SnappyDB

SnappyDB is a key-value database for Android it's an alternative for SQLite if you want to use a NoSQL approach.

It allows you to store and get primitive types, but also a Serializable object or array in a type-safe way.

SnappyDB can outperform SQLite in read/write operations.

SnappyDB is based on leveldb and use snappy compression algorithm, on redundant content you could achieve a good compression ratio

Check out the Demo App

Usage

try {
   DB snappydb = DBFactory.open(context); //create or open an existing databse using the default name
   
   snappydb.put("name", "Jack Reacher"); 
   snappydb.putInt("age", 42);  
   snappydb.putBoolean("single", true);
   snappydb.put("books", new String[]{"One Shot", "Tripwire", "61 Hours"}); 
   
   String 	 name   =  snappydb.get("name");
   int 	 age    =  snappydb.getInt("age");
   boolean  single =  snappydb.getBoolean("single");
   String[] books  =  snappydb.getArray("books", String.class);// get array of string
   	
   snappydb.close();
   
   } catch (SnappydbException e) {
   }

For more recipes please take a look at the Cookbook.

With SnappyDB you could seamlessly store and retrieve your object/array, it uses Kryo serialization which is faster than the regular Java serialization.

Installation

SnappyDB uses native code for performance, it's available as an Android Library Project AAR.

dependencies {
    compile 'com.snappydb:snappydb-lib:0.4.0'
    compile 'com.esotericsoftware.kryo:kryo:2.24.0'
}

Cookbook

Common tasks snippets

Open/Create database
Close database
Destroy database
Insert primitive types
Read primitive types
Insert Serializable
Insert Object
Read Serializable
Read Object
Insert Array
Read Array
Check key
Delete key
Keys Search

Create database

Create using the default name

 DB snappydb = DBFactory.open(context);

Create with a given name

 DB snappydb = DBFactory.open(context, "books");

SnappyDB use the internal storage to create your database. It creates a directory containing all the necessary files Ex: /data/data/com.snappydb/files/mydatabse

Using the builder pattern

 DB snappyDB = new SnappyDB.Builder(context)
                    .directory(Environment.getExternalStorageDirectory().getAbsolutePath()) //optional
                    .name("books")//optional
                    .build();

directory Specify the location of the database (sdcard in this example)

Close database

snappydb.close();

Destroy database

snappydb.destroy();

Insert primitive types

snappyDB.put("quote", "bazinga!");

snappyDB.putShort("myshort", (short)32768);

snappyDB.putInt("max_int", Integer.MAX_VALUE);

snappyDB.putLong("max_long", Long.MAX_VALUE);

snappyDB.putDouble("max_double", Double.MAX_VALUE);

snappyDB.putFloat("myfloat", 10.30f);

snappyDB.putBoolean("myboolean", true);

Read primitive types

String quote      = snappyDB.get("quote");

short myshort     = snappyDB.getShort("myshort");

int maxInt        = snappyDB.getInt("max_int");

long maxLong      = snappyDB.getLong("max_long");

double maxDouble  = snappyDB.getDouble("max_double");

float myFloat     = snappyDB.getFloat("myfloat");

boolean myBoolean = snappyDB.getBoolean("myboolean");

Insert Serializable

AtomicInteger objAtomicInt = new AtomicInteger (42);
snappyDB.put("atomic integer", objAtomicInt);

Insert Object

MyPojo pojo = new MyPojo ();
snappyDB.put("my_pojo", pojo);

Note: MyPojo doesn't have to implement Serializable interface

Read Serializable

 AtomicInteger myObject = snappyDB.get("atomic integer", AtomicInteger.class);

Read Object

MyPojo myObject = snappyDB.getObject("non_serializable", MyPojo.class);

Note: MyPojo doesn't have to implement Serializable interface

Insert Array

Number[] array = {new AtomicInteger (42), new BigDecimal("10E8"), Double.valueOf(Math.PI)};

snappyDB.put("array", array);

Read Array

Number [] numbers = snappyDB.getObjectArray("array", Number.class);

Check Key

boolean isKeyExist = snappyDB.exists("key");

Delete Key

snappyDB.del("key");

Keys Search

By Prefix

snappyDB.put("android:03", "Cupcake"); // adding 0 to maintain lexicographical order
snappyDB.put("android:04", "Donut");
snappyDB.put("android:05", "Eclair");
snappyDB.put("android:08", "Froyo");
snappyDB.put("android:09", "Gingerbread");
snappyDB.put("android:11", "Honeycomb");
snappyDB.put("android:14", "Ice Cream Sandwich");
snappyDB.put("android:16", "Jelly Bean");
snappyDB.put("android:19", "KitKat");

String [] keys = snappyDB.findKeys("android");
assert keys.length == 9;

keys = snappyDB.findKeys("android:0");
assert keys.length == 5;

assert snappyDB.get(keys[0]).equals("Cupcake");
assert snappyDB.get(keys[1]).equals("Donut");
assert snappyDB.get(keys[2]).equals("Eclair");
assert snappyDB.get(keys[3]).equals("Froyo");
assert snappyDB.get(keys[4]).equals("Gingerbread");

keys = snappyDB.findKeys("android:1");
assert keys.length == 4;

assert snappyDB.get(keys[0]).equals("Honeycomb");
assert snappyDB.get(keys[1]).equals("Ice Cream Sandwich");
assert snappyDB.get(keys[2]).equals("Jelly Bean");
assert snappyDB.get(keys[3]).equals("KitKat");

By Range [from .. to]

both 'FROM' & 'TO' keys exist

keys = snappyDB.findKeysBetween("android:08", "android:11");
assertEquals(3, keys.length);
assertEquals("android:08", keys[0]);
assertEquals("android:09", keys[1]);
assertEquals("android:11", keys[2]);

'FROM' key exist, but not the `TO

keys = snappyDB.findKeysBetween("android:05", "android:10");
assertEquals(3, keys.length);
assertEquals("android:05", keys[0]);
assertEquals("android:08", keys[1]);
assertEquals("android:09", keys[2]);

'FROM' key doesn't exist but the 'TO' key do

keys = snappyDB.findKeysBetween("android:07", "android:09");
assertEquals(2, keys.length);
assertEquals("android:08", keys[0]);
assertEquals("android:09", keys[1]);

both 'FROM' & 'TO' keys doesn't exist

keys = snappyDB.findKeysBetween("android:13", "android:99");
assertEquals(3, keys.length);
assertEquals("android:14", keys[0]);
assertEquals("android:16", keys[1]);
assertEquals("android:19", keys[2]);

License

SnappyDB is opensource, contribution and feedback are welcomed

Copyright 2013 Nabil HACHICHA.

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.

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