Introduce UUIDMap for storing objects that are keyed by a UUID

This patch introduces the new ``UUIDMap`` type, reducing code duplication and
making UUID lookups faster. We currently already use UUIDs as the identifier for
the ``DatabaseEntry`` and ``Slot`` types, but the way lookups by UUID work are
kind of ugly, as we simply iterate over the list until we find a match. As we're
probably going to have more types like this soon (groups and icons, for
example), I figured it'd be good to abstract this away into a separate type and
make it a map instead of a list.

The only thing that has gotten slower is the ``swap`` method. The internal
``LinkedHashMap`` retains insertion order with a linked list, but does not know
about the position of the values, so we basically have to copy the entire map to
simply swap two values. I don't think it's too big of a deal, because swap
operations still take less than a millisecond even with large vaults, but
suggestions for improving this are welcome.

I had to update gradle and JUnit to be able to use the new ``assertThrows``
assertion method, so this patch includes that as well.

app/build.gradle

@@ -10,6 +10,13 @@ android {
         versionCode 14
         versionName "0.4.3"
     }
+
+    testOptions {
+        unitTests.all {
+            useJUnitPlatform()
+        }
+    }
+
     buildTypes {
         debug {
             minifyEnabled false
@@ -24,6 +31,7 @@ android {
             resValue "bool", "pref_secure_screen_default", "true"
         }
     }
+
     compileOptions {
         targetCompatibility 1.8
         sourceCompatibility 1.8
@@ -57,5 +65,6 @@ dependencies {
     }
     annotationProcessor 'androidx.annotation:annotation:1.1.0'
     annotationProcessor 'com.github.bumptech.glide:compiler:4.9.0'
-    testImplementation 'junit:junit:4.12'
+    testRuntimeOnly 'org.junit.jupiter:junit-jupiter-engine:5.4.2'
+    testImplementation 'org.junit.jupiter:junit-jupiter-api:5.4.2'
 }

app/src/main/java/com/beemdevelopment/aegis/db/Database.java

@@ -2,17 +2,15 @@ package com.beemdevelopment.aegis.db;
 
 import com.beemdevelopment.aegis.encoding.Base64Exception;
 import com.beemdevelopment.aegis.otp.OtpInfoException;
+import com.beemdevelopment.aegis.util.UUIDMap;
 
 import org.json.JSONArray;
 import org.json.JSONException;
 import org.json.JSONObject;
 
-import java.util.List;
-import java.util.UUID;
-
 public class Database {
     private static final int VERSION = 1;
-    private DatabaseEntryList _entries = new DatabaseEntryList();
+    private UUIDMap<DatabaseEntry> _entries = new UUIDMap<>();
 
     public JSONObject toJson() {
         try {
@@ -32,6 +30,7 @@ public class Database {
 
     public static Database fromJson(JSONObject obj) throws DatabaseException {
         Database db = new Database();
+        UUIDMap<DatabaseEntry> entries = db.getEntries();
 
         try {
             int ver = obj.getInt("version");
@@ -42,7 +41,7 @@ public class Database {
             JSONArray array = obj.getJSONArray("entries");
             for (int i = 0; i < array.length(); i++) {
                 DatabaseEntry entry = DatabaseEntry.fromJson(array.getJSONObject(i));
-                db.addEntry(entry);
+                entries.add(entry);
             }
         } catch (Base64Exception | OtpInfoException | JSONException e) {
             throw new DatabaseException(e);
@@ -51,27 +50,7 @@ public class Database {
         return db;
     }
 
-    public void addEntry(DatabaseEntry entry) {
-        _entries.add(entry);
-    }
-
-    public void removeEntry(DatabaseEntry entry) {
-        _entries.remove(entry);
-    }
-
-    public void replaceEntry(DatabaseEntry newEntry) {
-        _entries.replace(newEntry);
-    }
-
-    public void swapEntries(DatabaseEntry entry1, DatabaseEntry entry2) {
-        _entries.swap(entry1, entry2);
-    }
-
-    public List<DatabaseEntry> getEntries() {
-        return _entries.getList();
-    }
-
-    public DatabaseEntry getEntryByUUID(UUID uuid) {
-        return _entries.getByUUID(uuid);
+    public UUIDMap<DatabaseEntry> getEntries() {
+        return _entries;
     }
 }

app/src/main/java/com/beemdevelopment/aegis/db/DatabaseEntry.java

@@ -5,17 +5,16 @@ import com.beemdevelopment.aegis.encoding.Base64Exception;
 import com.beemdevelopment.aegis.otp.GoogleAuthInfo;
 import com.beemdevelopment.aegis.otp.OtpInfo;
 import com.beemdevelopment.aegis.otp.OtpInfoException;
+import com.beemdevelopment.aegis.util.UUIDMap;
 
 import org.json.JSONException;
 import org.json.JSONObject;
 
-import java.io.Serializable;
 import java.util.Arrays;
 import java.util.Objects;
 import java.util.UUID;
 
-public class DatabaseEntry implements Serializable {
-    private UUID _uuid;
+public class DatabaseEntry extends UUIDMap.Value {
     private String _name = "";
     private String _issuer = "";
     private String _group;
@@ -23,12 +22,13 @@ public class DatabaseEntry implements Serializable {
     private byte[] _icon;
 
     private DatabaseEntry(UUID uuid, OtpInfo info) {
-        _uuid = uuid;
+        super(uuid);
         _info = info;
     }
 
     public DatabaseEntry(OtpInfo info) {
-        this(UUID.randomUUID(), info);
+        super();
+        _info = info;
     }
 
     public DatabaseEntry(OtpInfo info, String name, String issuer) {
@@ -46,7 +46,7 @@ public class DatabaseEntry implements Serializable {
 
         try {
             obj.put("type", _info.getType());
-            obj.put("uuid", _uuid.toString());
+            obj.put("uuid", getUUID().toString());
             obj.put("name", _name);
             obj.put("issuer", _issuer);
             obj.put("group", _group);
@@ -82,14 +82,6 @@ public class DatabaseEntry implements Serializable {
         return entry;
     }
 
-    public void resetUUID() {
-        _uuid = UUID.randomUUID();
-    }
-
-    public UUID getUUID() {
-        return _uuid;
-    }
-
     public String getName() {
         return _name;
     }
@@ -136,15 +128,12 @@ public class DatabaseEntry implements Serializable {
 
     @Override
     public boolean equals(Object o) {
-        if (this == o) {
-            return true;
-        }
         if (!(o instanceof DatabaseEntry)) {
             return false;
         }
 
         DatabaseEntry entry = (DatabaseEntry) o;
-        return getUUID().equals(entry.getUUID())
+        return super.equals(entry)
                 && getName().equals(entry.getName())
                 && getIssuer().equals(entry.getIssuer())
                 && Objects.equals(getGroup(), entry.getGroup())

app/src/main/java/com/beemdevelopment/aegis/db/DatabaseEntryList.java

@@ -1,62 +0,0 @@
-package com.beemdevelopment.aegis.db;
-
-import java.io.Serializable;
-import java.util.ArrayList;
-import java.util.Collections;
-import java.util.Iterator;
-import java.util.List;
-import java.util.UUID;
-
-import androidx.annotation.NonNull;
-
-public class DatabaseEntryList implements Iterable<DatabaseEntry>, Serializable {
-    private List<DatabaseEntry> _entries = new ArrayList<>();
-
-    @NonNull
-    @Override
-    public Iterator<DatabaseEntry> iterator() {
-        return _entries.iterator();
-    }
-
-    public void add(DatabaseEntry entry) {
-        if (getByUUID(entry.getUUID()) != null) {
-            throw new AssertionError("entry found with the same uuid");
-        }
-        _entries.add(entry);
-    }
-
-    public void remove(DatabaseEntry entry) {
-        entry = mustGetByUUID(entry.getUUID());
-        _entries.remove(entry);
-    }
-
-    public void replace(DatabaseEntry newEntry) {
-        DatabaseEntry oldEntry = mustGetByUUID(newEntry.getUUID());
-        _entries.set(_entries.indexOf(oldEntry), newEntry);
-    }
-
-    public void swap(DatabaseEntry entry1, DatabaseEntry entry2) {
-        Collections.swap(_entries, _entries.indexOf(entry1), _entries.indexOf(entry2));
-    }
-
-    public List<DatabaseEntry> getList() {
-        return Collections.unmodifiableList(_entries);
-    }
-
-    public DatabaseEntry getByUUID(UUID uuid) {
-        for (DatabaseEntry entry : _entries) {
-            if (entry.getUUID().equals(uuid)) {
-                return entry;
-            }
-        }
-        return null;
-    }
-
-    private DatabaseEntry mustGetByUUID(UUID uuid) {
-        DatabaseEntry entry = getByUUID(uuid);
-        if (entry == null) {
-            throw new AssertionError("no entry found with the same uuid");
-        }
-        return entry;
-    }
-}

app/src/main/java/com/beemdevelopment/aegis/db/DatabaseManager.java

@@ -16,7 +16,7 @@ import java.io.FileInputStream;
 import java.io.FileOutputStream;
 import java.io.IOException;
 import java.text.Collator;
-import java.util.List;
+import java.util.Collection;
 import java.util.TreeSet;
 import java.util.UUID;
 
@@ -136,32 +136,32 @@ public class DatabaseManager {
 
     public void addEntry(DatabaseEntry entry) {
         assertState(false, true);
-        _db.addEntry(entry);
+        _db.getEntries().add(entry);
     }
 
-    public void removeEntry(DatabaseEntry entry) {
+    public DatabaseEntry removeEntry(DatabaseEntry entry) {
         assertState(false, true);
-        _db.removeEntry(entry);
+        return _db.getEntries().remove(entry);
     }
 
-    public void replaceEntry(DatabaseEntry entry) {
+    public DatabaseEntry replaceEntry(DatabaseEntry entry) {
         assertState(false, true);
-        _db.replaceEntry(entry);
+        return _db.getEntries().replace(entry);
     }
 
     public void swapEntries(DatabaseEntry entry1, DatabaseEntry entry2) {
         assertState(false, true);
-        _db.swapEntries(entry1, entry2);
+        _db.getEntries().swap(entry1, entry2);
     }
 
-    public List<DatabaseEntry> getEntries() {
+    public boolean isEntryDuplicate(DatabaseEntry entry) {
         assertState(false, true);
-        return _db.getEntries();
+        return _db.getEntries().has(entry);
     }
 
-    public DatabaseEntry getEntryByUUID(UUID uuid) {
+    public Collection<DatabaseEntry> getEntries() {
         assertState(false, true);
-        return _db.getEntryByUUID(uuid);
+        return _db.getEntries().getValues();
     }
 
     public TreeSet<String> getGroups() {

app/src/main/java/com/beemdevelopment/aegis/db/slots/Slot.java

@@ -7,12 +7,12 @@ import com.beemdevelopment.aegis.crypto.MasterKey;
 import com.beemdevelopment.aegis.crypto.SCryptParameters;
 import com.beemdevelopment.aegis.encoding.Hex;
 import com.beemdevelopment.aegis.encoding.HexException;
+import com.beemdevelopment.aegis.util.UUIDMap;
 
 import org.json.JSONException;
 import org.json.JSONObject;
 
 import java.io.IOException;
-import java.io.Serializable;
 import java.security.InvalidAlgorithmParameterException;
 import java.security.InvalidKeyException;
 import java.security.NoSuchAlgorithmException;
@@ -25,26 +25,29 @@ import javax.crypto.NoSuchPaddingException;
 import javax.crypto.SecretKey;
 import javax.crypto.spec.SecretKeySpec;
 
-public abstract class Slot implements Serializable {
+public abstract class Slot extends UUIDMap.Value {
     public final static byte TYPE_RAW = 0x00;
     public final static byte TYPE_DERIVED = 0x01;
     public final static byte TYPE_FINGERPRINT = 0x02;
 
-    private UUID _uuid;
     private byte[] _encryptedMasterKey;
     private CryptParameters _encryptedMasterKeyParams;
 
     protected Slot() {
-        _uuid = UUID.randomUUID();
+        super();
     }
 
     protected Slot(UUID uuid, byte[] key, CryptParameters keyParams) {
-        _uuid = uuid;
+        super(uuid);
         _encryptedMasterKey = key;
         _encryptedMasterKeyParams = keyParams;
     }
 
-    // getKey decrypts the encrypted master key in this slot using the given cipher and returns it.
+    /**
+     * Decrypts the encrypted master key in this slot using the given cipher and returns it.
+     * @throws SlotException if a generic crypto operation error occurred.
+     * @throws SlotIntegrityException if an error occurred while verifying the integrity of the slot.
+     */
     public MasterKey getKey(Cipher cipher) throws SlotException, SlotIntegrityException {
         try {
             CryptResult res = CryptoUtils.decrypt(_encryptedMasterKey, cipher, _encryptedMasterKeyParams);
@@ -57,7 +60,10 @@ public abstract class Slot implements Serializable {
         }
     }
 
-    // setKey encrypts the given master key using the given cipher and stores the result in this slot.
+    /**
+     * Encrypts the given master key using the given cipher and stores the result in this slot.
+     * @throws SlotException if a generic crypto operation error occurred.
+     */
     public void setKey(MasterKey masterKey, Cipher cipher) throws SlotException {
         try {
             byte[] masterKeyBytes = masterKey.getBytes();
@@ -95,7 +101,7 @@ public abstract class Slot implements Serializable {
         try {
             JSONObject obj = new JSONObject();
             obj.put("type", getType());
-            obj.put("uuid", _uuid.toString());
+            obj.put("uuid", getUUID().toString());
             obj.put("key", Hex.encode(_encryptedMasterKey));
             obj.put("key_params", _encryptedMasterKeyParams.toJson());
             return obj;
@@ -146,8 +152,4 @@ public abstract class Slot implements Serializable {
     }
 
     public abstract byte getType();
-
-    public UUID getUUID() {
-        return _uuid;
-    }
 }

app/src/main/java/com/beemdevelopment/aegis/db/slots/SlotList.java

@@ -1,18 +1,15 @@
 package com.beemdevelopment.aegis.db.slots;
 
+import com.beemdevelopment.aegis.util.UUIDMap;
+
 import org.json.JSONArray;
 import org.json.JSONException;
 import org.json.JSONObject;
 
-import java.io.Serializable;
 import java.util.ArrayList;
-import java.util.Iterator;
 import java.util.List;
-import java.util.UUID;
-
-public class SlotList implements Iterable<Slot>, Serializable {
-    private List<Slot> _slots = new ArrayList<>();
 
+public class SlotList extends UUIDMap<Slot> {
     public JSONArray toJson() {
         JSONArray array = new JSONArray();
         for (Slot slot : this) {
@@ -38,23 +35,6 @@ public class SlotList implements Iterable<Slot>, Serializable {
         return slots;
     }
 
-    public void add(Slot slot) {
-        for (Slot s : this) {
-            if (s.getUUID().equals(slot.getUUID())) {
-                throw new AssertionError("slot found with the same uuid");
-            }
-        }
-        _slots.add(slot);
-    }
-
-    public void remove(Slot slot) {
-        _slots.remove(slot);
-    }
-
-    public int size() {
-        return _slots.size();
-    }
-
     public <T extends Slot> T find(Class<T> type) {
         for (Slot slot : this) {
             if (slot.getClass() == type) {
@@ -77,31 +57,4 @@ public class SlotList implements Iterable<Slot>, Serializable {
     public <T extends Slot> boolean has(Class<T> type) {
         return find(type) != null;
     }
-
-    public void replace(Slot newSlot) {
-        Slot oldSlot = mustGetByUUID(newSlot.getUUID());
-        _slots.set(_slots.indexOf(oldSlot), newSlot);
-    }
-
-    public Slot getByUUID(UUID uuid) {
-        for (Slot slot : _slots) {
-            if (slot.getUUID().equals(uuid)) {
-                return slot;
-            }
-        }
-        return null;
-    }
-
-    private Slot mustGetByUUID(UUID uuid) {
-        Slot slot = getByUUID(uuid);
-        if (slot == null) {
-            throw new AssertionError(String.format("no slot found with UUID: %s", uuid.toString()));
-        }
-        return slot;
-    }
-
-    @Override
-    public Iterator<Slot> iterator() {
-        return _slots.iterator();
-    }
 }

app/src/main/java/com/beemdevelopment/aegis/importers/DatabaseImporter.java

@@ -6,6 +6,7 @@ import android.net.Uri;
 
 import com.beemdevelopment.aegis.db.DatabaseEntry;
 import com.beemdevelopment.aegis.util.ByteInputStream;
+import com.beemdevelopment.aegis.util.UUIDMap;
 import com.topjohnwu.superuser.io.SuFile;
 import com.topjohnwu.superuser.io.SuFileInputStream;
 
@@ -115,7 +116,7 @@ public abstract class DatabaseImporter {
     }
 
     public static class Result {
-        private List<DatabaseEntry> _entries = new ArrayList<>();
+        private UUIDMap<DatabaseEntry> _entries = new UUIDMap<>();
         private List<DatabaseImporterEntryException> _errors = new ArrayList<>();
 
         public void addEntry(DatabaseEntry entry) {
@@ -126,7 +127,7 @@ public abstract class DatabaseImporter {
             _errors.add(error);
         }
 
-        public List<DatabaseEntry> getEntries() {
+        public UUIDMap<DatabaseEntry> getEntries() {
             return _entries;
         }
 

app/src/main/java/com/beemdevelopment/aegis/ui/EditEntryActivity.java

@@ -40,12 +40,9 @@ import com.bumptech.glide.Glide;
 import com.bumptech.glide.load.engine.DiskCacheStrategy;
 import com.bumptech.glide.request.target.CustomTarget;
 import com.bumptech.glide.request.transition.Transition;
+import com.beemdevelopment.aegis.util.Cloner;
 
-import java.io.ByteArrayInputStream;
 import java.io.ByteArrayOutputStream;
-import java.io.IOException;
-import java.io.ObjectInputStream;
-import java.io.ObjectOutputStream;
 import java.text.Collator;
 import java.util.ArrayList;
 import java.util.List;
@@ -391,6 +388,7 @@ public class EditEntryActivity extends AegisActivity {
         setResult(RESULT_OK, intent);
         finish();
     }
+
     @Override
     protected void onActivityResult(int requestCode, final int resultCode, Intent data) {
         if (requestCode == PICK_IMAGE_REQUEST && resultCode == RESULT_OK && data != null && data.getData() != null) {
@@ -492,7 +490,7 @@ public class EditEntryActivity extends AegisActivity {
         if (_origEntry == null) {
             entry = new DatabaseEntry(info);
         } else {
-            entry = cloneEntry(_origEntry);
+            entry = Cloner.clone(_origEntry);
             entry.setInfo(info);
         }
         entry.setIssuer(_textIssuer.getText().toString());
@@ -570,20 +568,6 @@ public class EditEntryActivity extends AegisActivity {
         return -1;
     }
 
-    private static DatabaseEntry cloneEntry(DatabaseEntry entry) {
-        try {
-            ByteArrayOutputStream baos = new ByteArrayOutputStream();
-            ObjectOutputStream oos = new ObjectOutputStream(baos);
-            oos.writeObject(entry);
-
-            ByteArrayInputStream bais = new ByteArrayInputStream(baos.toByteArray());
-            ObjectInputStream ois = new ObjectInputStream(bais);
-            return (DatabaseEntry) ois.readObject();
-        } catch (ClassNotFoundException | IOException e) {
-            throw new RuntimeException(e);
-        }
-    }
-
     private static class ParseException extends Exception {
         public ParseException(String message) {
             super(message);

app/src/main/java/com/beemdevelopment/aegis/ui/MainActivity.java

@@ -251,8 +251,8 @@ public class MainActivity extends AegisActivity implements EntryListView.Listene
             } else {
                 // this profile has been serialized/deserialized and is no longer the same instance it once was
                 // to deal with this, the replaceEntry functions are used
-                _db.replaceEntry(entry);
-                _entryListView.replaceEntry(entry);
+                DatabaseEntry oldEntry = _db.replaceEntry(entry);
+                _entryListView.replaceEntry(oldEntry, entry);
                 saveDatabase();
             }
         }
@@ -521,10 +521,10 @@ public class MainActivity extends AegisActivity implements EntryListView.Listene
     }
 
     private void deleteEntry(DatabaseEntry entry) {
-        _db.removeEntry(entry);
+        DatabaseEntry oldEntry = _db.removeEntry(entry);
         saveDatabase();
 
-        _entryListView.removeEntry(entry);
+        _entryListView.removeEntry(oldEntry);
     }
 
     @Override

app/src/main/java/com/beemdevelopment/aegis/ui/PreferencesFragment.java

@@ -38,6 +38,7 @@ import com.beemdevelopment.aegis.importers.DatabaseImporterException;
 import com.beemdevelopment.aegis.services.NotificationService;
 import com.beemdevelopment.aegis.ui.models.ImportEntry;
 import com.beemdevelopment.aegis.ui.preferences.SwitchPreference;
+import com.beemdevelopment.aegis.util.UUIDMap;
 import com.takisoft.preferencex.PreferenceFragmentCompat;
 import com.topjohnwu.superuser.Shell;
 import com.topjohnwu.superuser.io.SuFile;
@@ -76,7 +77,7 @@ public class PreferencesFragment extends PreferenceFragmentCompat {
     // keep a reference to the type of database converter the user selected
     private Class<? extends DatabaseImporter> _importerType;
     private AegisImporter.State _importerState;
-    private List<DatabaseEntry> _importerEntries;
+    private UUIDMap<DatabaseEntry> _importerEntries;
 
     private SwitchPreference _encryptionPreference;
     private SwitchPreference _fingerprintPreference;
@@ -620,20 +621,10 @@ public class PreferencesFragment extends PreferenceFragmentCompat {
 
         List<ImportEntry> selectedEntries = (ArrayList<ImportEntry>) data.getSerializableExtra("entries");
         for (ImportEntry selectedEntry : selectedEntries) {
-            DatabaseEntry savedEntry = null;
-            for (DatabaseEntry entry : _importerEntries) {
-                if (entry.getUUID().equals(selectedEntry.getUUID())) {
-                    savedEntry = entry;
-                    break;
-                }
-            }
-
-            if (savedEntry == null) {
-                throw new RuntimeException();
-            }
+            DatabaseEntry savedEntry = _importerEntries.getByUUID(selectedEntry.getUUID());
 
             // temporary: randomize the UUID of duplicate entries and add them anyway
-            if (_db.getEntryByUUID(savedEntry.getUUID()) != null) {
+            if (_db.isEntryDuplicate(savedEntry)) {
                 savedEntry.resetUUID();
             }
 

app/src/main/java/com/beemdevelopment/aegis/ui/views/EntryAdapter.java

@@ -17,7 +17,6 @@ import java.util.ArrayList;
 import java.util.Collections;
 import java.util.Comparator;
 import java.util.List;
-import java.util.UUID;
 
 import androidx.recyclerview.widget.RecyclerView;
 
@@ -109,7 +108,6 @@ public class EntryAdapter extends RecyclerView.Adapter<EntryHolder> implements I
     }
 
     public void removeEntry(DatabaseEntry entry) {
-        entry = getEntryByUUID(entry.getUUID());
         _entries.remove(entry);
 
         if (_shownEntries.contains(entry)) {
@@ -128,8 +126,7 @@ public class EntryAdapter extends RecyclerView.Adapter<EntryHolder> implements I
         checkPeriodUniformity();
     }
 
-    public void replaceEntry(DatabaseEntry newEntry) {
-        DatabaseEntry oldEntry = getEntryByUUID(newEntry.getUUID());
+    public void replaceEntry(DatabaseEntry oldEntry, DatabaseEntry newEntry) {
         _entries.set(_entries.indexOf(oldEntry), newEntry);
 
         if (_shownEntries.contains(oldEntry)) {
@@ -163,15 +160,6 @@ public class EntryAdapter extends RecyclerView.Adapter<EntryHolder> implements I
         return _searchFilter != null && !issuer.contains(_searchFilter);
     }
 
-    private DatabaseEntry getEntryByUUID(UUID uuid) {
-        for (DatabaseEntry entry : _entries) {
-            if (entry.getUUID().equals(uuid)) {
-                return entry;
-            }
-        }
-        throw new AssertionError("no entry found with the same id");
-    }
-
     public void refresh(boolean hard) {
         if (hard) {
             notifyDataSetChanged();

app/src/main/java/com/beemdevelopment/aegis/ui/views/EntryListView.java

@@ -225,8 +225,8 @@ public class EntryListView extends Fragment implements EntryAdapter.Listener {
         _adapter.clearEntries();
     }
 
-    public void replaceEntry(DatabaseEntry entry) {
-        _adapter.replaceEntry(entry);
+    public void replaceEntry(DatabaseEntry oldEntry, DatabaseEntry newEntry) {
+        _adapter.replaceEntry(oldEntry, newEntry);
     }
 
     public void runEntriesAnimation() {

app/src/main/java/com/beemdevelopment/aegis/util/Cloner.java

@@ -0,0 +1,32 @@
+package com.beemdevelopment.aegis.util;
+
+import java.io.ByteArrayInputStream;
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
+import java.io.ObjectInputStream;
+import java.io.ObjectOutputStream;
+import java.io.Serializable;
+
+public class Cloner {
+    private Cloner() {
+
+    }
+
+    /**
+     * Returns an exact clone of the given Serializable object.
+     */
+    @SuppressWarnings("unchecked cast")
+    public static <T extends Serializable> T clone(T obj) {
+        try {
+            ByteArrayOutputStream baos = new ByteArrayOutputStream();
+            ObjectOutputStream oos = new ObjectOutputStream(baos);
+            oos.writeObject(obj);
+
+            ByteArrayInputStream bais = new ByteArrayInputStream(baos.toByteArray());
+            ObjectInputStream ois = new ObjectInputStream(bais);
+            return (T) ois.readObject();
+        } catch (ClassNotFoundException | IOException e) {
+            throw new RuntimeException(e);
+        }
+    }
+}

app/src/main/java/com/beemdevelopment/aegis/util/UUIDMap.java

@@ -0,0 +1,162 @@
+package com.beemdevelopment.aegis.util;
+
+import androidx.annotation.NonNull;
+
+import java.io.Serializable;
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.Collections;
+import java.util.Iterator;
+import java.util.LinkedHashMap;
+import java.util.List;
+import java.util.UUID;
+
+/**
+ * A map data structure abstraction for storing values with a UUID as the key. Keys
+ * must be specified by the value itself, instead of separately. It uses a
+ * LinkedHashMap internally (a hash map with a separate linked list that maintains
+ * the order).
+ * @param <T> The type of values in this map
+ */
+public class UUIDMap <T extends UUIDMap.Value> implements Iterable<T>, Serializable {
+    private LinkedHashMap<UUID, T> _map = new LinkedHashMap<>();
+
+    /**
+     * Adds a value to the internal map.
+     * @throws AssertionError if a map value with the UUID of the given value already exists.
+     */
+    public void add(T value) {
+        UUID uuid = value.getUUID();
+        if (_map.containsKey(uuid)) {
+            throw new AssertionError(String.format("Existing value found with UUID: %s", uuid));
+        }
+        _map.put(uuid, value);
+    }
+
+    /**
+     * Removes a value from the internal map.
+     * @throws AssertionError if no map value exists with the UUID of the given value.
+     * @return The old value that is now no longer present in the internal map.
+     */
+    public T remove(T value) {
+        T oldValue = getByUUID(value.getUUID());
+        _map.remove(oldValue.getUUID());
+        return oldValue;
+    }
+
+    /**
+     * Replaces an old value (with the same UUID as the new given value) in the
+     * internal map with the new given value.
+     * @throws AssertionError if no map value exists with the UUID of the given value.
+     * @return The old value that is now no longer present in the internal map.
+     */
+    public T replace(T newValue) {
+        T oldValue = getByUUID(newValue.getUUID());
+        _map.put(oldValue.getUUID(), newValue);
+        return oldValue;
+    }
+
+    /**
+     * Swaps the position of value1 and value2 in the internal map. This operation is
+     * quite expensive because it has to reallocate the entire underlying LinkedHashMap.
+     * @throws AssertionError if no map value exists with the UUID of the given entries.
+     */
+    public void swap(T value1, T value2) {
+        boolean found1 = false;
+        boolean found2 = false;
+        List<T> values = new ArrayList<>();
+
+        for (T value : _map.values()) {
+            if (value.getUUID().equals(value1.getUUID())) {
+                values.add(value2);
+                found1 = true;
+            } else if (value.getUUID().equals(value2.getUUID())) {
+                values.add(value1);
+                found2 = true;
+            } else {
+                values.add(value);
+            }
+        }
+
+        if (!found1) {
+            throw new AssertionError(String.format("No value found for value1 with UUID: %s", value1.getUUID()));
+        }
+        if (!found2) {
+            throw new AssertionError(String.format("No value found for value2 with UUID: %s", value2.getUUID()));
+        }
+
+        _map.clear();
+        for (T value : values) {
+            _map.put(value.getUUID(), value);
+        }
+    }
+
+    /**
+     * Reports whether the internal map contains a value with the UUID of the given value.
+     */
+    public boolean has(T value) {
+        return _map.containsKey(value.getUUID());
+    }
+
+    /**
+     * Returns a read-only view of the values in the internal map.
+     */
+    public Collection<T> getValues() {
+        return Collections.unmodifiableCollection(_map.values());
+    }
+
+    /**
+     * Retrieves an entry from the internal map that has the given UUID.
+     * @throws AssertionError if no map value exists with the given UUID.
+     */
+    public T getByUUID(UUID uuid) {
+        T value = _map.get(uuid);
+        if (value == null) {
+            throw new AssertionError(String.format("No value found with UUID: %s", uuid));
+        }
+        return value;
+    }
+
+    @NonNull
+    @Override
+    public Iterator<T> iterator() {
+        return _map.values().iterator();
+    }
+
+    public static abstract class Value implements Serializable {
+        private UUID _uuid;
+
+        protected Value(UUID uuid) {
+            _uuid = uuid;
+        }
+
+        protected Value() {
+            this(UUID.randomUUID());
+        }
+
+        public final UUID getUUID() {
+            return _uuid;
+        }
+
+        /**
+         * Resets the UUID of this value by generating a new random one.
+         * The caller must ensure that this Value is not in a UUIDMap yet. Otherwise, bad things will happen.
+         */
+        public final void resetUUID() {
+            _uuid = UUID.randomUUID();
+        }
+
+        @Override
+        public boolean equals(Object o) {
+            if (this == o) {
+                return true;
+            }
+
+            if (!(o instanceof Value)) {
+                return false;
+            }
+
+            return getUUID().equals(((Value) o).getUUID());
+        }
+    }
+}

app/src/test/java/com/beemdevelopment/aegis/HOTPTest.java

@@ -3,12 +3,12 @@ package com.beemdevelopment.aegis;
 import com.beemdevelopment.aegis.crypto.otp.HOTP;
 import com.beemdevelopment.aegis.crypto.otp.OTP;
 
-import org.junit.Test;
+import org.junit.jupiter.api.Test;
 
 import java.security.InvalidKeyException;
 import java.security.NoSuchAlgorithmException;
 
-import static org.junit.Assert.*;
+import static org.junit.jupiter.api.Assertions.*;
 
 public class HOTPTest {
     // https://tools.ietf.org/html/rfc4226#page-32

app/src/test/java/com/beemdevelopment/aegis/SCryptTest.java

@@ -5,13 +5,13 @@ import com.beemdevelopment.aegis.crypto.SCryptParameters;
 import com.beemdevelopment.aegis.encoding.Hex;
 import com.beemdevelopment.aegis.encoding.HexException;
 
-import org.junit.Test;
+import org.junit.jupiter.api.Test;
 
 import java.util.Arrays;
 
 import javax.crypto.SecretKey;
 
-import static org.junit.Assert.*;
+import static org.junit.jupiter.api.Assertions.*;
 
 public class SCryptTest {
     @Test

app/src/test/java/com/beemdevelopment/aegis/TOTPTest.java

@@ -4,12 +4,12 @@ import com.beemdevelopment.aegis.crypto.otp.OTP;
 import com.beemdevelopment.aegis.crypto.otp.TOTP;
 import com.beemdevelopment.aegis.encoding.HexException;
 
-import org.junit.Test;
+import org.junit.jupiter.api.Test;
 
 import java.security.InvalidKeyException;
 import java.security.NoSuchAlgorithmException;
 
-import static org.junit.Assert.*;
+import static org.junit.jupiter.api.Assertions.*;
 
 public class TOTPTest {
     private static class Vector {

app/src/test/java/com/beemdevelopment/aegis/UUIDMapTest.java

@@ -0,0 +1,104 @@
+package com.beemdevelopment.aegis;
+
+import com.beemdevelopment.aegis.util.Cloner;
+import com.beemdevelopment.aegis.util.UUIDMap;
+
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.BeforeEach;
+
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.Collections;
+import java.util.List;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+public class UUIDMapTest {
+    private UUIDMap<Value> _map;
+
+    @BeforeEach
+    public void init() {
+        _map = new UUIDMap<>();
+    }
+
+    @Test
+    public void addValue() {
+        // try adding a new value
+        Value value = addNewValue();
+
+        // try re-adding the value
+        assertThrows(AssertionError.class, () -> _map.add(value));
+
+        // try adding a clone of the value
+        assertThrows(AssertionError.class, () -> _map.add(Cloner.clone(value)));
+    }
+
+    @Test
+    public void removeValue() {
+        // try removing a value
+        final Value value = addNewValue();
+        Value oldValue = _map.remove(value);
+        assertFalse(_map.has(value));
+
+        // ensure we got the original value back
+        assertEquals(value, oldValue);
+
+        // try removing a non-existent value
+        assertThrows(AssertionError.class, () -> _map.remove(value));
+
+        // try removing a value using a clone
+        Value value2 = addNewValue();
+        _map.remove(Cloner.clone(value2));
+        assertFalse(_map.has(value2));
+    }
+
+    @Test
+    public void replaceValue() {
+        Value value = addNewValue();
+
+        // replace the value with a clone
+        Value valueClone = Cloner.clone(value);
+        Value oldValue = _map.replace(valueClone);
+
+        // ensure we got the original value back
+        assertEquals(value, oldValue);
+
+        // ensure that the clone is now stored in the map
+        assertSame(_map.getByUUID(value.getUUID()), valueClone);
+    }
+
+    @Test
+    public void swapValue() {
+        Collection<Value> values = _map.getValues();
+
+        // set up the map with some values
+        Value value1 = addNewValue();
+        Value value2 = addNewValue();
+        Value value3 = addNewValue();
+        Value value4 = addNewValue();
+
+        // set up a reference list with the reverse order
+        List<Value> ref = new ArrayList<>(values);
+        Collections.reverse(ref);
+
+        // the lists should not be equal at this point
+        assertNotEquals(values, ref);
+
+        // swap the values and see if the lists are equal now
+        _map.swap(value1, value4);
+        _map.swap(value2, value3);
+        assertIterableEquals(values, ref);
+    }
+
+    private Value addNewValue() {
+        Value value = new Value();
+        assertFalse(_map.has(value));
+        _map.add(value);
+        assertTrue(_map.has(value));
+        return value;
+    }
+
+    private static class Value extends UUIDMap.Value {
+
+    }
+}

build.gradle

@@ -6,7 +6,7 @@ buildscript {
         google()
     }
     dependencies {
-        classpath 'com.android.tools.build:gradle:3.3.2'
+        classpath 'com.android.tools.build:gradle:3.4.1'
 
         // NOTE: Do not place your application dependencies here; they belong
         // in the individual module build.gradle files

gradle/wrapper/gradle-wrapper.properties

@@ -1,6 +1,6 @@
-#Tue Feb 26 19:31:04 CET 2019
+#Mon Jun 10 14:39:47 CEST 2019
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-4.10.1-all.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-5.1.1-all.zip