TimeZoneUsage

WARNING

FragileCode

View source code on GitHub

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

Replacement

Shows the difference in example code before and after the bug pattern is applied.

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;
import reactor.core.publisher.Mono;

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.getZone();
    // BUG: Diagnostic contains:
    Mono.fromSupplier(clock::getZone);
    // BUG: Diagnostic contains:
    clock.withZone(UTC);
    // BUG: Diagnostic contains:
    Mono.<ZoneId>empty().map(clock::withZone);
    // BUG: Diagnostic contains:
    Clock.system(UTC);
    // BUG: Diagnostic contains:
    Mono.<ZoneId>empty().map(Clock::system);
    // BUG: Diagnostic contains:
    Clock.systemDefaultZone();
    // BUG: Diagnostic contains:
    Mono.fromSupplier(Clock::systemDefaultZone);
    // BUG: Diagnostic contains:
    Clock.systemUTC();
    // BUG: Diagnostic contains:
    Mono.fromSupplier(Clock::systemUTC);
    // BUG: Diagnostic contains:
    Clock.tickMillis(UTC);
    // BUG: Diagnostic contains:
    Mono.<ZoneId>empty().map(Clock::tickMillis);
    // BUG: Diagnostic contains:
    Clock.tickMinutes(UTC);
    // BUG: Diagnostic contains:
    Mono.<ZoneId>empty().map(Clock::tickMinutes);
    // BUG: Diagnostic contains:
    Clock.tickSeconds(UTC);
    // BUG: Diagnostic contains:
    Mono.<ZoneId>empty().map(Clock::tickSeconds);

    Instant.now(clock);
    Mono.<Clock>empty().map(Instant::now);
    // BUG: Diagnostic contains:
    Instant.now();
    // BUG: Diagnostic contains:
    Mono.fromSupplier(Instant::now);

    // BUG: Diagnostic contains:
    LocalDate.now();
    // BUG: Diagnostic contains:
    Mono.fromSupplier(LocalDate::now);
    // BUG: Diagnostic contains:
    LocalDate.now(clock);
    // BUG: Diagnostic contains:
    Mono.<Clock>empty().map(LocalDate::now);
    // BUG: Diagnostic contains:
    LocalDate.now(UTC);
    // BUG: Diagnostic contains:
    Mono.<ZoneId>empty().map(LocalDate::now);

    // BUG: Diagnostic contains:
    LocalDateTime.now();
    // BUG: Diagnostic contains:
    Mono.fromSupplier(LocalDateTime::now);
    // BUG: Diagnostic contains:
    LocalDateTime.now(clock);
    // BUG: Diagnostic contains:
    Mono.<Clock>empty().map(LocalDateTime::now);
    // BUG: Diagnostic contains:
    LocalDateTime.now(UTC);
    // BUG: Diagnostic contains:
    Mono.<ZoneId>empty().map(LocalDateTime::now);

    // BUG: Diagnostic contains:
    LocalTime.now();
    // BUG: Diagnostic contains:
    Mono.fromSupplier(LocalTime::now);
    // BUG: Diagnostic contains:
    LocalTime.now(clock);
    // BUG: Diagnostic contains:
    Mono.<Clock>empty().map(LocalTime::now);
    // BUG: Diagnostic contains:
    LocalTime.now(UTC);
    // BUG: Diagnostic contains:
    Mono.<ZoneId>empty().map(LocalTime::now);

    // BUG: Diagnostic contains:
    OffsetDateTime.now();
    // BUG: Diagnostic contains:
    Mono.fromSupplier(OffsetDateTime::now);
    // BUG: Diagnostic contains:
    OffsetDateTime.now(clock);
    // BUG: Diagnostic contains:
    Mono.<Clock>empty().map(OffsetDateTime::now);
    // BUG: Diagnostic contains:
    OffsetDateTime.now(UTC);
    // BUG: Diagnostic contains:
    Mono.<ZoneId>empty().map(OffsetDateTime::now);

    // BUG: Diagnostic contains:
    OffsetTime.now();
    // BUG: Diagnostic contains:
    Mono.fromSupplier(OffsetTime::now);
    // BUG: Diagnostic contains:
    OffsetTime.now(clock);
    // BUG: Diagnostic contains:
    Mono.<Clock>empty().map(OffsetTime::now);
    // BUG: Diagnostic contains:
    OffsetTime.now(UTC);
    // BUG: Diagnostic contains:
    Mono.<ZoneId>empty().map(OffsetTime::now);

    // BUG: Diagnostic contains:
    ZonedDateTime.now();
    // BUG: Diagnostic contains:
    Mono.fromSupplier(ZonedDateTime::now);
    // BUG: Diagnostic contains:
    ZonedDateTime.now(clock);
    // BUG: Diagnostic contains:
    Mono.<Clock>empty().map(ZonedDateTime::now);
    // BUG: Diagnostic contains:
    ZonedDateTime.now(UTC);
    // BUG: Diagnostic contains:
    Mono.<ZoneId>empty().map(ZonedDateTime::now);
  }

  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);
    }
  }
}