TimeZoneUsage

WARNING

FragileCode

Summary

Derive the current time from an existing Clock Spring bean, and don’t rely on a Clock’s time zone

Suppression

Suppress false positives by adding the suppression annotation @SuppressWarnings("TimeZoneUsage") to the enclosing element.

Disable this pattern completely by adding -Xep:TimeZoneUsage:OFF as compiler argument. Learn more.

Samples

Identification

Shows code lines which will (not) be flagged by this bug pattern.
A //BUG: Diagnostic contains: comment is placed above any violating line.

import static java.time.ZoneOffset.UTC;

import java.time.Clock;
import java.time.Duration;
import java.time.Instant;
import java.time.LocalDate;
import java.time.LocalDateTime;
import java.time.LocalTime;
import java.time.OffsetDateTime;
import java.time.OffsetTime;
import java.time.ZoneId;
import java.time.ZonedDateTime;

class A {
  void m() {
    Clock clock = Clock.fixed(Instant.EPOCH, UTC);
    clock.instant();
    clock.millis();
    Clock.offset(clock, Duration.ZERO);
    Clock.tick(clock, Duration.ZERO);

    // BUG: Diagnostic contains:
    Clock.systemUTC();
    // BUG: Diagnostic contains:
    Clock.systemDefaultZone();
    // BUG: Diagnostic contains:
    Clock.system(UTC);
    // BUG: Diagnostic contains:
    Clock.tickMillis(UTC);
    // BUG: Diagnostic contains:
    Clock.tickMinutes(UTC);
    // BUG: Diagnostic contains:
    Clock.tickSeconds(UTC);
    // BUG: Diagnostic contains:
    clock.getZone();
    // BUG: Diagnostic contains:
    clock.withZone(UTC);

    // BUG: Diagnostic contains:
    Instant.now();
    // This is equivalent to `clock.instant()`, which is fine.
    Instant.now(clock);

    // BUG: Diagnostic contains:
    LocalDate.now();
    // BUG: Diagnostic contains:
    LocalDate.now(clock);
    // BUG: Diagnostic contains:
    LocalDate.now(UTC);

    // BUG: Diagnostic contains:
    LocalDateTime.now();
    // BUG: Diagnostic contains:
    LocalDateTime.now(clock);
    // BUG: Diagnostic contains:
    LocalDateTime.now(UTC);

    // BUG: Diagnostic contains:
    LocalTime.now();
    // BUG: Diagnostic contains:
    LocalTime.now(clock);
    // BUG: Diagnostic contains:
    LocalTime.now(UTC);

    // BUG: Diagnostic contains:
    OffsetDateTime.now();
    // BUG: Diagnostic contains:
    OffsetDateTime.now(clock);
    // BUG: Diagnostic contains:
    OffsetDateTime.now(UTC);

    // BUG: Diagnostic contains:
    OffsetTime.now();
    // BUG: Diagnostic contains:
    OffsetTime.now(clock);
    // BUG: Diagnostic contains:
    OffsetTime.now(UTC);

    // BUG: Diagnostic contains:
    ZonedDateTime.now();
    // BUG: Diagnostic contains:
    ZonedDateTime.now(clock);
    // BUG: Diagnostic contains:
    ZonedDateTime.now(UTC);
  }

  abstract class ForwardingClock extends Clock {
    private final Clock clock;

    ForwardingClock(Clock clock) {
      this.clock = clock;
    }

    @Override
    public ZoneId getZone() {
      return clock.getZone();
    }

    @Override
    public Clock withZone(ZoneId zone) {
      return clock.withZone(zone);
    }
  }
}