Java tutorial
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See the License for the * specific language governing permissions and limitations * under the License. * */ package org.apache.cassandra.db.context; import static org.junit.Assert.*; import java.net.InetAddress; import java.net.UnknownHostException; import java.nio.ByteBuffer; import java.util.*; import org.apache.commons.lang.ArrayUtils; import org.junit.Test; import org.apache.cassandra.Util; import org.apache.cassandra.db.context.IContext.ContextRelationship; import static org.apache.cassandra.db.context.CounterContext.ContextState; import org.apache.cassandra.utils.ByteBufferUtil; import org.apache.cassandra.utils.NodeId; public class CounterContextTest { private static final CounterContext cc = new CounterContext(); private static final int idLength; private static final int clockLength; private static final int countLength; private static final int stepLength; static { idLength = NodeId.LENGTH; // size of int clockLength = 8; // size of long countLength = 8; // size of long stepLength = idLength + clockLength + countLength; } @Test public void testCreate() { ByteBuffer context = cc.create(4); assert context.remaining() == stepLength + 4; } @Test public void testDiff() { ContextState left = ContextState.allocate(3, 0); ContextState right; // equality: equal nodes, all counts same left.writeElement(NodeId.fromInt(3), 3L, 0L); left.writeElement(NodeId.fromInt(6), 2L, 0L); left.writeElement(NodeId.fromInt(9), 1L, 0L); right = new ContextState(ByteBufferUtil.clone(left.context), left.headerLength); assert ContextRelationship.EQUAL == cc.diff(left.context, right.context); // greater than: left has superset of nodes (counts equal) left = ContextState.allocate(4, 0); left.writeElement(NodeId.fromInt(3), 3L, 0L); left.writeElement(NodeId.fromInt(6), 2L, 0L); left.writeElement(NodeId.fromInt(9), 1L, 0L); left.writeElement(NodeId.fromInt(12), 0L, 0L); right = ContextState.allocate(3, 0); right.writeElement(NodeId.fromInt(3), 3L, 0L); right.writeElement(NodeId.fromInt(6), 2L, 0L); right.writeElement(NodeId.fromInt(9), 1L, 0L); assert ContextRelationship.GREATER_THAN == cc.diff(left.context, right.context); // less than: left has subset of nodes (counts equal) left = ContextState.allocate(3, 0); left.writeElement(NodeId.fromInt(3), 3L, 0L); left.writeElement(NodeId.fromInt(6), 2L, 0L); left.writeElement(NodeId.fromInt(9), 1L, 0L); right = ContextState.allocate(4, 0); right.writeElement(NodeId.fromInt(3), 3L, 0L); right.writeElement(NodeId.fromInt(6), 2L, 0L); right.writeElement(NodeId.fromInt(9), 1L, 0L); right.writeElement(NodeId.fromInt(12), 0L, 0L); assert ContextRelationship.LESS_THAN == cc.diff(left.context, right.context); // greater than: equal nodes, but left has higher counts left = ContextState.allocate(3, 0); left.writeElement(NodeId.fromInt(3), 3L, 0L); left.writeElement(NodeId.fromInt(6), 2L, 0L); left.writeElement(NodeId.fromInt(9), 3L, 0L); right = ContextState.allocate(3, 0); right.writeElement(NodeId.fromInt(3), 3L, 0L); right.writeElement(NodeId.fromInt(6), 2L, 0L); right.writeElement(NodeId.fromInt(9), 1L, 0L); assert ContextRelationship.GREATER_THAN == cc.diff(left.context, right.context); // less than: equal nodes, but right has higher counts left = ContextState.allocate(3, 0); left.writeElement(NodeId.fromInt(3), 3L, 0L); left.writeElement(NodeId.fromInt(6), 2L, 0L); left.writeElement(NodeId.fromInt(9), 3L, 0L); right = ContextState.allocate(3, 0); right.writeElement(NodeId.fromInt(3), 3L, 0L); right.writeElement(NodeId.fromInt(6), 9L, 0L); right.writeElement(NodeId.fromInt(9), 3L, 0L); assert ContextRelationship.LESS_THAN == cc.diff(left.context, right.context); // disjoint: right and left have disjoint node sets left = ContextState.allocate(3, 0); left.writeElement(NodeId.fromInt(3), 1L, 0L); left.writeElement(NodeId.fromInt(4), 1L, 0L); left.writeElement(NodeId.fromInt(9), 1L, 0L); right = ContextState.allocate(3, 0); right.writeElement(NodeId.fromInt(3), 1L, 0L); right.writeElement(NodeId.fromInt(6), 1L, 0L); right.writeElement(NodeId.fromInt(9), 1L, 0L); assert ContextRelationship.DISJOINT == cc.diff(left.context, right.context); left = ContextState.allocate(3, 0); left.writeElement(NodeId.fromInt(3), 1L, 0L); left.writeElement(NodeId.fromInt(4), 1L, 0L); left.writeElement(NodeId.fromInt(9), 1L, 0L); right = ContextState.allocate(3, 0); right.writeElement(NodeId.fromInt(2), 1L, 0L); right.writeElement(NodeId.fromInt(6), 1L, 0L); right.writeElement(NodeId.fromInt(12), 1L, 0L); assert ContextRelationship.DISJOINT == cc.diff(left.context, right.context); // disjoint: equal nodes, but right and left have higher counts in differing nodes left = ContextState.allocate(3, 0); left.writeElement(NodeId.fromInt(3), 1L, 0L); left.writeElement(NodeId.fromInt(6), 3L, 0L); left.writeElement(NodeId.fromInt(9), 1L, 0L); right = ContextState.allocate(3, 0); right.writeElement(NodeId.fromInt(3), 1L, 0L); right.writeElement(NodeId.fromInt(6), 1L, 0L); right.writeElement(NodeId.fromInt(9), 5L, 0L); assert ContextRelationship.DISJOINT == cc.diff(left.context, right.context); left = ContextState.allocate(3, 0); left.writeElement(NodeId.fromInt(3), 2L, 0L); left.writeElement(NodeId.fromInt(6), 3L, 0L); left.writeElement(NodeId.fromInt(9), 1L, 0L); right = ContextState.allocate(3, 0); right.writeElement(NodeId.fromInt(3), 1L, 0L); right.writeElement(NodeId.fromInt(6), 9L, 0L); right.writeElement(NodeId.fromInt(9), 5L, 0L); assert ContextRelationship.DISJOINT == cc.diff(left.context, right.context); // disjoint: left has more nodes, but lower counts left = ContextState.allocate(4, 0); left.writeElement(NodeId.fromInt(3), 2L, 0L); left.writeElement(NodeId.fromInt(6), 3L, 0L); left.writeElement(NodeId.fromInt(9), 1L, 0L); left.writeElement(NodeId.fromInt(12), 1L, 0L); right = ContextState.allocate(3, 0); right.writeElement(NodeId.fromInt(3), 4L, 0L); right.writeElement(NodeId.fromInt(6), 9L, 0L); right.writeElement(NodeId.fromInt(9), 5L, 0L); assert ContextRelationship.DISJOINT == cc.diff(left.context, right.context); // disjoint: left has less nodes, but higher counts left = ContextState.allocate(3, 0); left.writeElement(NodeId.fromInt(3), 5L, 0L); left.writeElement(NodeId.fromInt(6), 3L, 0L); left.writeElement(NodeId.fromInt(9), 2L, 0L); right = ContextState.allocate(4, 0); right.writeElement(NodeId.fromInt(3), 4L, 0L); right.writeElement(NodeId.fromInt(6), 3L, 0L); right.writeElement(NodeId.fromInt(9), 2L, 0L); right.writeElement(NodeId.fromInt(12), 1L, 0L); assert ContextRelationship.DISJOINT == cc.diff(left.context, right.context); // disjoint: mixed nodes and counts left = ContextState.allocate(3, 0); left.writeElement(NodeId.fromInt(3), 5L, 0L); left.writeElement(NodeId.fromInt(6), 2L, 0L); left.writeElement(NodeId.fromInt(9), 2L, 0L); right = ContextState.allocate(4, 0); right.writeElement(NodeId.fromInt(3), 4L, 0L); right.writeElement(NodeId.fromInt(6), 3L, 0L); right.writeElement(NodeId.fromInt(9), 2L, 0L); right.writeElement(NodeId.fromInt(12), 1L, 0L); assert ContextRelationship.DISJOINT == cc.diff(left.context, right.context); left = ContextState.allocate(4, 0); left.writeElement(NodeId.fromInt(3), 5L, 0L); left.writeElement(NodeId.fromInt(6), 2L, 0L); left.writeElement(NodeId.fromInt(7), 2L, 0L); left.writeElement(NodeId.fromInt(9), 2L, 0L); right = ContextState.allocate(3, 0); right.writeElement(NodeId.fromInt(3), 4L, 0L); right.writeElement(NodeId.fromInt(6), 3L, 0L); right.writeElement(NodeId.fromInt(9), 2L, 0L); assert ContextRelationship.DISJOINT == cc.diff(left.context, right.context); } @Test public void testMerge() { // note: local counts aggregated; remote counts are reconciled (i.e. take max) ContextState left = ContextState.allocate(4, 1); left.writeElement(NodeId.fromInt(1), 1L, 1L); left.writeElement(NodeId.fromInt(2), 2L, 2L); left.writeElement(NodeId.fromInt(4), 6L, 3L); left.writeElement(NodeId.getLocalId(), 7L, 3L, true); ContextState right = ContextState.allocate(3, 1); right.writeElement(NodeId.fromInt(4), 4L, 4L); right.writeElement(NodeId.fromInt(5), 5L, 5L); right.writeElement(NodeId.getLocalId(), 2L, 9L, true); ByteBuffer merged = cc.merge(left.context, right.context); int hd = 4; assertEquals(hd + 5 * stepLength, merged.remaining()); // local node id's counts are aggregated assert Util.equalsNodeId(NodeId.getLocalId(), merged, hd + 4 * stepLength); assertEquals(9L, merged.getLong(hd + 4 * stepLength + idLength)); assertEquals(12L, merged.getLong(hd + 4 * stepLength + idLength + clockLength)); // remote node id counts are reconciled (i.e. take max) assert Util.equalsNodeId(NodeId.fromInt(4), merged, hd + 2 * stepLength); assertEquals(6L, merged.getLong(hd + 2 * stepLength + idLength)); assertEquals(3L, merged.getLong(hd + 2 * stepLength + idLength + clockLength)); assert Util.equalsNodeId(NodeId.fromInt(5), merged, hd + 3 * stepLength); assertEquals(5L, merged.getLong(hd + 3 * stepLength + idLength)); assertEquals(5L, merged.getLong(hd + 3 * stepLength + idLength + clockLength)); assert Util.equalsNodeId(NodeId.fromInt(2), merged, hd + 1 * stepLength); assertEquals(2L, merged.getLong(hd + 1 * stepLength + idLength)); assertEquals(2L, merged.getLong(hd + 1 * stepLength + idLength + clockLength)); assert Util.equalsNodeId(NodeId.fromInt(1), merged, hd + 0 * stepLength); assertEquals(1L, merged.getLong(hd + 0 * stepLength + idLength)); assertEquals(1L, merged.getLong(hd + 0 * stepLength + idLength + clockLength)); } @Test public void testTotal() { ContextState left = ContextState.allocate(4, 1); left.writeElement(NodeId.fromInt(1), 1L, 1L); left.writeElement(NodeId.fromInt(2), 2L, 2L); left.writeElement(NodeId.fromInt(4), 3L, 3L); left.writeElement(NodeId.getLocalId(), 3L, 3L, true); ContextState right = ContextState.allocate(3, 1); right.writeElement(NodeId.fromInt(4), 4L, 4L); right.writeElement(NodeId.fromInt(5), 5L, 5L); right.writeElement(NodeId.getLocalId(), 9L, 9L, true); ByteBuffer merged = cc.merge(left.context, right.context); // 127.0.0.1: 12 (3+9) // 0.0.0.1: 1 // 0.0.0.2: 2 // 0.0.0.4: 4 // 0.0.0.5: 5 assertEquals(24L, cc.total(merged)); } @Test public void testMergeOldShards() { long now = System.currentTimeMillis(); NodeId id1 = NodeId.fromInt(1); NodeId id3 = NodeId.fromInt(3); List<NodeId.NodeIdRecord> records = new ArrayList<NodeId.NodeIdRecord>(); records.add(new NodeId.NodeIdRecord(id1, 2L)); records.add(new NodeId.NodeIdRecord(id3, 4L)); // Destination of merge is a delta ContextState ctx = ContextState.allocate(5, 2); ctx.writeElement(id1, 1L, 1L); ctx.writeElement(NodeId.fromInt(2), 2L, 2L); ctx.writeElement(id3, 3L, 3L, true); ctx.writeElement(NodeId.fromInt(4), 6L, 3L); ctx.writeElement(NodeId.fromInt(5), 7L, 3L, true); ByteBuffer merger = cc.computeOldShardMerger(ctx.context, records); ContextState m = new ContextState(merger); assert m.getNodeId().equals(id1); assert m.getClock() <= -now; assert m.getCount() == 0; m.moveToNext(); assert m.getNodeId().equals(id3); assert m.getClock() == 4L; assert m.getCount() == 1L; assert cc.total(ctx.context) == cc.total(cc.merge(ctx.context, merger)); // Source of merge is a delta ctx = ContextState.allocate(4, 1); ctx.writeElement(id1, 1L, 1L, true); ctx.writeElement(NodeId.fromInt(2), 2L, 2L); ctx.writeElement(id3, 3L, 3L); ctx.writeElement(NodeId.fromInt(4), 6L, 3L); merger = cc.computeOldShardMerger(ctx.context, records); assert cc.total(ctx.context) == cc.total(cc.merge(ctx.context, merger)); // source and destination of merge are deltas ctx = ContextState.allocate(4, 2); ctx.writeElement(id1, 1L, 1L, true); ctx.writeElement(NodeId.fromInt(2), 2L, 2L); ctx.writeElement(id3, 3L, 3L, true); ctx.writeElement(NodeId.fromInt(4), 6L, 3L); merger = cc.computeOldShardMerger(ctx.context, records); assert cc.total(ctx.context) == cc.total(cc.merge(ctx.context, merger)); // none of source and destination of merge are deltas ctx = ContextState.allocate(4, 0); ctx.writeElement(id1, 1L, 1L); ctx.writeElement(NodeId.fromInt(2), 2L, 2L); ctx.writeElement(id3, 3L, 3L); ctx.writeElement(NodeId.fromInt(4), 6L, 3L); merger = cc.computeOldShardMerger(ctx.context, records); assert cc.total(ctx.context) == cc.total(cc.merge(ctx.context, merger)); } @Test public void testRemoveOldShards() { NodeId id1 = NodeId.fromInt(1); NodeId id3 = NodeId.fromInt(3); NodeId id6 = NodeId.fromInt(6); List<NodeId.NodeIdRecord> records = new ArrayList<NodeId.NodeIdRecord>(); records.add(new NodeId.NodeIdRecord(id1, 2L)); records.add(new NodeId.NodeIdRecord(id3, 4L)); records.add(new NodeId.NodeIdRecord(id6, 10L)); ContextState ctx = ContextState.allocate(6, 2); ctx.writeElement(id1, 1L, 1L); ctx.writeElement(NodeId.fromInt(2), 2L, 2L); ctx.writeElement(id3, 3L, 3L, true); ctx.writeElement(NodeId.fromInt(4), 6L, 3L); ctx.writeElement(NodeId.fromInt(5), 7L, 3L, true); ctx.writeElement(id6, 5L, 6L); ByteBuffer merger = cc.computeOldShardMerger(ctx.context, records); ByteBuffer merged = cc.merge(ctx.context, merger); assert cc.total(ctx.context) == cc.total(merged); ByteBuffer cleaned = cc.removeOldShards(merged, (int) (System.currentTimeMillis() / 1000) + 1); assert cc.total(ctx.context) == cc.total(cleaned); assert cleaned.remaining() == ctx.context.remaining() - stepLength; merger = cc.computeOldShardMerger(cleaned, records); merged = cc.merge(cleaned, merger); assert cc.total(ctx.context) == cc.total(merged); cleaned = cc.removeOldShards(merged, (int) (System.currentTimeMillis() / 1000) + 1); assert cc.total(ctx.context) == cc.total(cleaned); assert cleaned.remaining() == ctx.context.remaining() - 2 * stepLength - 2; } }