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package sun.security.jgss;

import org.ietf.jgss.GSSContext;
import org.ietf.jgss.GSSCredential;

The extending point of basic JGSS-API.

If a module wants to extend basic JGSS-API classes, it should extends this
class and register itself as "the extender" using the setExtender method.
When various GSSManager.createXXX methods are called, they will call
"the extender"'s wrap methods to create objects of extended types
instead of basic types.
 We have only one extension now defined in com.sun.security.jgss, and the registering process is triggered in GSSManagerImpl by calling Class.forName("com.sun.security.jgss.Extender"). Only GSSContext and GSSCredential are extended now. 

The setExtender method should be called before any JGSS call.
/**
 * The extending point of basic JGSS-API.
 * <p>
 * If a module wants to extend basic JGSS-API classes, it should extends this
 * class and register itself as "the extender" using the setExtender method.
 * When various GSSManager.createXXX methods are called, they will call
 * "the extender"'s wrap methods to create objects of extended types
 * instead of basic types.
 * <p>
 * We have only one extension now defined in com.sun.security.jgss, and the
 * registering process is triggered in {@link GSSManagerImpl} by calling
 * Class.forName("com.sun.security.jgss.Extender"). Only GSSContext
 * and GSSCredential are extended now.
 * <p>
 * The setExtender method should be called before any JGSS call.
 */
public class JgssExtender {

    // "The extender"
    private static volatile JgssExtender theOne = new JgssExtender();

    
Gets "the extender". GSSManager calls this method so that it can
wrap basic objects into extended objects.
Returns:
the extender/**
     * Gets "the extender". GSSManager calls this method so that it can
     * wrap basic objects into extended objects.
     * @return the extender
     */
    public static JgssExtender getExtender() {
        return theOne;
    }

    
Set "the extender" so that GSSManager can create extended objects.
/**
     * Set "the extender" so that GSSManager can create extended objects.
     */
    protected static void setExtender(JgssExtender theOne) {
        JgssExtender.theOne = theOne;
    }

    
Wraps a plain GSSCredential object into an extended type.
/**
     * Wraps a plain GSSCredential object into an extended type.
     */
    public GSSCredential wrap(GSSCredential cred) {
        return cred;
    }

    
Wraps a plain GSSContext object into an extended type.
/**
     * Wraps a plain GSSContext object into an extended type.
     */
    public GSSContext wrap(GSSContext ctxt) {
        return ctxt;
    }
}