RFR 9: 8064932: test java/lang/ProcessBuilder/Basic.java: waitFor didn't take long enough

[Martin Buchholz]

Hi David,

I'm still hoping to persuade you (and others) to fix the long-standing
return-early bug in Object.wait.

As new support for my position I offer the "at least" in  JLS
https://docs.oracle.com/javase/specs/jls/se8/html/jls-17.html#jls-17.2.1

"""

If this is a timed wait, an internal action removing t from m's wait
set that occurs after at least millisecs milliseconds plusnanosecs
nanoseconds elapse since the beginning of this wait action.

"""

--- a/src/java.base/share/classes/java/lang/Object.java
+++ b/src/java.base/share/classes/java/lang/Object.java
@@ -444,16 +444,17 @@
      *             this exception is thrown.
      */
     public final void wait(long timeout, int nanos) throws
InterruptedException {
-        if (timeout < 0) {
-            throw new IllegalArgumentException("timeout value is negative");
-        }
+        if (nanos != 0) {
+            if (timeout < 0) {
+                throw new IllegalArgumentException
+                    ("timeout value is negative");
+            }

-        if (nanos < 0 || nanos > 999999) {
-            throw new IllegalArgumentException(
-                                "nanosecond timeout value out of range");
-        }
+            if (nanos < 0 || nanos > 999999) {
+                throw new IllegalArgumentException
+                    ("nanosecond timeout value out of range");
+            }

-        if (nanos >= 500000 || (nanos != 0 && timeout == 0)) {
             timeout++;
         }



On Mon, Nov 17, 2014 at 6:11 PM, David Holmes <david.holmes at oracle.com> wrote:

>> On 11/17/2014 2:54 PM, Martin Buchholz wrote:
>>>
>>> Returning early is EVIL.
>
>
> Yet every OS seems to allow it <sigh>