Refac waiting time

Adjust/adjust/src/main/java/com/adjust/sdk/BackoffStrategy.java

@@ -7,43 +7,43 @@ public enum BackoffStrategy {
     LONG_WAIT(1,                        // min retries
             2 * Constants.ONE_MINUTE,   // milliseconds multiplier
             24 * Constants.ONE_HOUR,    // max wait time
-            50,                         // min jitter multiplier
-            100),                       // max jitter multiplier
+            0.5,                        // min jitter multiplier
+            1.0),                       // max jitter multiplier
 
-    // 0.1-0.2, 0.2-0.4, 0.4-0.8, ... 1m
+    // 0.1-0.2, 0.2-0.4, 0.4-0.8, ... 1h
     SHORT_WAIT(1,                   // min retries
             200,                    // milliseconds multiplier
             Constants.ONE_MINUTE,   // max wait time
-            50,                     // min jitter multiplier
-            100),                   // max jitter multiplier
+            0.5,                    // min jitter multiplier
+            1.0),                   // max jitter multiplier
 
     TEST_WAIT(1,                    // min retries
             200,                    // milliseconds multiplier
             1000,                   // max wait time
-            50,                     // min jitter multiplier
-            100),                   // max jitter multiplier
+            0.5,                    // min jitter multiplier
+            1.0),                   // max jitter multiplier
 
     NO_WAIT(100,                    // min retries
             1,                      // milliseconds multiplier
             Constants.ONE_SECOND,   // max wait time
-            1,                      // min jitter multiplier
-            1);                     // max jitter multiplier
+            1.0,                    // min jitter multiplier
+            1.0);                   // max jitter multiplier
 
-    int minRetries;
+    int minRetries; // retries before starting backoff
     long milliSecondMultiplier;
     long maxWait;
-    int minJitter;
-    int maxJitter;
+    double minRange;
+    double maxRange;
 
     BackoffStrategy(int minRetries,
                     long milliSecondMultiplier,
                     long maxWait,
-                    int minJitter,
-                    int maxJitter) {
+                    double minRange,
+                    double maxRange) {
         this.minRetries = minRetries;
         this.milliSecondMultiplier = milliSecondMultiplier;
         this.maxWait = maxWait;
-        this.minJitter = minJitter;
-        this.maxJitter = maxJitter;
+        this.minRange = minRange;
+        this.maxRange = maxRange;
     }
 }

Adjust/adjust/src/main/java/com/adjust/sdk/Util.java

@@ -527,19 +527,24 @@ public static long getWaitingTime(int retries, BackoffStrategy backoffStrategy)
         if (retries < backoffStrategy.minRetries) {
             return 0;
         }
-        // start with base 0
-        int base = retries - backoffStrategy.minRetries;
-        // get the exponential Time from the base: 1, 2, 4, 8, 16, ... * times the multiplier
-        long exponentialTime = (((long) Math.pow(2, base)) * backoffStrategy.milliSecondMultiplier);
+        // start with expon 0
+        int expon = retries - backoffStrategy.minRetries;
+        // get the exponential Time from the power of 2: 1, 2, 4, 8, 16, ... * times the multiplier
+        long exponentialTime = ((long) Math.pow(2, expon)) * backoffStrategy.milliSecondMultiplier;
         // limit the maximum allowed time to wait
         long ceilingTime = Math.min(exponentialTime, backoffStrategy.maxWait);
-        Random random = new Random();
-        // add 1 to allow maximum value
-        int jitterFactorBase = random.nextInt(backoffStrategy.maxJitter - backoffStrategy.minJitter + 1);
-        int jitterFactorAdjusted = jitterFactorBase + backoffStrategy.minJitter;
-        double jitterFactor = jitterFactorAdjusted / 100.0;
+        // get the random range
+        double randomDouble = randomInRange(backoffStrategy.minRange, backoffStrategy.maxRange);
         // apply jitter factor
-        double waitingTime =  ceilingTime * jitterFactor;
+        double waitingTime =  ceilingTime * randomDouble;
         return (long)waitingTime;
     }
+
+    private static double randomInRange(double minRange, double maxRange) {
+        Random random = new Random();
+        double range = maxRange - minRange;
+        double scaled = random.nextDouble() * range;
+        double shifted = scaled + minRange;
+        return shifted;
+    }
 }