AbstractAdHocCommand.java
/**
*
* Copyright 2005-2007 Jive Software.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.jivesoftware.smackx.commands;
import java.util.ArrayList;
import java.util.List;
import java.util.Set;
import org.jivesoftware.smack.SmackException.NoResponseException;
import org.jivesoftware.smack.SmackException.NotConnectedException;
import org.jivesoftware.smack.XMPPException.XMPPErrorException;
import org.jivesoftware.smack.packet.StanzaError;
import org.jivesoftware.smack.util.StringUtils;
import org.jivesoftware.smackx.commands.packet.AdHocCommandData;
import org.jivesoftware.smackx.commands.packet.AdHocCommandData.Action;
import org.jivesoftware.smackx.commands.packet.AdHocCommandData.AllowedAction;
import org.jivesoftware.smackx.commands.packet.AdHocCommandData.Status;
/**
* An ad-hoc command is responsible for executing the provided service and
* storing the result of the execution. Each new request will create a new
* instance of the command, allowing information related to executions to be
* stored in it. For example suppose that a command that retrieves the list of
* users on a server is implemented. When the command is executed it gets that
* list and the result is stored as a form in the command instance, i.e. the
* <code>getForm</code> method retrieves a form with all the users.
* <p>
* Each command has a <code>node</code> that should be unique within a given JID.
* </p>
* <p>
* Commands may have zero or more stages. Each stage is usually used for
* gathering information required for the command execution. Users are able to
* move forward or backward across the different stages. Commands may not be
* cancelled while they are being executed. However, users may request the
* "cancel" action when submitting a stage response indicating that the command
* execution should be aborted. Thus, releasing any collected information.
* Commands that require user interaction (i.e. have more than one stage) will
* have to provide the data forms the user must complete in each stage and the
* allowed actions the user might perform during each stage (e.g. go to the
* previous stage or go to the next stage).
* </p>
* All the actions may throw an XMPPException if there is a problem executing
* them. The <code>XMPPError</code> of that exception may have some specific
* information about the problem. The possible extensions are:
* <ul>
* <li><i>malformed-action</i>. Extension of a <i>bad-request</i> error.</li>
* <li><i>bad-action</i>. Extension of a <i>bad-request</i> error.</li>
* <li><i>bad-locale</i>. Extension of a <i>bad-request</i> error.</li>
* <li><i>bad-payload</i>. Extension of a <i>bad-request</i> error.</li>
* <li><i>bad-sessionid</i>. Extension of a <i>bad-request</i> error.</li>
* <li><i>session-expired</i>. Extension of a <i>not-allowed</i> error.</li>
* </ul>
* <p>
* See the <code>SpecificErrorCondition</code> class for detailed description
* of each one.
* </p>
* Use the <code>getSpecificErrorConditionFrom</code> to obtain the specific
* information from an <code>XMPPError</code>.
*
* @author Gabriel Guardincerri
* @author Florian Schmaus
*
*/
public abstract class AbstractAdHocCommand {
private final List<AdHocCommandData> requests = new ArrayList<>();
private final List<AdHocCommandResult> results = new ArrayList<>();
private final String node;
private final String name;
/**
* The session ID of this execution.
*/
private String sessionId;
protected AbstractAdHocCommand(String node, String name) {
this.node = StringUtils.requireNotNullNorEmpty(node, "Ad-Hoc command node must be given");
this.name = name;
}
protected AbstractAdHocCommand(String node) {
this(node, null);
}
void addRequest(AdHocCommandData request) {
requests.add(request);
}
void addResult(AdHocCommandResult result) {
results.add(result);
}
/**
* Returns the specific condition of the <code>error</code> or <code>null</code> if the
* error doesn't have any.
*
* @param error the error the get the specific condition from.
* @return the specific condition of this error, or null if it doesn't have
* any.
*/
public static SpecificErrorCondition getSpecificErrorCondition(StanzaError error) {
// This method is implemented to provide an easy way of getting a packet
// extension of the XMPPError.
for (SpecificErrorCondition condition : SpecificErrorCondition.values()) {
if (error.getExtension(condition.toString(),
AdHocCommandData.SpecificError.namespace) != null) {
return condition;
}
}
return null;
}
/**
* Returns the human readable name of the command.
*
* @return the human readable name of the command
*/
public String getName() {
return name;
}
/**
* Returns the unique identifier of the command. It is unique for the
* <code>OwnerJID</code>.
*
* @return the unique identifier of the command.
*/
public String getNode() {
return node;
}
public String getSessionId() {
return sessionId;
}
protected void setSessionId(String sessionId) {
assert this.sessionId == null || this.sessionId.equals(sessionId);
this.sessionId = StringUtils.requireNotNullNorEmpty(sessionId, "Must provide a session ID");
}
public AdHocCommandData getLastRequest() {
if (requests.isEmpty()) return null;
return requests.get(requests.size() - 1);
}
public AdHocCommandResult getLastResult() {
if (results.isEmpty()) return null;
return results.get(results.size() - 1);
}
/**
* Returns the notes that the command has at the current stage.
*
* @return a list of notes.
*/
public List<AdHocCommandNote> getNotes() {
AdHocCommandResult result = getLastResult();
if (result == null) return null;
return result.getResponse().getNotes();
}
/**
* Cancels the execution of the command. This can be invoked on any stage of
* the execution. If there is a problem executing the command it throws an
* XMPPException.
*
* @throws NoResponseException if there was no response from the remote entity.
* @throws XMPPErrorException if there is a problem executing the command.
* @throws NotConnectedException if the XMPP connection is not connected.
* @throws InterruptedException if the calling thread was interrupted.
*/
public abstract void cancel() throws NoResponseException, XMPPErrorException, NotConnectedException, InterruptedException;
/**
* Returns a collection with the allowed actions based on the current stage.
* Possible actions are: {@link AllowedAction#prev prev}, {@link AllowedAction#next next} and
* {@link AllowedAction#complete complete}. This method will be only invoked for commands that
* have one or more stages.
*
* @return a collection with the allowed actions based on the current stage
* as defined in the SessionData.
*/
public final Set<AllowedAction> getActions() {
AdHocCommandResult result = getLastResult();
if (result == null) return null;
return result.getResponse().getActions();
}
/**
* Returns the action available for the current stage which is
* considered the equivalent to "execute". When the requester sends his
* reply, if no action was defined in the command then the action will be
* assumed "execute" thus assuming the action returned by this method. This
* method will never be invoked for commands that have no stages.
*
* @return the action available for the current stage which is considered
* the equivalent to "execute".
*/
protected AllowedAction getExecuteAction() {
AdHocCommandResult result = getLastResult();
if (result == null) return null;
return result.getResponse().getExecuteAction();
}
/**
* Returns the status of the current stage.
*
* @return the current status.
*/
public Status getStatus() {
AdHocCommandResult result = getLastResult();
if (result == null) return null;
return result.getResponse().getStatus();
}
/**
* Check if this command has been completed successfully.
*
* @return <code>true</code> if this command is completed.
* @since 4.2
*/
public boolean isCompleted() {
return getStatus() == AdHocCommandData.Status.completed;
}
/**
* Returns true if the <code>action</code> is available in the current stage.
* The {@link Action#cancel cancel} action is always allowed. To define the
* available actions use the <code>addActionAvailable</code> method.
*
* @param action The action to check if it is available.
* @return True if the action is available for the current stage.
*/
public final boolean isValidAction(Action action) {
if (action == Action.cancel) {
return true;
}
final AllowedAction executeAction;
if (action == Action.execute) {
AdHocCommandResult result = getLastResult();
executeAction = result.getResponse().getExecuteAction();
// This is basically the case that was clarified with
// https://github.com/xsf/xeps/commit/fdaee2da8ffd34b5b5151e90ef1df8b396a06531 and
// https://github.com/xsf/xeps/pull/591.
if (executeAction == null) {
return false;
}
} else {
executeAction = action.allowedAction;
assert executeAction != null;
}
Set<AllowedAction> actions = getActions();
return actions != null && actions.contains(executeAction);
}
}