console.sh

# compile
$ javac -cp cron4j-2.2.5.jar Cron4jTzTest.java

# expected result if default time zone is Europe/Rome
$ java -cp cron4j-2.2.5.jar:. -Duser.timezone=Europe/Rome Cron4jTzTest
next time = 2016-08-02T00:00:00Z

# unexpected behavior
$ java -cp cron4j-2.2.5.jar:. -Duser.timezone=America/Los_Angeles Cron4jTzTest
next time = 2016-08-01T07:00:00Z

cron4j-tz-fix.patch

diff -Nurp cron4j-2.2.5/src/it/sauronsoftware/cron4j/Predictor.java cron4j-2.2.5-tz-fix/src/it/sauronsoftware/cron4j/Predictor.java
--- cron4j-2.2.5/src/it/sauronsoftware/cron4j/Predictor.java	2011-12-28 19:03:04.000000000 -0800
+++ cron4j-2.2.5-tz-fix/src/it/sauronsoftware/cron4j/Predictor.java	2016-08-01 14:31:06.000000000 -0700
@@ -164,7 +164,7 @@ public class Predictor {
 		// Go a minute ahead.
 		time += 60000;
 		// Is it matching?
-		if (schedulingPattern.match(time)) {
+		if (schedulingPattern.match(timeZone, time)) {
 			return time;
 		}
 		// Go through the matcher groups.

Cron4jTzTest.java

import it.sauronsoftware.cron4j.Predictor;
import it.sauronsoftware.cron4j.SchedulingPattern;
import java.util.Date;
import java.util.TimeZone;
import java.time.Instant;

public class Cron4jTzTest {
    public static void main(String[] args) {
        final TimeZone scheduleTimeZone = TimeZone.getTimeZone("UTC");

        // daily pattern
        SchedulingPattern pattern = new SchedulingPattern("0 0 * * *") {
            // work-around:
            //@Override
            //public boolean match(long millis) {
            //    return match(scheduleTimeZone, millis);
            //}
        };

        // 2016-08-01 00:00:00 -0700 == 2016-08-01 07:00:00 UTC
        Instant instant = Instant.parse("2016-08-01T07:00:00Z").minusSeconds(1);

        Predictor utcPredicator = new Predictor(pattern, Date.from(instant));
        utcPredicator.setTimeZone(scheduleTimeZone);

        long nextTime = utcPredicator.nextMatchingTime();
        System.out.println("next time = " + Instant.ofEpochMilli(nextTime));
    }
}