Sharding Pattern (#1056)

* Create sharding module

* Add Unit Tests

* Fix readme hyperlink

* Fix check-style issue

sharding/src/test/java/com/iluwatar/sharding/AppTest.java

@@ -0,0 +1,39 @@
+/*
+ * The MIT License
+ * Copyright © 2014-2019 Ilkka Seppälä
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+package com.iluwatar.sharding;
+
+import org.junit.Test;
+
+/**
+ * Unit tests for App class.
+ */
+public class AppTest {
+
+  @Test
+  public void testMain() {
+    String[] args = {};
+    App.main(args);
+  }
+
+}

sharding/src/test/java/com/iluwatar/sharding/HashShardManagerTest.java

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+/*
+ * The MIT License
+ * Copyright © 2014-2019 Ilkka Seppälä
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+package com.iluwatar.sharding;
+
+import org.junit.After;
+import org.junit.Assert;
+import org.junit.Before;
+import org.junit.Test;
+
+/**
+ * Unit tests for HashShardManager class.
+ */
+public class HashShardManagerTest {
+
+  private HashShardManager hashShardManager;
+
+  /**
+   * Initialize hashShardManager instance.
+   */
+  @Before
+  public void setup() {
+    hashShardManager = new HashShardManager();
+    var shard1 = new Shard(1);
+    var shard2 = new Shard(2);
+    var shard3 = new Shard(3);
+    hashShardManager.addNewShard(shard1);
+    hashShardManager.addNewShard(shard2);
+    hashShardManager.addNewShard(shard3);
+  }
+
+  @After
+  public void tearDown() {
+
+  }
+
+  @Test
+  public void testStoreData() {
+    var data = new Data(1, "test", Data.DataType.type1);
+    hashShardManager.storeData(data);
+    Assert.assertEquals(data, hashShardManager.getShardById(1).getDataById(1));
+  }
+
+}

sharding/src/test/java/com/iluwatar/sharding/LookupShardManagerTest.java

@@ -0,0 +1,68 @@
+/*
+ * The MIT License
+ * Copyright © 2014-2019 Ilkka Seppälä
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+package com.iluwatar.sharding;
+
+import java.util.Map;
+
+import org.junit.Assert;
+import org.junit.Before;
+import org.junit.Test;
+
+/**
+ * Unit tests for LookupShardManager class.
+ */
+public class LookupShardManagerTest {
+
+  private LookupShardManager lookupShardManager;
+
+  /**
+   * Initialize lookupShardManager instance.
+   */
+  @Before
+  public void setup() {
+    lookupShardManager = new LookupShardManager();
+    var shard1 = new Shard(1);
+    var shard2 = new Shard(2);
+    var shard3 = new Shard(3);
+    lookupShardManager.addNewShard(shard1);
+    lookupShardManager.addNewShard(shard2);
+    lookupShardManager.addNewShard(shard3);
+  }
+
+  @Test
+  public void testStoreData() {
+    try {
+      var data = new Data(1, "test", Data.DataType.type1);
+      lookupShardManager.storeData(data);
+      var field = LookupShardManager.class.getDeclaredField("lookupMap");
+      field.setAccessible(true);
+      Map<Integer, Integer> lookupMap = (Map<Integer, Integer>) field.get(lookupShardManager);
+      var shardId = lookupMap.get(1);
+      var shard = lookupShardManager.getShardById(shardId);
+      Assert.assertEquals(data, shard.getDataById(1));
+    } catch (NoSuchFieldException | IllegalAccessException e) {
+      Assert.fail("Fail to modify field access.");
+    }
+  }
+}

sharding/src/test/java/com/iluwatar/sharding/RangeShardManagerTest.java

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+/*
+ * The MIT License
+ * Copyright © 2014-2019 Ilkka Seppälä
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+package com.iluwatar.sharding;
+
+import org.junit.Assert;
+import org.junit.Before;
+import org.junit.Test;
+
+/**
+ * Unit tests for RangeShardManager class.
+ */
+public class RangeShardManagerTest {
+
+  private RangeShardManager rangeShardManager;
+
+  /**
+   * Initialize rangeShardManager instance.
+   */
+  @Before
+  public void setup() {
+    rangeShardManager = new RangeShardManager();
+    var shard1 = new Shard(1);
+    var shard2 = new Shard(2);
+    var shard3 = new Shard(3);
+    rangeShardManager.addNewShard(shard1);
+    rangeShardManager.addNewShard(shard2);
+    rangeShardManager.addNewShard(shard3);
+  }
+
+  @Test
+  public void testStoreData() {
+    var data = new Data(1, "test", Data.DataType.type1);
+    rangeShardManager.storeData(data);
+    Assert.assertEquals(data, rangeShardManager.getShardById(1).getDataById(1));
+  }
+
+}

sharding/src/test/java/com/iluwatar/sharding/ShardManagerTest.java

@@ -0,0 +1,104 @@
+/*
+ * The MIT License
+ * Copyright © 2014-2019 Ilkka Seppälä
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+package com.iluwatar.sharding;
+
+import java.util.Map;
+
+import org.junit.After;
+import org.junit.Assert;
+import org.junit.Before;
+import org.junit.Test;
+
+/**
+ * Unit tests for ShardManager class.
+ */
+public class ShardManagerTest {
+
+  private ShardManager shardManager;
+
+  /**
+   * Initialize shardManager instance.
+   */
+  @Before
+  public void setup() {
+    shardManager = new TestShardManager();
+  }
+
+  @After
+  public void tearDown() {
+
+  }
+
+  @Test
+  public void testAddNewShard() {
+    try {
+      var shard = new Shard(1);
+      shardManager.addNewShard(shard);
+      var field = ShardManager.class.getDeclaredField("shardMap");
+      field.setAccessible(true);
+      Map<Integer, Shard> map = (Map<Integer, Shard>) field.get(shardManager);
+      Assert.assertEquals(1, map.size());
+      Assert.assertEquals(shard, map.get(1));
+    } catch (NoSuchFieldException | IllegalAccessException e) {
+      Assert.fail("Fail to modify field access.");
+    }
+  }
+
+  @Test
+  public void testRemoveShardById() {
+    try {
+      var shard = new Shard(1);
+      shardManager.addNewShard(shard);
+      boolean flag = shardManager.removeShardById(1);
+      var field = ShardManager.class.getDeclaredField("shardMap");
+      field.setAccessible(true);
+      Map<Integer, Shard> map = (Map<Integer, Shard>) field.get(shardManager);
+      Assert.assertEquals(true, flag);
+      Assert.assertEquals(0, map.size());
+    } catch (IllegalAccessException | NoSuchFieldException e) {
+      Assert.fail("Fail to modify field access.");
+    }
+  }
+
+  @Test
+  public void testGetShardById() {
+    Shard shard = new Shard(1);
+    shardManager.addNewShard(shard);
+    Shard tmpShard = shardManager.getShardById(1);
+    Assert.assertEquals(shard, tmpShard);
+  }
+
+  class TestShardManager extends ShardManager {
+
+    @Override
+    public int storeData(Data data) {
+      return 0;
+    }
+
+    @Override
+    protected int allocateShard(Data data) {
+      return 0;
+    }
+  }
+}

sharding/src/test/java/com/iluwatar/sharding/ShardTest.java

@@ -0,0 +1,83 @@
+/*
+ * The MIT License
+ * Copyright © 2014-2019 Ilkka Seppälä
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+package com.iluwatar.sharding;
+
+import java.util.HashMap;
+import java.util.Map;
+
+import org.junit.After;
+import org.junit.Assert;
+import org.junit.Before;
+import org.junit.Test;
+
+
+/**
+ * Unit tests for Shard class.
+ */
+public class ShardTest {
+
+  private Data data;
+
+  private Shard shard;
+
+  @Before
+  public void setup() {
+    data = new Data(1, "test", Data.DataType.type1);
+    shard = new Shard(1);
+  }
+
+  @After
+  public void tearDown() {}
+
+  @Test
+  public void testStoreData() {
+    try {
+      shard.storeData(data);
+      var field = Shard.class.getDeclaredField("dataStore");
+      field.setAccessible(true);
+      Map<Integer, Data> dataMap = (Map<Integer, Data>) field.get(shard);
+      Assert.assertEquals(1, dataMap.size());
+      Assert.assertEquals(data, dataMap.get(1));
+    } catch (NoSuchFieldException | IllegalAccessException e) {
+      Assert.fail("Fail to modify field access.");
+    }
+
+  }
+
+  @Test
+  public void testClearData() {
+    try {
+      Map<Integer, Data> dataMap = new HashMap<>();
+      dataMap.put(1, data);
+      var field = Shard.class.getDeclaredField("dataStore");
+      field.setAccessible(true);
+      field.set(shard, dataMap);
+      shard.clearData();
+      dataMap = (Map<Integer, Data>) field.get(shard);
+      Assert.assertEquals(0, dataMap.size());
+    } catch (NoSuchFieldException | IllegalAccessException e) {
+      Assert.fail("Fail to modify field access.");
+    }
+  }
+}