WindowedOperator initial value

[AlexP11223]

WindowedOperator initializes maxWindowTime to 0, so if we use real timestamps or something else starting not from 0 in time column, then we will get a lot of empty panes until it reaches these values.

Is it intended to work like that?

I think it can be easily fixed/improved by adding setter for this value allowing the client to initialize it to any needed value,

For example like this

--- a/lib/src/main/java/edu/stanford/futuredata/macrobase/operator/WindowedOperator.java
+++ b/lib/src/main/java/edu/stanford/futuredata/macrobase/operator/WindowedOperator.java
@@ -19,7 +19,7 @@ public class WindowedOperator<O>
     private double windowLength = 60.0;
     private double slideLength = 10.0;

-    private double maxWindowTime;
+    private double maxWindowTime = Double.MAX_VALUE;
     private IncrementalOperator<O> op;

     private ArrayList<DataFrame> batchBuffer;
@@ -28,7 +28,9 @@ public class WindowedOperator<O>
         this.op = op;
     }
     public WindowedOperator<O> initialize() {
-        this.maxWindowTime = 0.0;
+        if (maxWindowTime == Double.MAX_VALUE) {
+            this.maxWindowTime = 0.0;
+        }
         this.batchBuffer = new ArrayList<>();

         int numPanes = (int)Math.ceil(windowLength / slideLength);
@@ -134,6 +136,10 @@ public class WindowedOperator<O>
         return maxWindowTime;
     }

+    public void setMaxWindowTime(double maxWindowTime) {
+        this.maxWindowTime = maxWindowTime;
+    }
+
     public int getBufferSize() {
         return batchBuffer.size();
     }

By the way, what's the reason for adding initialize method instead of doing it in the constructor?

UPD: ah, I guess it's because windowSize has to be set via setter from the interface. But maxWindowTime probably can be initialized during construction.

--- a/lib/src/main/java/edu/stanford/futuredata/macrobase/operator/WindowedOperator.java
+++ b/lib/src/main/java/edu/stanford/futuredata/macrobase/operator/WindowedOperator.java
@@ -19,7 +19,7 @@ public class WindowedOperator<O>
     private double windowLength = 60.0;
     private double slideLength = 10.0;

-    private double maxWindowTime;
+    private double maxWindowTime = 0.0;
     private IncrementalOperator<O> op;

     private ArrayList<DataFrame> batchBuffer;
@@ -28,7 +28,6 @@ public class WindowedOperator<O>
         this.op = op;
     }
     public WindowedOperator<O> initialize() {
-        this.maxWindowTime = 0.0;
         this.batchBuffer = new ArrayList<>();

         int numPanes = (int)Math.ceil(windowLength / slideLength);
@@ -134,6 +133,10 @@ public class WindowedOperator<O>
         return maxWindowTime;
     }

+    public void setMaxWindowTime(double maxWindowTime) {
+        this.maxWindowTime = maxWindowTime;
+    }
+
     public int getBufferSize() {
         return batchBuffer.size();
     }