| /* |
| * Copyright (C) 2015 The Android Open Source Project |
| * |
| * 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 com.android.printspooler.util; |
| |
| import android.content.ComponentName; |
| import android.content.Context; |
| import android.content.SharedPreferences; |
| import android.content.SharedPreferences.OnSharedPreferenceChangeListener; |
| import android.printservice.PrintService; |
| import android.util.ArraySet; |
| |
| import java.util.List; |
| import java.util.Set; |
| |
| /** |
| * Manage approved print services. These services are stored in the shared preferences. |
| */ |
| public class ApprovedPrintServices { |
| /** |
| * Used for locking accesses to the approved services. |
| */ |
| static final public Object sLock = new Object(); |
| |
| private static final String APPROVED_SERVICES_PREFERENCE = "PRINT_SPOOLER_APPROVED_SERVICES"; |
| private final SharedPreferences mPreferences; |
| |
| /** |
| * Create a new {@link ApprovedPrintServices} |
| * |
| * @param owner The {@link Context} using this object. |
| */ |
| public ApprovedPrintServices(Context owner) { |
| mPreferences = owner.getSharedPreferences(APPROVED_SERVICES_PREFERENCE, |
| Context.MODE_PRIVATE); |
| } |
| |
| /** |
| * Get {@link Set} of approved services. |
| * |
| * @return A {@link Set} containing all currently approved services. |
| */ |
| public Set<String> getApprovedServices() { |
| return mPreferences.getStringSet(APPROVED_SERVICES_PREFERENCE, null); |
| } |
| |
| /** |
| * Check if a {@link PrintService} is approved. |
| * |
| * This function does not acquire the {@link #sLock}. |
| * |
| * @param service The {@link ComponentName} of the {@link PrintService} that might be approved |
| * @return true iff the service is currently approved |
| */ |
| public boolean isApprovedService(ComponentName service) { |
| final Set<String> approvedServices = getApprovedServices(); |
| |
| if (approvedServices != null) { |
| final String flattenedString = service.flattenToShortString(); |
| |
| for (String approvedService : approvedServices) { |
| if (approvedService.equals(flattenedString)) { |
| return true; |
| } |
| } |
| } |
| |
| return false; |
| } |
| |
| /** |
| * Add a {@link PrintService} to the list of approved print services. |
| * |
| * @param serviceToAdd The {@link ComponentName} of the {@link PrintService} to be approved. |
| */ |
| public void addApprovedService(ComponentName serviceToAdd) { |
| synchronized (sLock) { |
| Set<String> oldApprovedServices = |
| mPreferences.getStringSet(APPROVED_SERVICES_PREFERENCE, null); |
| |
| Set<String> newApprovedServices; |
| if (oldApprovedServices == null) { |
| newApprovedServices = new ArraySet<String>(1); |
| } else { |
| // Copy approved services. |
| newApprovedServices = new ArraySet<String>(oldApprovedServices); |
| } |
| newApprovedServices.add(serviceToAdd.flattenToShortString()); |
| |
| SharedPreferences.Editor editor = mPreferences.edit(); |
| editor.putStringSet(APPROVED_SERVICES_PREFERENCE, newApprovedServices); |
| editor.apply(); |
| } |
| } |
| |
| /** |
| * Add a {@link OnSharedPreferenceChangeListener} that listens for changes to the approved |
| * services. Should only be called while holding {@link #sLock} to synchronize against |
| * {@link #addApprovedService}. |
| * |
| * @param listener {@link OnSharedPreferenceChangeListener} to register |
| */ |
| public void registerChangeListenerLocked(OnSharedPreferenceChangeListener listener) { |
| mPreferences.registerOnSharedPreferenceChangeListener(listener); |
| } |
| |
| /** |
| * Unregister a listener registered in {@link #registerChangeListenerLocked}. |
| * |
| * @param listener {@link OnSharedPreferenceChangeListener} to unregister |
| */ |
| public void unregisterChangeListener(OnSharedPreferenceChangeListener listener) { |
| mPreferences.unregisterOnSharedPreferenceChangeListener(listener); |
| } |
| |
| /** |
| * Remove all approved {@link PrintService print services} that are not in the given set. |
| * |
| * @param serviceNamesToKeep The {@link ComponentName names } of the services to keep |
| */ |
| public void pruneApprovedServices(List<ComponentName> serviceNamesToKeep) { |
| synchronized (sLock) { |
| Set<String> approvedServices = getApprovedServices(); |
| |
| if (approvedServices == null) { |
| return; |
| } |
| |
| Set<String> newApprovedServices = new ArraySet<>(approvedServices.size()); |
| |
| final int numServiceNamesToKeep = serviceNamesToKeep.size(); |
| for(int i = 0; i < numServiceNamesToKeep; i++) { |
| String serviceToKeep = serviceNamesToKeep.get(i).flattenToShortString(); |
| if (approvedServices.contains(serviceToKeep)) { |
| newApprovedServices.add(serviceToKeep); |
| } |
| } |
| |
| if (approvedServices.size() != newApprovedServices.size()) { |
| SharedPreferences.Editor editor = mPreferences.edit(); |
| |
| editor.putStringSet(APPROVED_SERVICES_PREFERENCE, newApprovedServices); |
| editor.apply(); |
| } |
| } |
| } |
| } |