Duty/cycle v2

app/src/main/java/eu/faircode/email/DutyCycle.java

@@ -0,0 +1,73 @@
+package eu.faircode.email;
+
+/*
+    This file is part of FairEmail.
+
+    FairEmail is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    FairEmail is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with FairEmail.  If not, see <http://www.gnu.org/licenses/>.
+
+    Copyright 2018-2022 by Marcel Bokhorst (M66B)
+*/
+
+import java.util.Date;
+
+public class DutyCycle {
+    private final String name;
+    private final long interval;
+    private final long duration;
+
+    private Long last = null;
+    private long start;
+    private long idle = 0;
+    private long busy = 0;
+
+    private static final long YIELD_INTERVAL = 15 * 1000L; // milliseconds
+    private static final long YIELD_DURATION = 1500L; // milliseconds
+
+    public DutyCycle(String name) {
+        this(name, YIELD_INTERVAL, YIELD_DURATION);
+    }
+
+    public DutyCycle(String name, long interval, long duration) {
+        this.name = name;
+        this.interval = interval;
+        this.duration = duration;
+    }
+
+    public void start() {
+        start = new Date().getTime();
+    }
+
+    public void stop() {
+        long end = new Date().getTime();
+
+        if (last != null)
+            idle += (start - last);
+        last = end;
+
+        busy += (end - start);
+
+        if (busy + idle > interval) {
+            long wait = (duration - idle);
+            Log.i(name + " busy=" + busy + " idle=" + idle + " wait=" + wait);
+            if (wait > 0)
+                try {
+                    Thread.sleep(wait);
+                } catch (InterruptedException ex) {
+                    Log.w(ex);
+                }
+            idle = 0;
+            busy = 0;
+        }
+    }
+}