From d8a3bcbc38f10c866bcf795831eb75f2fd71bb08 Mon Sep 17 00:00:00 2001
From: James Hilliard <james.hilliard1@gmail.com>
Date: Thu, 27 May 2021 01:34:40 -0600
Subject: [PATCH] Use monotonic clocks for JESpace timeouts.

---
 .../src/main/java/org/jpos/space/JESpace.java | 37 ++++++++++---------
 .../java/org/jpos/space/JESpaceTestCase.java  |  5 +--
 2 files changed, 22 insertions(+), 20 deletions(-)

diff --git a/jpos/src/main/java/org/jpos/space/JESpace.java b/jpos/src/main/java/org/jpos/space/JESpace.java
index 529552edc0..d904aecc9a 100644
--- a/jpos/src/main/java/org/jpos/space/JESpace.java
+++ b/jpos/src/main/java/org/jpos/space/JESpace.java
@@ -44,7 +44,6 @@
 import org.jpos.iso.ISOUtil;
 import org.jpos.util.Log;
 import org.jpos.util.Loggeable;
-import org.jpos.util.Profiler;
 
 /**
  * BerkeleyDB Jave Edition based persistent space implementation
@@ -175,13 +174,14 @@ public synchronized V in (Object key) {
     @SuppressWarnings("unchecked")
     public synchronized V in (Object key, long timeout) {
         Object obj;
-        Instant now = Instant.now();
-        long duration;
+        Duration to = Duration.ofMillis(timeout);
+        Duration now = Duration.ofNanos(System.nanoTime());
+        Duration duration;
         while ((obj = inp (key)) == null &&
-                (duration = Duration.between(now, Instant.now()).toMillis()) < timeout)
+                to.compareTo(duration = Duration.ofNanos(System.nanoTime()).minus(now)) > 0)
         {
             try {
-                this.wait (timeout - duration);
+                this.wait (Math.max(to.minus(duration).toMillis(), 1L));
             } catch (InterruptedException ignored) { }
         }
         return (V) obj;
@@ -200,13 +200,14 @@ public synchronized V rd  (Object key) {
     @SuppressWarnings("unchecked")
     public synchronized V rd  (Object key, long timeout) {
         Object obj;
-        Instant now = Instant.now();
-        long duration;
+        Duration to = Duration.ofMillis(timeout);
+        Duration now = Duration.ofNanos(System.nanoTime());
+        Duration duration;
         while ((obj = rdp (key)) == null &&
-                (duration = Duration.between(now, Instant.now()).toMillis()) < timeout)
+                to.compareTo(duration = Duration.ofNanos(System.nanoTime()).minus(now)) > 0)
         {
             try {
-                this.wait (timeout - duration);
+                this.wait (Math.max(to.minus(duration).toMillis(), 1L));
             } catch (InterruptedException ignored) { }
         }
         return (V) obj;
@@ -220,13 +221,14 @@ public synchronized void nrd  (Object key) {
     }
     public synchronized V nrd  (Object key, long timeout) {
         Object obj;
-        Instant now = Instant.now();
-        long duration;
+        Duration to = Duration.ofMillis(timeout);
+        Duration now = Duration.ofNanos(System.nanoTime());
+        Duration duration;
         while ((obj = rdp (key)) != null &&
-                (duration = Duration.between(now, Instant.now()).toMillis()) < timeout)
+                to.compareTo(duration = Duration.ofNanos(System.nanoTime()).minus(now)) > 0)
         {
             try {
-                this.wait (Math.min(NRD_RESOLUTION, timeout - duration));
+                this.wait (Math.min(NRD_RESOLUTION, Math.max(to.minus(duration).toMillis(), 1L)));
             } catch (InterruptedException ignored) { }
         }
         return (V) obj;
@@ -249,14 +251,15 @@ public boolean existAny (Object[] keys) {
         return false;
     }
     public boolean existAny (Object[] keys, long timeout) {
-        Instant now = Instant.now();
-        long duration;
-        while ((duration = Duration.between(now, Instant.now()).toMillis()) < timeout) {
+        Duration to = Duration.ofMillis(timeout);
+        Duration now = Duration.ofNanos(System.nanoTime());
+        Duration duration;
+        while (to.compareTo(duration = Duration.ofNanos(System.nanoTime()).minus(now)) > 0) {
             if (existAny (keys))
                 return true;
             synchronized (this) {
                 try {
-                    wait (timeout - duration);
+                    wait (Math.max(to.minus(duration).toMillis(), 1L));
                 } catch (InterruptedException ignored) { }
             }
         }
diff --git a/jpos/src/test/java/org/jpos/space/JESpaceTestCase.java b/jpos/src/test/java/org/jpos/space/JESpaceTestCase.java
index 526715a8ff..1db59daf7d 100644
--- a/jpos/src/test/java/org/jpos/space/JESpaceTestCase.java
+++ b/jpos/src/test/java/org/jpos/space/JESpaceTestCase.java
@@ -38,7 +38,6 @@
 import java.io.IOException;
 import java.nio.file.Path;
 import java.time.Duration;
-import java.time.Instant;
 
 @SuppressWarnings("unchecked")
 public class JESpaceTestCase {
@@ -204,11 +203,11 @@ public void run() {
                 sp.out ("KA", Boolean.TRUE);
             }
         }.start();
-        Instant now = Instant.now();
+        Duration now = Duration.ofNanos(System.nanoTime());
         assertTrue(
             sp.existAny(new String[]{"KA", "KB"}, 2000L),
             "existAnyWithTimeout ([KA,KB], delay)");
-        long elapsed = Duration.between(now, Instant.now()).toMillis();
+        long elapsed = Duration.ofNanos(System.nanoTime()).minus(now).toMillis();
         assertTrue(elapsed > 900L, "delay was > 1000");
         assertNotNull(sp.inp("KA"), "Entry should not be null");
     }