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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

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package com.sun.jndi.toolkit.ctx;

import javax.naming.*;

import javax.naming.spi.ResolveResult;

import java.util.Hashtable;

/**

  * This class contains information required to continue

  * the method (place where it left off, and remaining name to

  * continue).

  *

  * @author Rosanna Lee

  */

public class Continuation extends ResolveResult {

    /**

     * The name that we started out with. It is initialized by the constructor

     * and used to calculate to "resolved name" in NamingException in

     * fillInException().

     * %%% Note that this approach does not always do the calculation

     * correctly with respect to absence or presence of the trailing slash

     * for resolved name.

     */

    protected Name starter;

    /**

     * Whether links were encountered.

     */

    protected Object followingLink = null;

    /**

     * The environment used by the caller. Initialized by constructor and

     * used when filling out a CannotProceedException.

     */

    protected Hashtable<?,?> environment = null;

    /**

     * Indicates whether the Continuation instance indicates that the operation

     * should be continued using the data in the Continuation.

     * Typically, this is only false if an error has been encountered or if

     * the operation has succeeded.

     */

    protected boolean continuing = false;

    /**

     * The last resolved context. Used to set the "AltNameCtx" in a

     * CannotProceedException.

     */

    protected Context resolvedContext = null;

    /**

     * The resolved name relative to resolvedContext. Used to set the

     * "AltName" in a CannotProceedException.

     */

    protected Name relativeResolvedName = null;

    /**

     * Constructs a new instance of Continuation.

     * Used as dummy for contexts that do not do federation (e.g. for schema ops)

     */

    public Continuation() {

    }

    /**

     * Constructs a new instance of Continuation.

     * @param top The name of the object that is to be resolved/operated upon.

     *          This becomes the Continuation's 'starter' and is used to

     *          calculate the "resolved name" when filling in a NamingException.

     * @param environment The environment used by the caller. It is used

     *          when setting the "environment" of a CannotProceedException.

     */

    @SuppressWarnings("unchecked")  // For Hashtable clone: environment.clone()

    public Continuation(Name top, Hashtable<?,?> environment) {

        super();

        starter = top;

        this.environment = (Hashtable<?,?>)

                ((environment == null) ? null : environment.clone());

    }

    /**

     * Determines whether this Continuation contains data that should be

     * used to continue the operation.

     *

     * @return true if operation should continue; false if operation has

     * completed (successfully or unsuccessfully).

     */

    public boolean isContinue() {

        return continuing;

    }

    /**

     * Sets this Continuation to indicate successful completion.

     * Subsequent calls to isContinue() will return false.

     * This method is different from the setError() methods only from

     * the standpoint that this method does not set any of the other

     * fields such as resolved object or resolved context. This is because

     * this method is typically called when the context recognizes that

     * the operation has successfully completed and that the continuation

     * already contains the appropriately set fields.

     * @see setError

     * @see setErrorNNS

     */

    public void setSuccess() {

        continuing = false;

    }

    /**

     * Fills in an exception's fields using data from this Continuation.

     * The resolved name is set by subtracting remainingName from starter.

     * %%% This might not not always produce the correct answer wrt trailing "/".

     * If the exception is a CannotProceedException, its environment,

     * altName, and altNameCtx fields are set using this continuation's

     * environment, relativeResolvedName, and resolvedContext.

     *

     * @param e The non-null naming exception to fill.

     * @return The non-null naming exception with its fields set using

     * data from this Continuation.

     */

    public NamingException fillInException(NamingException e) {

        e.setRemainingName(remainingName);

        e.setResolvedObj(resolvedObj);

        if (starter == null || starter.isEmpty())

            e.setResolvedName(null);

        else if (remainingName == null)

            e.setResolvedName(starter);

        else

            e.setResolvedName(

                starter.getPrefix(starter.size() -

                                  remainingName.size()));

        if ((e instanceof CannotProceedException)) {

            CannotProceedException cpe = (CannotProceedException)e;

            Hashtable<?,?> env = (environment == null ?

                new Hashtable<>(11) : (Hashtable<?,?>)environment.clone());

            cpe.setEnvironment(env);

            cpe.setAltNameCtx(resolvedContext);

            cpe.setAltName(relativeResolvedName);

        }

        return e;

    }

    /**

     * Sets this Continuation to indicated that an error has occurred,

     * and that the remaining name is rename + "/".

     *

     * This method is typically called by _nns methods that have been

     * given a name to process. It might process part of that name but

     * encountered some error. Consequently, it would call setErrorNNS()

     * with the remaining name. Since the _nns method was expected to

     * operate upon the "nns" of the original name, the remaining name

     * must include the "nns". That's why this method adds a trailing "/".

     *<p>

     * After this method is called, isContinuing() returns false.

     *

     * @param resObj The possibly null object that was resolved to.

     * @param remain The non-null remaining name.

     */

    public void setErrorNNS(Object resObj, Name remain) {

        Name nm = (Name)(remain.clone());

        try {

            nm.add("");

        } catch (InvalidNameException e) {

            // ignore; can't happen for composite name

        }

        setErrorAux(resObj, nm);

    }

    /**

     * Form that accepts a String name instead of a Name name.

     * @param resObj The possibly null object that was resolved to.

     * @param remain The possibly String remaining name.

     *

     * @see #setErrorNNS(java.lang.Object, javax.naming.Name)

     */

    public void setErrorNNS(Object resObj, String remain) {

        CompositeName rname = new CompositeName();

        try {

                rname.add(remain);

            rname.add("");

        } catch (InvalidNameException e) {

            // ignore, can't happen for composite name

        }

        setErrorAux(resObj, rname);

    }

    /**

     * Sets this Continuation to indicated that an error has occurred

     * and supply resolved information.

     *

     * This method is typically called by methods that have been

     * given a name to process. It might process part of that name but

     * encountered some error. Consequently, it would call setError()

     * with the resolved object and the remaining name.

     *<p>

     * After this method is called, isContinuing() returns false.

     *

     * @param resObj The possibly null object that was resolved to.

     * @param remain The possibly null remaining name.

     */

    public void setError(Object resObj, Name remain) {

        if (remain != null)

            remainingName = (Name)(remain.clone());

        else

            remainingName = null;

        setErrorAux(resObj, remainingName);

    }

    /**

     * Form that accepts a String name instead of a Name name.

     * @param resObj The possibly null object that was resolved to.

     * @param remain The possibly String remaining name.

     *

     * @see #setError(java.lang.Object, javax.naming.Name)

     */

    public void setError(Object resObj, String remain) {

        CompositeName rname = new CompositeName();

            try {

                rname.add(remain);

            } catch (InvalidNameException e) {

                // ignore; can't happen for composite name

            }

        }

        setErrorAux(resObj, rname);

    }

    private void setErrorAux(Object resObj, Name rname) {

        remainingName = rname;

        resolvedObj = resObj;

        continuing = false;

    }

    private void setContinueAux(Object resObj,

        Name relResName, Context currCtx,  Name remain) {

        if (resObj instanceof LinkRef) {

            setContinueLink(resObj, relResName, currCtx, remain);

        } else {

            remainingName = remain;

            resolvedObj = resObj;

            relativeResolvedName = relResName;

            resolvedContext = currCtx;

            continuing = true;

        }

    }

    /**

     * Sets this Continuation with the supplied data, and set remaining name

     * to be "/".

     * This method is typically called by _nns methods that have been

     * given a name to process. It might the name (without the nns) and

     * continue process of the nns elsewhere.

     * Consequently, it would call this form of the setContinueNNS().

     * This method supplies "/" as the remaining name.

     *<p>

     * After this method is called, isContinuing() returns true.

     *

     * @param resObj The possibly null resolved object.

     * @param relResName The non-null resolved name relative to currCtx.

     * @param currCtx The non-null context from which relResName is to be resolved.

     */

    public void setContinueNNS(Object resObj, Name relResName, Context currCtx) {

        CompositeName rname = new CompositeName();

        setContinue(resObj, relResName, currCtx, PartialCompositeContext._NNS_NAME);

    }

    /**

     * Overloaded form that accesses String names.

     *

     * @param resObj The possibly null resolved object.

     * @param relResName The non-null resolved name relative to currCtx.

     * @param currCtx The non-null context from which relResName is to be resolved.

     * @see #setContinueNNS(java.lang.Object, javax.naming.Name, javax.naming.Context)

     */

    public void setContinueNNS(Object resObj, String relResName, Context currCtx) {

        CompositeName relname = new CompositeName();

        try {

            relname.add(relResName);

        } catch (NamingException e) {}

        setContinue(resObj, relname, currCtx, PartialCompositeContext._NNS_NAME);

    }

    /**

     * Sets this Continuation with the supplied data, and set remaining name

     * to be the empty name.

     * This method is typically called by list-style methods

     * in which the target context implementing list() expects an

     * empty name. For example when c_list() is given a non-empty name to

     * process, it would resolve that name, and then call setContinue()

     * with the resolved object so that the target context to be listed

     * would be called with the empty name (i.e. list the target context itself).

     *<p>

     * After this method is called, isContinuing() returns true.

     *

     * @param obj The possibly null resolved object.

     * @param relResName The non-null resolved name relative to currCtx.

     * @param currCtx The non-null context from which relResName is to be resolved.

     */

    public void setContinue(Object obj, Name relResName, Context currCtx) {

        setContinueAux(obj, relResName, currCtx,

            (Name)PartialCompositeContext._EMPTY_NAME.clone());

    }

    /**

     * Sets this Continuation with the supplied data.

     * This method is typically called by a method that has been asked

     * to operate on a name. The method resolves part of the name

     * (relResName) to obj and sets the unprocessed part to rename.

     * It calls setContinue() so that the operation can be continued

     * using this data.

     *<p>

     * After this method is called, isContinuing() returns true.

     *

     * @param obj The possibly null resolved object.

     * @param relResName The non-null resolved name relative to currCtx.

     * @param currCtx The non-null context from which relResName is to be resolved.

     * @param remain The non-null remaining name.

     */

    public void setContinue(Object obj, Name relResName, Context currCtx, Name remain) {

        if (remain != null)

            this.remainingName = (Name)(remain.clone());

        else

            this.remainingName = new CompositeName();

        setContinueAux(obj, relResName, currCtx, remainingName);

    }

    /**

     * String overload.

     *

     * @param obj The possibly null resolved object.

     * @param relResName The non-null resolved name relative to currCtx.

     * @param currCtx The non-null context from which relResName is to be resolved.

     * @param remain The non-null remaining name.

     * @see #setContinue(java.lang.Object, java.lang.String, javax.naming.Context, java.lang.String)

     */

    public void setContinue(Object obj, String relResName,

        Context currCtx, String remain) {

        CompositeName relname = new CompositeName();

            try {

                relname.add(relResName);

            } catch (NamingException e){}

        }

        CompositeName rname = new CompositeName();

            try {

                rname.add(remain);

            } catch (NamingException e) {

            }

        }

        setContinueAux(obj, relname, currCtx, rname);

    }

    /**

     * %%% This method is kept only for backward compatibility. Delete when

     * old implementations updated.

     *

     * Replaced by setContinue(obj, relResName, (Context)currCtx);

     *

     * @deprecated

     */

    @Deprecated

    public void setContinue(Object obj, Object currCtx) {

        setContinue(obj, null, (Context)currCtx);

    }

    /**

     * Sets this Continuation to process a linkRef.

     * %%% Not working yet.

     */

    private void setContinueLink(Object linkRef, Name relResName,

        Context resolvedCtx, Name rname) {

        this.followingLink = linkRef;

        this.remainingName = rname;

        this.resolvedObj = resolvedCtx;

        this.relativeResolvedName = PartialCompositeContext._EMPTY_NAME;

        this.resolvedContext = resolvedCtx;

        this.continuing = true;

    }

    public String toString() {

        if (remainingName != null)

            return starter.toString() + "; remainingName: '" + remainingName + "'";

        else

            return starter.toString();

    }

    public String toString(boolean detail) {

        if (!detail || this.resolvedObj == null)

                return this.toString();

        return this.toString() + "; resolvedObj: " + this.resolvedObj +

            "; relativeResolvedName: " + relativeResolvedName +

            "; resolvedContext: " + resolvedContext;

    }

    private static final long serialVersionUID = 8162530656132624308L;

}