Merge pull request #1911 from koo-taejin/#1883

added to insert a number of agent into rdb periodically. #1883

web/src/main/java/com/navercorp/pinpoint/web/dao/memory/MemoryAgentStatisticsDao.java

@@ -0,0 +1,65 @@
+package com.navercorp.pinpoint.web.dao.memory;
+
+import com.navercorp.pinpoint.web.dao.AgentStatisticsDao;
+import com.navercorp.pinpoint.web.vo.AgentCountStatistics;
+import com.navercorp.pinpoint.web.vo.Range;
+import org.springframework.stereotype.Repository;
+
+import java.util.ArrayList;
+import java.util.Comparator;
+import java.util.Iterator;
+import java.util.List;
+import java.util.Map;
+import java.util.TreeMap;
+
+/**
+ * @author Taejin Koo
+ */
+@Repository
+public class MemoryAgentStatisticsDao implements AgentStatisticsDao {
+
+    private Map<Long, Integer> agentCountPerTime = new TreeMap<>(new LongComparator());
+
+    @Override
+    public boolean insertAgentCount(AgentCountStatistics agentCountStatistics) {
+        agentCountPerTime.put(agentCountStatistics.getTimestamp(), agentCountStatistics.getAgentCount());
+        return true;
+    }
+
+    @Override
+    public List<AgentCountStatistics> selectAgentCount(Range range) {
+        Long to = range.getTo();
+        long from = range.getFrom();
+
+        List<AgentCountStatistics> result = new ArrayList<>();
+
+        Iterator<Map.Entry<Long, Integer>> iterator = agentCountPerTime.entrySet().iterator();
+        while (iterator.hasNext()) {
+            Map.Entry<Long, Integer> next = iterator.next();
+
+            Long key = next.getKey();
+            if (key > to) {
+                continue;
+            }
+            if (key < from) {
+                break;
+            }
+
+            result.add(new AgentCountStatistics(next.getValue(), key));
+        }
+
+        return result;
+    }
+
+    private static class LongComparator implements Comparator<Long> {
+
+        @Override
+        public int compare(Long o1, Long o2) {
+            int compare = Long.compare(o2, o1);
+
+            // if same then overwrite.
+            return compare;
+        }
+    }
+
+}

web/src/test/java/com/navercorp/pinpoint/web/dao/memory/MemoryAgentStatisticsDaoTest.java

@@ -0,0 +1,62 @@
+package com.navercorp.pinpoint.web.dao.memory;
+
+import com.navercorp.pinpoint.web.vo.AgentCountStatistics;
+import com.navercorp.pinpoint.web.vo.Range;
+import org.junit.Assert;
+import org.junit.BeforeClass;
+import org.junit.Test;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.concurrent.ThreadLocalRandom;
+
+/**
+ * @author Taejin Koo
+ */
+public class MemoryAgentStatisticsDaoTest {
+
+    private static List<AgentCountStatistics> testDataList;
+
+    @BeforeClass
+    public static void setup() {
+        testDataList = createTestData(100);
+    }
+
+    private static List<AgentCountStatistics> createTestData(int size) {
+        List<AgentCountStatistics> data = new ArrayList<>(size);
+
+        for (int i = 0; i < size; i++) {
+            AgentCountStatistics agentCountStatistics = new AgentCountStatistics(ThreadLocalRandom.current().nextInt(0, Integer.MAX_VALUE), (i * 100) + 100);
+            data.add(agentCountStatistics);
+        }
+
+        return data;
+    }
+
+    @Test
+    public void simpleTest() throws Exception {
+        MemoryAgentStatisticsDao dao = new MemoryAgentStatisticsDao();
+        for (AgentCountStatistics testData : testDataList) {
+            dao.insertAgentCount(testData);
+        }
+
+        Range range = new Range(660L, 1320L);
+        List<AgentCountStatistics> agentCountStatisticses = dao.selectAgentCount(range);
+        Assert.assertEquals(7, agentCountStatisticses.size());
+
+
+        range = new Range(7100L, System.currentTimeMillis());
+        agentCountStatisticses = dao.selectAgentCount(range);
+        Assert.assertEquals(30, agentCountStatisticses.size());
+
+        range = new Range(0L, System.currentTimeMillis());
+        agentCountStatisticses = dao.selectAgentCount(range);
+        Assert.assertEquals(100, agentCountStatisticses.size());
+
+        long currentTime = System.currentTimeMillis();
+        range = new Range(currentTime, currentTime + 100);
+        agentCountStatisticses = dao.selectAgentCount(range);
+        Assert.assertEquals(0, agentCountStatisticses.size());
+    }
+
+}