace to get the hashcode for. Must not be null.
      Returns:
      the hashcode for the given id. Returned value must be unique within this process.

    • toExternalForm

      protected String toExternalForm(BaseID id)
      The default implementation of this method is to call id.namespaceToExternalForm(). Subclasses may override.
      Parameters:
      id - the id in this Namespace to convert to external form.
      Returns:
      String that represents the given id in an external form. Note that this external form may at some later time be passed to createInstance(Object[]) as a single String parameter, and should result in a valid ID instance of the appropriate Namespace.

    • getName

      public String getName()
      Get the name of this namespace. Must not return null.
      Returns:
      String name of Namespace instance. Must not return null, and the returned value should be a globally unique name for this Namespace subclass.

    • getDescription

      public String getDescription()
      Get the description, associated with this Namespace. The returned value may be null.
      Returns:
      the description associated with this Namespace. May be null.

    • createInstance

      public abstract ID createInstance(Object[] parameters) throws IDCreateException
      Make an instance of this namespace. Namespace subclasses, provided by plugins must implement this method to construct ID instances for the given namespace.

      See getSupportedParameterTypes() to get information relevant to deciding what parameter types are expected by this method.

      Parameters:
      parameters - an Object[] of parameters for creating ID instances. May be null.
      Returns:
      a non-null ID instance. The class used may extend BaseID or may implement the ID interface directly
      Throws:
      IDCreateException - if construction fails

    • getScheme

      public abstract String getScheme()
      Get the primary scheme associated with this namespace. Subclasses must provide an implementation that returns a non-null scheme identifier. Note that the returned scheme should not contain the Namespace.SCHEME_SEPARATOR (\":\").
      Returns:
      a String scheme identifier. Must not be null.

    • getSupportedSchemes

      public String[] getSupportedSchemes()
      Get an array of schemes supported by this Namespace instance. Subclasses may override to support multiple schemes.
      Returns:
      String[] of schemes supported by this Namespace. Will not be null, but returned array may be of length 0.

    • getSupportedParameterTypes

      public Class<?>[][] getSupportedParameterTypes()
      Get the supported parameter types for IDs created via subsequent calls to createInstance(Object[]). Callers may use this method to determine the available parameter types, and then create and pass in conforming Object arrays to to createInstance(Object[]).

      An empty two-dimensional array (new Class[0][0]) is the default returned by this abstract superclass. This means that the Object [] passed to createInstance(Object[]) will be ignored.

      Subsclasses should override this method to specify the parameters that they will accept in calls to createInstance(Object[]). The rows of the returned Class array are the acceptable types for a given invocation of createInstance.

      Consider the following example: 

       public Class[][] getSupportedParameterTypes() {
        return new Class[][] { { String.class }, { String.class, String.class } };
 }
      The above means that there are two acceptable values for the Object [] passed into createInstance(Object[]): 1) a single String, and 2) two Strings. These would therefore be acceptable as input to createInstance: 
              ID newID1 = namespace.createInstance(new Object[] { "Hello" });
        ID newID2 = namespace.createInstance(new Object[] { "Hello", "There"}};
      Returns:
      Class [][] an array of class []s. Rows of the returned two-dimensional array define the acceptable parameter types for a single call to createInstance(Object[]). If zero-length Class arrays are returned (i.e. Class[0][0]), then Object [] parameters to createInstance(Object[]) will be ignored.

    • getAdapter

      public Object getAdapter(Class adapter)
      Specified by:
      getAdapter in interface org.eclipse.core.runtime.IAdaptable

    • getInitStringFromExternalForm

      protected String getInitStringFromExternalForm(Object[] args)
      Since:
      3.1

    • toString

      public String toString()
      Overrides:
      toString in class Object