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      1 /*
      2  * Copyright (C) 2013 The Android Open Source Project
      3  *
      4  * Licensed under the Apache License, Version 2.0 (the "License");
      5  * you may not use this file except in compliance with the License.
      6  * You may obtain a copy of the License at
      7  *
      8  *      http://www.apache.org/licenses/LICENSE-2.0
      9  *
     10  * Unless required by applicable law or agreed to in writing, software
     11  * distributed under the License is distributed on an "AS IS" BASIS,
     12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
     13  * See the License for the specific language governing permissions and
     14  * limitations under the License.
     15  */
     16 
     17 package android.print;
     18 
     19 import android.annotation.NonNull;
     20 import android.annotation.Nullable;
     21 import android.app.Activity;
     22 import android.app.Application.ActivityLifecycleCallbacks;
     23 import android.content.ComponentName;
     24 import android.content.Context;
     25 import android.content.IntentSender;
     26 import android.content.IntentSender.SendIntentException;
     27 import android.graphics.drawable.Icon;
     28 import android.os.Bundle;
     29 import android.os.CancellationSignal;
     30 import android.os.Handler;
     31 import android.os.ICancellationSignal;
     32 import android.os.Looper;
     33 import android.os.Message;
     34 import android.os.ParcelFileDescriptor;
     35 import android.os.RemoteException;
     36 import android.print.PrintDocumentAdapter.LayoutResultCallback;
     37 import android.print.PrintDocumentAdapter.WriteResultCallback;
     38 import android.printservice.PrintServiceInfo;
     39 import android.printservice.recommendation.IRecommendationsChangeListener;
     40 import android.printservice.recommendation.RecommendationInfo;
     41 import android.text.TextUtils;
     42 import android.util.ArrayMap;
     43 import android.util.Log;
     44 
     45 import com.android.internal.os.SomeArgs;
     46 
     47 import com.android.internal.util.Preconditions;
     48 import libcore.io.IoUtils;
     49 
     50 import java.lang.ref.WeakReference;
     51 import java.util.ArrayList;
     52 import java.util.Arrays;
     53 import java.util.Collections;
     54 import java.util.List;
     55 import java.util.Map;
     56 
     57 /**
     58  * System level service for accessing the printing capabilities of the platform.
     59  * <p>
     60  * To obtain a handle to the print manager do the following:
     61  * </p>
     62  *
     63  * <pre>
     64  * PrintManager printManager =
     65  *         (PrintManager) context.getSystemService(Context.PRINT_SERVICE);
     66  * </pre>
     67  *
     68  * <h3>Print mechanics</h3>
     69  * <p>
     70  * The key idea behind printing on the platform is that the content to be printed
     71  * should be laid out for the currently selected print options resulting in an
     72  * optimized output and higher user satisfaction. To achieve this goal the platform
     73  * declares a contract that the printing application has to follow which is defined
     74  * by the {@link PrintDocumentAdapter} class. At a higher level the contract is that
     75  * when the user selects some options from the print UI that may affect the way
     76  * content is laid out, for example page size, the application receives a callback
     77  * allowing it to layout the content to better fit these new constraints. After a
     78  * layout pass the system may ask the application to render one or more pages one
     79  * or more times. For example, an application may produce a single column list for
     80  * smaller page sizes and a multi-column table for larger page sizes.
     81  * </p>
     82  * <h3>Print jobs</h3>
     83  * <p>
     84  * Print jobs are started by calling the {@link #print(String, PrintDocumentAdapter,
     85  * PrintAttributes)} from an activity which results in bringing up the system print
     86  * UI. Once the print UI is up, when the user changes a selected print option that
     87  * affects the way content is laid out the system starts to interact with the
     88  * application following the mechanics described the section above.
     89  * </p>
     90  * <p>
     91  * Print jobs can be in {@link PrintJobInfo#STATE_CREATED created}, {@link
     92  * PrintJobInfo#STATE_QUEUED queued}, {@link PrintJobInfo#STATE_STARTED started},
     93  * {@link PrintJobInfo#STATE_BLOCKED blocked}, {@link PrintJobInfo#STATE_COMPLETED
     94  * completed}, {@link PrintJobInfo#STATE_FAILED failed}, and {@link
     95  * PrintJobInfo#STATE_CANCELED canceled} state. Print jobs are stored in dedicated
     96  * system spooler until they are handled which is they are cancelled or completed.
     97  * Active print jobs, ones that are not cancelled or completed, are considered failed
     98  * if the device reboots as the new boot may be after a very long time. The user may
     99  * choose to restart such print jobs. Once a print job is queued all relevant content
    100  * is stored in the system spooler and its lifecycle becomes detached from this of
    101  * the application that created it.
    102  * </p>
    103  * <p>
    104  * An applications can query the print spooler for current print jobs it created
    105  * but not print jobs created by other applications.
    106  * </p>
    107  *
    108  * @see PrintJob
    109  * @see PrintJobInfo
    110  */
    111 public final class PrintManager {
    112 
    113     private static final String LOG_TAG = "PrintManager";
    114 
    115     private static final boolean DEBUG = false;
    116 
    117     private static final int MSG_NOTIFY_PRINT_JOB_STATE_CHANGED = 1;
    118     private static final int MSG_NOTIFY_PRINT_SERVICES_CHANGED = 2;
    119     private static final int MSG_NOTIFY_PRINT_SERVICE_RECOMMENDATIONS_CHANGED = 3;
    120 
    121     /**
    122      * Package name of print spooler.
    123      *
    124      * @hide
    125      */
    126     public static final String PRINT_SPOOLER_PACKAGE_NAME = "com.android.printspooler";
    127 
    128     /**
    129      * Select enabled services.
    130      * </p>
    131      * @see #getPrintServices
    132      * @hide
    133      */
    134     public static final int ENABLED_SERVICES = 1 << 0;
    135 
    136     /**
    137      * Select disabled services.
    138      * </p>
    139      * @see #getPrintServices
    140      * @hide
    141      */
    142     public static final int DISABLED_SERVICES = 1 << 1;
    143 
    144     /**
    145      * Select all services.
    146      * </p>
    147      * @see #getPrintServices
    148      * @hide
    149      */
    150     public static final int ALL_SERVICES = ENABLED_SERVICES | DISABLED_SERVICES;
    151 
    152     /**
    153      * The action for launching the print dialog activity.
    154      *
    155      * @hide
    156      */
    157     public static final String ACTION_PRINT_DIALOG = "android.print.PRINT_DIALOG";
    158 
    159     /**
    160      * Extra with the intent for starting the print dialog.
    161      * <p>
    162      * <strong>Type:</strong> {@link android.content.IntentSender}
    163      * </p>
    164      *
    165      * @hide
    166      */
    167     public static final String EXTRA_PRINT_DIALOG_INTENT =
    168             "android.print.intent.extra.EXTRA_PRINT_DIALOG_INTENT";
    169 
    170     /**
    171      * Extra with a print job.
    172      * <p>
    173      * <strong>Type:</strong> {@link android.print.PrintJobInfo}
    174      * </p>
    175      *
    176      * @hide
    177      */
    178     public static final String EXTRA_PRINT_JOB =
    179             "android.print.intent.extra.EXTRA_PRINT_JOB";
    180 
    181     /**
    182      * Extra with the print document adapter to be printed.
    183      * <p>
    184      * <strong>Type:</strong> {@link android.print.IPrintDocumentAdapter}
    185      * </p>
    186      *
    187      * @hide
    188      */
    189     public static final String EXTRA_PRINT_DOCUMENT_ADAPTER =
    190             "android.print.intent.extra.EXTRA_PRINT_DOCUMENT_ADAPTER";
    191 
    192     /** @hide */
    193     public static final int APP_ID_ANY = -2;
    194 
    195     private final Context mContext;
    196 
    197     private final IPrintManager mService;
    198 
    199     private final int mUserId;
    200 
    201     private final int mAppId;
    202 
    203     private final Handler mHandler;
    204 
    205     private Map<PrintJobStateChangeListener, PrintJobStateChangeListenerWrapper>
    206             mPrintJobStateChangeListeners;
    207     private Map<PrintServicesChangeListener, PrintServicesChangeListenerWrapper>
    208             mPrintServicesChangeListeners;
    209     private Map<PrintServiceRecommendationsChangeListener,
    210             PrintServiceRecommendationsChangeListenerWrapper>
    211             mPrintServiceRecommendationsChangeListeners;
    212 
    213     /** @hide */
    214     public interface PrintJobStateChangeListener {
    215 
    216         /**
    217          * Callback notifying that a print job state changed.
    218          *
    219          * @param printJobId The print job id.
    220          */
    221         public void onPrintJobStateChanged(PrintJobId printJobId);
    222     }
    223 
    224     /** @hide */
    225     public interface PrintServicesChangeListener {
    226 
    227         /**
    228          * Callback notifying that the print services changed.
    229          */
    230         public void onPrintServicesChanged();
    231     }
    232 
    233     /** @hide */
    234     public interface PrintServiceRecommendationsChangeListener {
    235 
    236         /**
    237          * Callback notifying that the print service recommendations changed.
    238          */
    239         void onPrintServiceRecommendationsChanged();
    240     }
    241 
    242     /**
    243      * Creates a new instance.
    244      *
    245      * @param context The current context in which to operate.
    246      * @param service The backing system service.
    247      * @param userId The user id in which to operate.
    248      * @param appId The application id in which to operate.
    249      * @hide
    250      */
    251     public PrintManager(Context context, IPrintManager service, int userId, int appId) {
    252         mContext = context;
    253         mService = service;
    254         mUserId = userId;
    255         mAppId = appId;
    256         mHandler = new Handler(context.getMainLooper(), null, false) {
    257             @Override
    258             public void handleMessage(Message message) {
    259                 switch (message.what) {
    260                     case MSG_NOTIFY_PRINT_JOB_STATE_CHANGED: {
    261                         SomeArgs args = (SomeArgs) message.obj;
    262                         PrintJobStateChangeListenerWrapper wrapper =
    263                                 (PrintJobStateChangeListenerWrapper) args.arg1;
    264                         PrintJobStateChangeListener listener = wrapper.getListener();
    265                         if (listener != null) {
    266                             PrintJobId printJobId = (PrintJobId) args.arg2;
    267                             listener.onPrintJobStateChanged(printJobId);
    268                         }
    269                         args.recycle();
    270                     } break;
    271                     case MSG_NOTIFY_PRINT_SERVICES_CHANGED: {
    272                         PrintServicesChangeListenerWrapper wrapper =
    273                                 (PrintServicesChangeListenerWrapper) message.obj;
    274                         PrintServicesChangeListener listener = wrapper.getListener();
    275                         if (listener != null) {
    276                             listener.onPrintServicesChanged();
    277                         }
    278                     } break;
    279                     case MSG_NOTIFY_PRINT_SERVICE_RECOMMENDATIONS_CHANGED: {
    280                         PrintServiceRecommendationsChangeListenerWrapper wrapper =
    281                                 (PrintServiceRecommendationsChangeListenerWrapper) message.obj;
    282                         PrintServiceRecommendationsChangeListener listener = wrapper.getListener();
    283                         if (listener != null) {
    284                             listener.onPrintServiceRecommendationsChanged();
    285                         }
    286                     } break;
    287                 }
    288             }
    289         };
    290     }
    291 
    292     /**
    293      * Creates an instance that can access all print jobs.
    294      *
    295      * @param userId The user id for which to get all print jobs.
    296      * @return An instance if the caller has the permission to access all print
    297      *         jobs, null otherwise.
    298      * @hide
    299      */
    300     public PrintManager getGlobalPrintManagerForUser(int userId) {
    301         if (mService == null) {
    302             Log.w(LOG_TAG, "Feature android.software.print not available");
    303             return null;
    304         }
    305         return new PrintManager(mContext, mService, userId, APP_ID_ANY);
    306     }
    307 
    308     PrintJobInfo getPrintJobInfo(PrintJobId printJobId) {
    309         try {
    310             return mService.getPrintJobInfo(printJobId, mAppId, mUserId);
    311         } catch (RemoteException re) {
    312             throw re.rethrowFromSystemServer();
    313         }
    314     }
    315 
    316     /**
    317      * Adds a listener for observing the state of print jobs.
    318      *
    319      * @param listener The listener to add.
    320      * @hide
    321      */
    322     public void addPrintJobStateChangeListener(PrintJobStateChangeListener listener) {
    323         if (mService == null) {
    324             Log.w(LOG_TAG, "Feature android.software.print not available");
    325             return;
    326         }
    327         if (mPrintJobStateChangeListeners == null) {
    328             mPrintJobStateChangeListeners = new ArrayMap<PrintJobStateChangeListener,
    329                     PrintJobStateChangeListenerWrapper>();
    330         }
    331         PrintJobStateChangeListenerWrapper wrappedListener =
    332                 new PrintJobStateChangeListenerWrapper(listener, mHandler);
    333         try {
    334             mService.addPrintJobStateChangeListener(wrappedListener, mAppId, mUserId);
    335             mPrintJobStateChangeListeners.put(listener, wrappedListener);
    336         } catch (RemoteException re) {
    337             throw re.rethrowFromSystemServer();
    338         }
    339     }
    340 
    341     /**
    342      * Removes a listener for observing the state of print jobs.
    343      *
    344      * @param listener The listener to remove.
    345      * @hide
    346      */
    347     public void removePrintJobStateChangeListener(PrintJobStateChangeListener listener) {
    348         if (mService == null) {
    349             Log.w(LOG_TAG, "Feature android.software.print not available");
    350             return;
    351         }
    352         if (mPrintJobStateChangeListeners == null) {
    353             return;
    354         }
    355         PrintJobStateChangeListenerWrapper wrappedListener =
    356                 mPrintJobStateChangeListeners.remove(listener);
    357         if (wrappedListener == null) {
    358             return;
    359         }
    360         if (mPrintJobStateChangeListeners.isEmpty()) {
    361             mPrintJobStateChangeListeners = null;
    362         }
    363         wrappedListener.destroy();
    364         try {
    365             mService.removePrintJobStateChangeListener(wrappedListener, mUserId);
    366         } catch (RemoteException re) {
    367             throw re.rethrowFromSystemServer();
    368         }
    369     }
    370 
    371     /**
    372      * Gets a print job given its id.
    373      *
    374      * @param printJobId The id of the print job.
    375      * @return The print job list.
    376      * @see PrintJob
    377      * @hide
    378      */
    379     public PrintJob getPrintJob(PrintJobId printJobId) {
    380         if (mService == null) {
    381             Log.w(LOG_TAG, "Feature android.software.print not available");
    382             return null;
    383         }
    384         try {
    385             PrintJobInfo printJob = mService.getPrintJobInfo(printJobId, mAppId, mUserId);
    386             if (printJob != null) {
    387                 return new PrintJob(printJob, this);
    388             }
    389         } catch (RemoteException re) {
    390             throw re.rethrowFromSystemServer();
    391         }
    392         return null;
    393     }
    394 
    395     /**
    396      * Get the custom icon for a printer. If the icon is not cached, the icon is
    397      * requested asynchronously. Once it is available the printer is updated.
    398      *
    399      * @param printerId the id of the printer the icon should be loaded for
    400      * @return the custom icon to be used for the printer or null if the icon is
    401      *         not yet available
    402      * @see android.print.PrinterInfo.Builder#setHasCustomPrinterIcon()
    403      * @hide
    404      */
    405     public Icon getCustomPrinterIcon(PrinterId printerId) {
    406         if (mService == null) {
    407             Log.w(LOG_TAG, "Feature android.software.print not available");
    408             return null;
    409         }
    410         try {
    411             return mService.getCustomPrinterIcon(printerId, mUserId);
    412         } catch (RemoteException re) {
    413             throw re.rethrowFromSystemServer();
    414         }
    415     }
    416 
    417     /**
    418      * Gets the print jobs for this application.
    419      *
    420      * @return The print job list.
    421      * @see PrintJob
    422      */
    423     public @NonNull List<PrintJob> getPrintJobs() {
    424         if (mService == null) {
    425             Log.w(LOG_TAG, "Feature android.software.print not available");
    426             return Collections.emptyList();
    427         }
    428         try {
    429             List<PrintJobInfo> printJobInfos = mService.getPrintJobInfos(mAppId, mUserId);
    430             if (printJobInfos == null) {
    431                 return Collections.emptyList();
    432             }
    433             final int printJobCount = printJobInfos.size();
    434             List<PrintJob> printJobs = new ArrayList<PrintJob>(printJobCount);
    435             for (int i = 0; i < printJobCount; i++) {
    436                 printJobs.add(new PrintJob(printJobInfos.get(i), this));
    437             }
    438             return printJobs;
    439         } catch (RemoteException re) {
    440             throw re.rethrowFromSystemServer();
    441         }
    442     }
    443 
    444     void cancelPrintJob(PrintJobId printJobId) {
    445         if (mService == null) {
    446             Log.w(LOG_TAG, "Feature android.software.print not available");
    447             return;
    448         }
    449         try {
    450             mService.cancelPrintJob(printJobId, mAppId, mUserId);
    451         } catch (RemoteException re) {
    452             throw re.rethrowFromSystemServer();
    453         }
    454     }
    455 
    456     void restartPrintJob(PrintJobId printJobId) {
    457         if (mService == null) {
    458             Log.w(LOG_TAG, "Feature android.software.print not available");
    459             return;
    460         }
    461         try {
    462             mService.restartPrintJob(printJobId, mAppId, mUserId);
    463         } catch (RemoteException re) {
    464             throw re.rethrowFromSystemServer();
    465         }
    466     }
    467 
    468     /**
    469      * Creates a print job for printing a {@link PrintDocumentAdapter} with
    470      * default print attributes.
    471      * <p>
    472      * Calling this method brings the print UI allowing the user to customize
    473      * the print job and returns a {@link PrintJob} object without waiting for the
    474      * user to customize or confirm the print job. The returned print job instance
    475      * is in a {@link PrintJobInfo#STATE_CREATED created} state.
    476      * <p>
    477      * This method can be called only from an {@link Activity}. The rationale is that
    478      * printing from a service will create an inconsistent user experience as the print
    479      * UI would appear without any context.
    480      * </p>
    481      * <p>
    482      * Also the passed in {@link PrintDocumentAdapter} will be considered invalid if
    483      * your activity is finished. The rationale is that once the activity that
    484      * initiated printing is finished, the provided adapter may be in an inconsistent
    485      * state as it may depend on the UI presented by the activity.
    486      * </p>
    487      * <p>
    488      * The default print attributes are a hint to the system how the data is to
    489      * be printed. For example, a photo editor may look at the photo aspect ratio
    490      * to determine the default orientation and provide a hint whether the printing
    491      * should be in portrait or landscape. The system will do a best effort to
    492      * selected the hinted options in the print dialog, given the current printer
    493      * supports them.
    494      * </p>
    495      * <p>
    496      * <strong>Note:</strong> Calling this method will bring the print dialog and
    497      * the system will connect to the provided {@link PrintDocumentAdapter}. If a
    498      * configuration change occurs that you application does not handle, for example
    499      * a rotation change, the system will drop the connection to the adapter as the
    500      * activity has to be recreated and the old adapter may be invalid in this context,
    501      * hence a new adapter instance is required. As a consequence, if your activity
    502      * does not handle configuration changes (default behavior), you have to save the
    503      * state that you were printing and call this method again when your activity
    504      * is recreated.
    505      * </p>
    506      *
    507      * @param printJobName A name for the new print job which is shown to the user.
    508      * @param documentAdapter An adapter that emits the document to print.
    509      * @param attributes The default print job attributes or <code>null</code>.
    510      * @return The created print job on success or null on failure.
    511      * @throws IllegalStateException If not called from an {@link Activity}.
    512      * @throws IllegalArgumentException If the print job name is empty or the
    513      * document adapter is null.
    514      *
    515      * @see PrintJob
    516      */
    517     public @NonNull PrintJob print(@NonNull String printJobName,
    518             @NonNull PrintDocumentAdapter documentAdapter,
    519             @Nullable PrintAttributes attributes) {
    520         if (mService == null) {
    521             Log.w(LOG_TAG, "Feature android.software.print not available");
    522             return null;
    523         }
    524         if (!(mContext instanceof Activity)) {
    525             throw new IllegalStateException("Can print only from an activity");
    526         }
    527         if (TextUtils.isEmpty(printJobName)) {
    528             throw new IllegalArgumentException("printJobName cannot be empty");
    529         }
    530         if (documentAdapter == null) {
    531             throw new IllegalArgumentException("documentAdapter cannot be null");
    532         }
    533         PrintDocumentAdapterDelegate delegate = new PrintDocumentAdapterDelegate(
    534                 (Activity) mContext, documentAdapter);
    535         try {
    536             Bundle result = mService.print(printJobName, delegate,
    537                     attributes, mContext.getPackageName(), mAppId, mUserId);
    538             if (result != null) {
    539                 PrintJobInfo printJob = result.getParcelable(EXTRA_PRINT_JOB);
    540                 IntentSender intent = result.getParcelable(EXTRA_PRINT_DIALOG_INTENT);
    541                 if (printJob == null || intent == null) {
    542                     return null;
    543                 }
    544                 try {
    545                     mContext.startIntentSender(intent, null, 0, 0, 0);
    546                     return new PrintJob(printJob, this);
    547                 } catch (SendIntentException sie) {
    548                     Log.e(LOG_TAG, "Couldn't start print job config activity.", sie);
    549                 }
    550             }
    551         } catch (RemoteException re) {
    552             throw re.rethrowFromSystemServer();
    553         }
    554         return null;
    555     }
    556 
    557     /**
    558      * Listen for changes to the installed and enabled print services.
    559      *
    560      * @param listener the listener to add
    561      *
    562      * @see android.print.PrintManager#getPrintServices
    563      */
    564     void addPrintServicesChangeListener(@NonNull PrintServicesChangeListener listener) {
    565         Preconditions.checkNotNull(listener);
    566 
    567         if (mService == null) {
    568             Log.w(LOG_TAG, "Feature android.software.print not available");
    569             return;
    570         }
    571         if (mPrintServicesChangeListeners == null) {
    572             mPrintServicesChangeListeners = new ArrayMap<>();
    573         }
    574         PrintServicesChangeListenerWrapper wrappedListener =
    575                 new PrintServicesChangeListenerWrapper(listener, mHandler);
    576         try {
    577             mService.addPrintServicesChangeListener(wrappedListener, mUserId);
    578             mPrintServicesChangeListeners.put(listener, wrappedListener);
    579         } catch (RemoteException re) {
    580             throw re.rethrowFromSystemServer();
    581         }
    582     }
    583 
    584     /**
    585      * Stop listening for changes to the installed and enabled print services.
    586      *
    587      * @param listener the listener to remove
    588      *
    589      * @see android.print.PrintManager#getPrintServices
    590      */
    591     void removePrintServicesChangeListener(@NonNull PrintServicesChangeListener listener) {
    592         Preconditions.checkNotNull(listener);
    593 
    594         if (mService == null) {
    595             Log.w(LOG_TAG, "Feature android.software.print not available");
    596             return;
    597         }
    598         if (mPrintServicesChangeListeners == null) {
    599             return;
    600         }
    601         PrintServicesChangeListenerWrapper wrappedListener =
    602                 mPrintServicesChangeListeners.remove(listener);
    603         if (wrappedListener == null) {
    604             return;
    605         }
    606         if (mPrintServicesChangeListeners.isEmpty()) {
    607             mPrintServicesChangeListeners = null;
    608         }
    609         wrappedListener.destroy();
    610         try {
    611             mService.removePrintServicesChangeListener(wrappedListener, mUserId);
    612         } catch (RemoteException re) {
    613             Log.e(LOG_TAG, "Error removing print services change listener", re);
    614         }
    615     }
    616 
    617     /**
    618      * Gets the list of print services, but does not register for updates. The user has to register
    619      * for updates by itself, or use {@link PrintServicesLoader}.
    620      *
    621      * @param selectionFlags flags selecting which services to get. Either
    622      *                       {@link #ENABLED_SERVICES},{@link #DISABLED_SERVICES}, or both.
    623      *
    624      * @return The print service list or an empty list.
    625      *
    626      * @see #addPrintServicesChangeListener(PrintServicesChangeListener)
    627      * @see #removePrintServicesChangeListener(PrintServicesChangeListener)
    628      *
    629      * @hide
    630      */
    631     public @NonNull List<PrintServiceInfo> getPrintServices(int selectionFlags) {
    632         Preconditions.checkFlagsArgument(selectionFlags, ALL_SERVICES);
    633 
    634         try {
    635             List<PrintServiceInfo> services = mService.getPrintServices(selectionFlags, mUserId);
    636             if (services != null) {
    637                 return services;
    638             }
    639         } catch (RemoteException re) {
    640             throw re.rethrowFromSystemServer();
    641         }
    642         return Collections.emptyList();
    643     }
    644 
    645     /**
    646      * Listen for changes to the print service recommendations.
    647      *
    648      * @param listener the listener to add
    649      *
    650      * @see android.print.PrintManager#getPrintServiceRecommendations
    651      */
    652     void addPrintServiceRecommendationsChangeListener(
    653             @NonNull PrintServiceRecommendationsChangeListener listener) {
    654         Preconditions.checkNotNull(listener);
    655 
    656         if (mService == null) {
    657             Log.w(LOG_TAG, "Feature android.software.print not available");
    658             return;
    659         }
    660         if (mPrintServiceRecommendationsChangeListeners == null) {
    661             mPrintServiceRecommendationsChangeListeners = new ArrayMap<>();
    662         }
    663         PrintServiceRecommendationsChangeListenerWrapper wrappedListener =
    664                 new PrintServiceRecommendationsChangeListenerWrapper(listener, mHandler);
    665         try {
    666             mService.addPrintServiceRecommendationsChangeListener(wrappedListener, mUserId);
    667             mPrintServiceRecommendationsChangeListeners.put(listener, wrappedListener);
    668         } catch (RemoteException re) {
    669             throw re.rethrowFromSystemServer();
    670         }
    671     }
    672 
    673     /**
    674      * Stop listening for changes to the print service recommendations.
    675      *
    676      * @param listener the listener to remove
    677      *
    678      * @see android.print.PrintManager#getPrintServiceRecommendations
    679      */
    680     void removePrintServiceRecommendationsChangeListener(
    681             @NonNull PrintServiceRecommendationsChangeListener listener) {
    682         Preconditions.checkNotNull(listener);
    683 
    684         if (mService == null) {
    685             Log.w(LOG_TAG, "Feature android.software.print not available");
    686             return;
    687         }
    688         if (mPrintServiceRecommendationsChangeListeners == null) {
    689             return;
    690         }
    691         PrintServiceRecommendationsChangeListenerWrapper wrappedListener =
    692                 mPrintServiceRecommendationsChangeListeners.remove(listener);
    693         if (wrappedListener == null) {
    694             return;
    695         }
    696         if (mPrintServiceRecommendationsChangeListeners.isEmpty()) {
    697             mPrintServiceRecommendationsChangeListeners = null;
    698         }
    699         wrappedListener.destroy();
    700         try {
    701             mService.removePrintServiceRecommendationsChangeListener(wrappedListener, mUserId);
    702         } catch (RemoteException re) {
    703             throw re.rethrowFromSystemServer();
    704         }
    705     }
    706 
    707     /**
    708      * Gets the list of print service recommendations, but does not register for updates. The user
    709      * has to register for updates by itself, or use {@link PrintServiceRecommendationsLoader}.
    710      *
    711      * @return The print service recommendations list or an empty list.
    712      *
    713      * @see #addPrintServiceRecommendationsChangeListener
    714      * @see #removePrintServiceRecommendationsChangeListener
    715      *
    716      * @hide
    717      */
    718     public @NonNull List<RecommendationInfo> getPrintServiceRecommendations() {
    719         try {
    720             List<RecommendationInfo> recommendations =
    721                     mService.getPrintServiceRecommendations(mUserId);
    722             if (recommendations != null) {
    723                 return recommendations;
    724             }
    725         } catch (RemoteException re) {
    726             throw re.rethrowFromSystemServer();
    727         }
    728         return Collections.emptyList();
    729     }
    730 
    731     /**
    732      * @hide
    733      */
    734     public PrinterDiscoverySession createPrinterDiscoverySession() {
    735         if (mService == null) {
    736             Log.w(LOG_TAG, "Feature android.software.print not available");
    737             return null;
    738         }
    739         return new PrinterDiscoverySession(mService, mContext, mUserId);
    740     }
    741 
    742     /**
    743      * Enable or disable a print service.
    744      *
    745      * @param service The service to enabled or disable
    746      * @param isEnabled whether the service should be enabled or disabled
    747      *
    748      * @hide
    749      */
    750     public void setPrintServiceEnabled(@NonNull ComponentName service, boolean isEnabled) {
    751         if (mService == null) {
    752             Log.w(LOG_TAG, "Feature android.software.print not available");
    753             return;
    754         }
    755         try {
    756             mService.setPrintServiceEnabled(service, isEnabled, mUserId);
    757         } catch (RemoteException re) {
    758             Log.e(LOG_TAG, "Error enabling or disabling " + service, re);
    759         }
    760     }
    761 
    762     /**
    763      * @hide
    764      */
    765     public static final class PrintDocumentAdapterDelegate extends IPrintDocumentAdapter.Stub
    766             implements ActivityLifecycleCallbacks {
    767         private final Object mLock = new Object();
    768 
    769         private Activity mActivity; // Strong reference OK - cleared in destroy
    770 
    771         private PrintDocumentAdapter mDocumentAdapter; // Strong reference OK - cleared in destroy
    772 
    773         private Handler mHandler; // Strong reference OK - cleared in destroy
    774 
    775         private IPrintDocumentAdapterObserver mObserver; // Strong reference OK - cleared in destroy
    776 
    777         private DestroyableCallback mPendingCallback;
    778 
    779         public PrintDocumentAdapterDelegate(Activity activity,
    780                 PrintDocumentAdapter documentAdapter) {
    781             if (activity.isFinishing()) {
    782                 // The activity is already dead hence the onActivityDestroyed callback won't be
    783                 // triggered. Hence it is not save to print in this situation.
    784                 throw new IllegalStateException("Cannot start printing for finishing activity");
    785             }
    786 
    787             mActivity = activity;
    788             mDocumentAdapter = documentAdapter;
    789             mHandler = new MyHandler(mActivity.getMainLooper());
    790             mActivity.getApplication().registerActivityLifecycleCallbacks(this);
    791         }
    792 
    793         @Override
    794         public void setObserver(IPrintDocumentAdapterObserver observer) {
    795             final boolean destroyed;
    796             synchronized (mLock) {
    797                 mObserver = observer;
    798                 destroyed = isDestroyedLocked();
    799             }
    800 
    801             if (destroyed && observer != null) {
    802                 try {
    803                     observer.onDestroy();
    804                 } catch (RemoteException re) {
    805                     Log.e(LOG_TAG, "Error announcing destroyed state", re);
    806                 }
    807             }
    808         }
    809 
    810         @Override
    811         public void start() {
    812             synchronized (mLock) {
    813                 // If destroyed the handler is null.
    814                 if (!isDestroyedLocked()) {
    815                     mHandler.obtainMessage(MyHandler.MSG_ON_START,
    816                             mDocumentAdapter).sendToTarget();
    817                 }
    818             }
    819         }
    820 
    821         @Override
    822         public void layout(PrintAttributes oldAttributes, PrintAttributes newAttributes,
    823                 ILayoutResultCallback callback, Bundle metadata, int sequence) {
    824 
    825             ICancellationSignal cancellationTransport = CancellationSignal.createTransport();
    826             try {
    827                 callback.onLayoutStarted(cancellationTransport, sequence);
    828             } catch (RemoteException re) {
    829                 // The spooler is dead - can't recover.
    830                 Log.e(LOG_TAG, "Error notifying for layout start", re);
    831                 return;
    832             }
    833 
    834             synchronized (mLock) {
    835                 // If destroyed the handler is null.
    836                 if (isDestroyedLocked()) {
    837                     return;
    838                 }
    839 
    840                 CancellationSignal cancellationSignal = CancellationSignal.fromTransport(
    841                         cancellationTransport);
    842 
    843                 SomeArgs args = SomeArgs.obtain();
    844                 args.arg1 = mDocumentAdapter;
    845                 args.arg2 = oldAttributes;
    846                 args.arg3 = newAttributes;
    847                 args.arg4 = cancellationSignal;
    848                 args.arg5 = new MyLayoutResultCallback(callback, sequence);
    849                 args.arg6 = metadata;
    850 
    851                 mHandler.obtainMessage(MyHandler.MSG_ON_LAYOUT, args).sendToTarget();
    852             }
    853         }
    854 
    855         @Override
    856         public void write(PageRange[] pages, ParcelFileDescriptor fd,
    857                 IWriteResultCallback callback, int sequence) {
    858 
    859             ICancellationSignal cancellationTransport = CancellationSignal.createTransport();
    860             try {
    861                 callback.onWriteStarted(cancellationTransport, sequence);
    862             } catch (RemoteException re) {
    863                 // The spooler is dead - can't recover.
    864                 Log.e(LOG_TAG, "Error notifying for write start", re);
    865                 return;
    866             }
    867 
    868             synchronized (mLock) {
    869                 // If destroyed the handler is null.
    870                 if (isDestroyedLocked()) {
    871                     return;
    872                 }
    873 
    874                 CancellationSignal cancellationSignal = CancellationSignal.fromTransport(
    875                         cancellationTransport);
    876 
    877                 SomeArgs args = SomeArgs.obtain();
    878                 args.arg1 = mDocumentAdapter;
    879                 args.arg2 = pages;
    880                 args.arg3 = fd;
    881                 args.arg4 = cancellationSignal;
    882                 args.arg5 = new MyWriteResultCallback(callback, fd, sequence);
    883 
    884                 mHandler.obtainMessage(MyHandler.MSG_ON_WRITE, args).sendToTarget();
    885             }
    886         }
    887 
    888         @Override
    889         public void finish() {
    890             synchronized (mLock) {
    891                 // If destroyed the handler is null.
    892                 if (!isDestroyedLocked()) {
    893                     mHandler.obtainMessage(MyHandler.MSG_ON_FINISH,
    894                             mDocumentAdapter).sendToTarget();
    895                 }
    896             }
    897         }
    898 
    899         @Override
    900         public void kill(String reason) {
    901             synchronized (mLock) {
    902                 // If destroyed the handler is null.
    903                 if (!isDestroyedLocked()) {
    904                     mHandler.obtainMessage(MyHandler.MSG_ON_KILL,
    905                             reason).sendToTarget();
    906                 }
    907             }
    908         }
    909 
    910         @Override
    911         public void onActivityPaused(Activity activity) {
    912             /* do nothing */
    913         }
    914 
    915         @Override
    916         public void onActivityCreated(Activity activity, Bundle savedInstanceState) {
    917             /* do nothing */
    918         }
    919 
    920         @Override
    921         public void onActivityStarted(Activity activity) {
    922             /* do nothing */
    923         }
    924 
    925         @Override
    926         public void onActivityResumed(Activity activity) {
    927             /* do nothing */
    928         }
    929 
    930         @Override
    931         public void onActivityStopped(Activity activity) {
    932             /* do nothing */
    933         }
    934 
    935         @Override
    936         public void onActivitySaveInstanceState(Activity activity, Bundle outState) {
    937             /* do nothing */
    938         }
    939 
    940         @Override
    941         public void onActivityDestroyed(Activity activity) {
    942             // We really care only if the activity is being destroyed to
    943             // notify the the print spooler so it can close the print dialog.
    944             // Note the the spooler has a death recipient that observes if
    945             // this process gets killed so we cover the case of onDestroy not
    946             // being called due to this process being killed to reclaim memory.
    947             IPrintDocumentAdapterObserver observer = null;
    948             synchronized (mLock) {
    949                 if (activity == mActivity) {
    950                     observer = mObserver;
    951                     destroyLocked();
    952                 }
    953             }
    954             if (observer != null) {
    955                 try {
    956                     observer.onDestroy();
    957                 } catch (RemoteException re) {
    958                     Log.e(LOG_TAG, "Error announcing destroyed state", re);
    959                 }
    960             }
    961         }
    962 
    963         private boolean isDestroyedLocked() {
    964             return (mActivity == null);
    965         }
    966 
    967         private void destroyLocked() {
    968             mActivity.getApplication().unregisterActivityLifecycleCallbacks(
    969                     PrintDocumentAdapterDelegate.this);
    970             mActivity = null;
    971 
    972             mDocumentAdapter = null;
    973 
    974             // This method is only called from the main thread, so
    975             // clearing the messages guarantees that any time a
    976             // message is handled we are not in a destroyed state.
    977             mHandler.removeMessages(MyHandler.MSG_ON_START);
    978             mHandler.removeMessages(MyHandler.MSG_ON_LAYOUT);
    979             mHandler.removeMessages(MyHandler.MSG_ON_WRITE);
    980             mHandler.removeMessages(MyHandler.MSG_ON_FINISH);
    981             mHandler = null;
    982 
    983             mObserver = null;
    984 
    985             if (mPendingCallback != null) {
    986                 mPendingCallback.destroy();
    987                 mPendingCallback = null;
    988             }
    989         }
    990 
    991         private final class MyHandler extends Handler {
    992             public static final int MSG_ON_START = 1;
    993             public static final int MSG_ON_LAYOUT = 2;
    994             public static final int MSG_ON_WRITE = 3;
    995             public static final int MSG_ON_FINISH = 4;
    996             public static final int MSG_ON_KILL = 5;
    997 
    998             public MyHandler(Looper looper) {
    999                 super(looper, null, true);
   1000             }
   1001 
   1002             @Override
   1003             public void handleMessage(Message message) {
   1004                 switch (message.what) {
   1005                     case MSG_ON_START: {
   1006                         if (DEBUG) {
   1007                             Log.i(LOG_TAG, "onStart()");
   1008                         }
   1009 
   1010                         ((PrintDocumentAdapter) message.obj).onStart();
   1011                     } break;
   1012 
   1013                     case MSG_ON_LAYOUT: {
   1014                         SomeArgs args = (SomeArgs) message.obj;
   1015                         PrintDocumentAdapter adapter = (PrintDocumentAdapter) args.arg1;
   1016                         PrintAttributes oldAttributes = (PrintAttributes) args.arg2;
   1017                         PrintAttributes newAttributes = (PrintAttributes) args.arg3;
   1018                         CancellationSignal cancellation = (CancellationSignal) args.arg4;
   1019                         LayoutResultCallback callback = (LayoutResultCallback) args.arg5;
   1020                         Bundle metadata = (Bundle) args.arg6;
   1021                         args.recycle();
   1022 
   1023                         if (DEBUG) {
   1024                             StringBuilder builder = new StringBuilder();
   1025                             builder.append("PrintDocumentAdapter#onLayout() {\n");
   1026                             builder.append("\n  oldAttributes:").append(oldAttributes);
   1027                             builder.append("\n  newAttributes:").append(newAttributes);
   1028                             builder.append("\n  preview:").append(metadata.getBoolean(
   1029                                     PrintDocumentAdapter.EXTRA_PRINT_PREVIEW));
   1030                             builder.append("\n}");
   1031                             Log.i(LOG_TAG, builder.toString());
   1032                         }
   1033 
   1034                         adapter.onLayout(oldAttributes, newAttributes, cancellation,
   1035                                 callback, metadata);
   1036                     } break;
   1037 
   1038                     case MSG_ON_WRITE: {
   1039                         SomeArgs args = (SomeArgs) message.obj;
   1040                         PrintDocumentAdapter adapter = (PrintDocumentAdapter) args.arg1;
   1041                         PageRange[] pages = (PageRange[]) args.arg2;
   1042                         ParcelFileDescriptor fd = (ParcelFileDescriptor) args.arg3;
   1043                         CancellationSignal cancellation = (CancellationSignal) args.arg4;
   1044                         WriteResultCallback callback = (WriteResultCallback) args.arg5;
   1045                         args.recycle();
   1046 
   1047                         if (DEBUG) {
   1048                             StringBuilder builder = new StringBuilder();
   1049                             builder.append("PrintDocumentAdapter#onWrite() {\n");
   1050                             builder.append("\n  pages:").append(Arrays.toString(pages));
   1051                             builder.append("\n}");
   1052                             Log.i(LOG_TAG, builder.toString());
   1053                         }
   1054 
   1055                         adapter.onWrite(pages, fd, cancellation, callback);
   1056                     } break;
   1057 
   1058                     case MSG_ON_FINISH: {
   1059                         if (DEBUG) {
   1060                             Log.i(LOG_TAG, "onFinish()");
   1061                         }
   1062 
   1063                         ((PrintDocumentAdapter) message.obj).onFinish();
   1064 
   1065                         // Done printing, so destroy this instance as it
   1066                         // should not be used anymore.
   1067                         synchronized (mLock) {
   1068                             destroyLocked();
   1069                         }
   1070                     } break;
   1071 
   1072                     case MSG_ON_KILL: {
   1073                         if (DEBUG) {
   1074                             Log.i(LOG_TAG, "onKill()");
   1075                         }
   1076 
   1077                         String reason = (String) message.obj;
   1078                         throw new RuntimeException(reason);
   1079                     }
   1080 
   1081                     default: {
   1082                         throw new IllegalArgumentException("Unknown message: "
   1083                                 + message.what);
   1084                     }
   1085                 }
   1086             }
   1087         }
   1088 
   1089         private interface DestroyableCallback {
   1090             public void destroy();
   1091         }
   1092 
   1093         private final class MyLayoutResultCallback extends LayoutResultCallback
   1094                 implements DestroyableCallback {
   1095             private ILayoutResultCallback mCallback;
   1096             private final int mSequence;
   1097 
   1098             public MyLayoutResultCallback(ILayoutResultCallback callback,
   1099                     int sequence) {
   1100                 mCallback = callback;
   1101                 mSequence = sequence;
   1102             }
   1103 
   1104             @Override
   1105             public void onLayoutFinished(PrintDocumentInfo info, boolean changed) {
   1106                 final ILayoutResultCallback callback;
   1107                 synchronized (mLock) {
   1108                     callback = mCallback;
   1109                 }
   1110 
   1111                 // If the callback is null we are destroyed.
   1112                 if (callback == null) {
   1113                     Log.e(LOG_TAG, "PrintDocumentAdapter is destroyed. Did you "
   1114                             + "finish the printing activity before print completion "
   1115                             + "or did you invoke a callback after finish?");
   1116                     return;
   1117                 }
   1118 
   1119                 try {
   1120                     if (info == null) {
   1121                         throw new NullPointerException("document info cannot be null");
   1122                     }
   1123 
   1124                     try {
   1125                         callback.onLayoutFinished(info, changed, mSequence);
   1126                     } catch (RemoteException re) {
   1127                         Log.e(LOG_TAG, "Error calling onLayoutFinished", re);
   1128                     }
   1129                 } finally {
   1130                     destroy();
   1131                 }
   1132             }
   1133 
   1134             @Override
   1135             public void onLayoutFailed(CharSequence error) {
   1136                 final ILayoutResultCallback callback;
   1137                 synchronized (mLock) {
   1138                     callback = mCallback;
   1139                 }
   1140 
   1141                 // If the callback is null we are destroyed.
   1142                 if (callback == null) {
   1143                     Log.e(LOG_TAG, "PrintDocumentAdapter is destroyed. Did you "
   1144                             + "finish the printing activity before print completion "
   1145                             + "or did you invoke a callback after finish?");
   1146                     return;
   1147                 }
   1148 
   1149                 try {
   1150                     callback.onLayoutFailed(error, mSequence);
   1151                 } catch (RemoteException re) {
   1152                     Log.e(LOG_TAG, "Error calling onLayoutFailed", re);
   1153                 } finally {
   1154                     destroy();
   1155                 }
   1156             }
   1157 
   1158             @Override
   1159             public void onLayoutCancelled() {
   1160                 final ILayoutResultCallback callback;
   1161                 synchronized (mLock) {
   1162                     callback = mCallback;
   1163                 }
   1164 
   1165                 // If the callback is null we are destroyed.
   1166                 if (callback == null) {
   1167                     Log.e(LOG_TAG, "PrintDocumentAdapter is destroyed. Did you "
   1168                             + "finish the printing activity before print completion "
   1169                             + "or did you invoke a callback after finish?");
   1170                     return;
   1171                 }
   1172 
   1173                 try {
   1174                     callback.onLayoutCanceled(mSequence);
   1175                 } catch (RemoteException re) {
   1176                     Log.e(LOG_TAG, "Error calling onLayoutFailed", re);
   1177                 } finally {
   1178                     destroy();
   1179                 }
   1180             }
   1181 
   1182             @Override
   1183             public void destroy() {
   1184                 synchronized (mLock) {
   1185                     mCallback = null;
   1186                     mPendingCallback = null;
   1187                 }
   1188             }
   1189         }
   1190 
   1191         private final class MyWriteResultCallback extends WriteResultCallback
   1192                 implements DestroyableCallback {
   1193             private ParcelFileDescriptor mFd;
   1194             private IWriteResultCallback mCallback;
   1195             private final int mSequence;
   1196 
   1197             public MyWriteResultCallback(IWriteResultCallback callback,
   1198                     ParcelFileDescriptor fd, int sequence) {
   1199                 mFd = fd;
   1200                 mSequence = sequence;
   1201                 mCallback = callback;
   1202             }
   1203 
   1204             @Override
   1205             public void onWriteFinished(PageRange[] pages) {
   1206                 final IWriteResultCallback callback;
   1207                 synchronized (mLock) {
   1208                     callback = mCallback;
   1209                 }
   1210 
   1211                 // If the callback is null we are destroyed.
   1212                 if (callback == null) {
   1213                     Log.e(LOG_TAG, "PrintDocumentAdapter is destroyed. Did you "
   1214                             + "finish the printing activity before print completion "
   1215                             + "or did you invoke a callback after finish?");
   1216                     return;
   1217                 }
   1218 
   1219                 try {
   1220                     if (pages == null) {
   1221                         throw new IllegalArgumentException("pages cannot be null");
   1222                     }
   1223                     if (pages.length == 0) {
   1224                         throw new IllegalArgumentException("pages cannot be empty");
   1225                     }
   1226 
   1227                     try {
   1228                         callback.onWriteFinished(pages, mSequence);
   1229                     } catch (RemoteException re) {
   1230                         Log.e(LOG_TAG, "Error calling onWriteFinished", re);
   1231                     }
   1232                 } finally {
   1233                     destroy();
   1234                 }
   1235             }
   1236 
   1237             @Override
   1238             public void onWriteFailed(CharSequence error) {
   1239                 final IWriteResultCallback callback;
   1240                 synchronized (mLock) {
   1241                     callback = mCallback;
   1242                 }
   1243 
   1244                 // If the callback is null we are destroyed.
   1245                 if (callback == null) {
   1246                     Log.e(LOG_TAG, "PrintDocumentAdapter is destroyed. Did you "
   1247                             + "finish the printing activity before print completion "
   1248                             + "or did you invoke a callback after finish?");
   1249                     return;
   1250                 }
   1251 
   1252                 try {
   1253                     callback.onWriteFailed(error, mSequence);
   1254                 } catch (RemoteException re) {
   1255                     Log.e(LOG_TAG, "Error calling onWriteFailed", re);
   1256                 } finally {
   1257                     destroy();
   1258                 }
   1259             }
   1260 
   1261             @Override
   1262             public void onWriteCancelled() {
   1263                 final IWriteResultCallback callback;
   1264                 synchronized (mLock) {
   1265                     callback = mCallback;
   1266                 }
   1267 
   1268                 // If the callback is null we are destroyed.
   1269                 if (callback == null) {
   1270                     Log.e(LOG_TAG, "PrintDocumentAdapter is destroyed. Did you "
   1271                             + "finish the printing activity before print completion "
   1272                             + "or did you invoke a callback after finish?");
   1273                     return;
   1274                 }
   1275 
   1276                 try {
   1277                     callback.onWriteCanceled(mSequence);
   1278                 } catch (RemoteException re) {
   1279                     Log.e(LOG_TAG, "Error calling onWriteCanceled", re);
   1280                 } finally {
   1281                     destroy();
   1282                 }
   1283             }
   1284 
   1285             @Override
   1286             public void destroy() {
   1287                 synchronized (mLock) {
   1288                     IoUtils.closeQuietly(mFd);
   1289                     mCallback = null;
   1290                     mFd = null;
   1291                     mPendingCallback = null;
   1292                 }
   1293             }
   1294         }
   1295     }
   1296 
   1297     /**
   1298      * @hide
   1299      */
   1300     public static final class PrintJobStateChangeListenerWrapper extends
   1301             IPrintJobStateChangeListener.Stub {
   1302         private final WeakReference<PrintJobStateChangeListener> mWeakListener;
   1303         private final WeakReference<Handler> mWeakHandler;
   1304 
   1305         public PrintJobStateChangeListenerWrapper(PrintJobStateChangeListener listener,
   1306                 Handler handler) {
   1307             mWeakListener = new WeakReference<PrintJobStateChangeListener>(listener);
   1308             mWeakHandler = new WeakReference<Handler>(handler);
   1309         }
   1310 
   1311         @Override
   1312         public void onPrintJobStateChanged(PrintJobId printJobId) {
   1313             Handler handler = mWeakHandler.get();
   1314             PrintJobStateChangeListener listener = mWeakListener.get();
   1315             if (handler != null && listener != null) {
   1316                 SomeArgs args = SomeArgs.obtain();
   1317                 args.arg1 = this;
   1318                 args.arg2 = printJobId;
   1319                 handler.obtainMessage(MSG_NOTIFY_PRINT_JOB_STATE_CHANGED,
   1320                         args).sendToTarget();
   1321             }
   1322         }
   1323 
   1324         public void destroy() {
   1325             mWeakListener.clear();
   1326         }
   1327 
   1328         public PrintJobStateChangeListener getListener() {
   1329             return mWeakListener.get();
   1330         }
   1331     }
   1332 
   1333     /**
   1334      * @hide
   1335      */
   1336     public static final class PrintServicesChangeListenerWrapper extends
   1337             IPrintServicesChangeListener.Stub {
   1338         private final WeakReference<PrintServicesChangeListener> mWeakListener;
   1339         private final WeakReference<Handler> mWeakHandler;
   1340 
   1341         public PrintServicesChangeListenerWrapper(PrintServicesChangeListener listener,
   1342                 Handler handler) {
   1343             mWeakListener = new WeakReference<>(listener);
   1344             mWeakHandler = new WeakReference<>(handler);
   1345         }
   1346 
   1347         @Override
   1348         public void onPrintServicesChanged() {
   1349             Handler handler = mWeakHandler.get();
   1350             PrintServicesChangeListener listener = mWeakListener.get();
   1351             if (handler != null && listener != null) {
   1352                 handler.obtainMessage(MSG_NOTIFY_PRINT_SERVICES_CHANGED, this).sendToTarget();
   1353             }
   1354         }
   1355 
   1356         public void destroy() {
   1357             mWeakListener.clear();
   1358         }
   1359 
   1360         public PrintServicesChangeListener getListener() {
   1361             return mWeakListener.get();
   1362         }
   1363     }
   1364 
   1365     /**
   1366      * @hide
   1367      */
   1368     public static final class PrintServiceRecommendationsChangeListenerWrapper extends
   1369             IRecommendationsChangeListener.Stub {
   1370         private final WeakReference<PrintServiceRecommendationsChangeListener> mWeakListener;
   1371         private final WeakReference<Handler> mWeakHandler;
   1372 
   1373         public PrintServiceRecommendationsChangeListenerWrapper(
   1374                 PrintServiceRecommendationsChangeListener listener, Handler handler) {
   1375             mWeakListener = new WeakReference<>(listener);
   1376             mWeakHandler = new WeakReference<>(handler);
   1377         }
   1378 
   1379         @Override
   1380         public void onRecommendationsChanged() {
   1381             Handler handler = mWeakHandler.get();
   1382             PrintServiceRecommendationsChangeListener listener = mWeakListener.get();
   1383             if (handler != null && listener != null) {
   1384                 handler.obtainMessage(MSG_NOTIFY_PRINT_SERVICE_RECOMMENDATIONS_CHANGED,
   1385                         this).sendToTarget();
   1386             }
   1387         }
   1388 
   1389         public void destroy() {
   1390             mWeakListener.clear();
   1391         }
   1392 
   1393         public PrintServiceRecommendationsChangeListener getListener() {
   1394             return mWeakListener.get();
   1395         }
   1396     }
   1397 }
   1398