Home | History | Annotate | Download | only in recommendation 
      1 /*
      2  * Copyright (C) 2016 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 com.android.printservice.recommendation;
     18 
     19 import android.annotation.NonNull;
     20 import android.annotation.Nullable;
     21 import android.annotation.StringRes;
     22 
     23 import java.net.InetAddress;
     24 import java.util.List;
     25 
     26 /**
     27  * Interface to be implemented by each print service plugin.
     28  * <p/>
     29  * A print service plugin is a minimal version of a real {@link android.printservice.PrintService
     30  * print service}. You cannot print using the plugin. The only functionality in the plugin is to
     31  * report the number of printers that the real service would discover.
     32  */
     33 public interface PrintServicePlugin {
     34     /**
     35      * Call back used by the print service plugins.
     36      */
     37     interface PrinterDiscoveryCallback {
     38         /**
     39          * Announce that something changed and the UI for this plugin should be updated.
     40          *
     41          * @param discoveredPrinters The printers discovered.
     42          */
     43         void onChanged(@Nullable List<InetAddress> discoveredPrinters);
     44     }
     45 
     46     /**
     47      * Get the name (a string reference) of the {@link android.printservice.PrintService print
     48      * service} with the {@link #getPackageName specified package name}. This is read once, hence
     49      * returning different data at different times is not allowed.
     50      *
     51      * @return The name of the print service as a string reference. The localization is handled
     52      *         outside of the plugin.
     53      */
     54     @StringRes int getName();
     55 
     56     /**
     57      * The package name of the full print service.
     58      *
     59      * @return The package name
     60      */
     61     @NonNull CharSequence getPackageName();
     62 
     63     /**
     64      * Start the discovery plugin.
     65      *
     66      * @param callback Callbacks used by this plugin.
     67      *
     68      * @throws Exception If anything went wrong when starting the plugin
     69      */
     70     void start(@NonNull PrinterDiscoveryCallback callback) throws Exception;
     71 
     72     /**
     73      * Stop the plugin. This can only return once the plugin is completely finished and cleaned up.
     74      *
     75      * @throws Exception If anything went wrong while stopping plugin
     76      */
     77     void stop() throws Exception;
     78 }
     79