declare namespace java {
    namespace time {
        namespace chrono {
            /**
             * An era of the time-line.
             * <p>
             * Most calendar systems have a single epoch dividing the time-line into two eras.
             * However, some calendar systems, have multiple eras, such as one for the reign
             * of each leader.
             * In all cases, the era is conceptually the largest division of the time-line.
             * Each chronology defines the Era's that are known Eras and a
             * {@link Chronology#eras Chronology.eras} to get the valid eras.
             * <p>
             * For example, the Thai Buddhist calendar system divides time into two eras,
             * before and after a single date. By contrast, the Japanese calendar system
             * has one era for the reign of each Emperor.
             * <p>
             * Instances of {@code Era} may be compared using the {@code ==} operator.
             * @implSpec This interface must be implemented with care to ensure other classes operate correctly.
             *  All implementations must be singletons - final, immutable and thread-safe.
             *  It is recommended to use an enum whenever possible.
             * @since 1.8
             */
            // @ts-ignore
            interface Era extends java.time.temporal.TemporalAccessor, java.time.temporal.TemporalAdjuster {
                /**
                 * Gets the numeric value associated with the era as defined by the chronology.
                 * Each chronology defines the predefined Eras and methods to list the Eras
                 * of the chronology.
                 * <p>
                 * All fields, including eras, have an associated numeric value.
                 * The meaning of the numeric value for era is determined by the chronology
                 * according to these principles:
                 * <ul>
                 * <li>The era in use at the epoch 1970-01-01 (ISO) has the value 1.
                 * <li>Later eras have sequentially higher values.
                 * <li>Earlier eras have sequentially lower values, which may be negative.
                 * </ul>
                 * @return the numeric era value
                 */
                // @ts-ignore
                getValue(): number /*int*/
                /**
                 * Checks if the specified field is supported.
                 * <p>
                 * This checks if this era can be queried for the specified field.
                 * If false, then calling the {@link #range(TemporalField) range} and
                 * {@link #get(TemporalField) get} methods will throw an exception.
                 * <p>
                 * If the field is a {@link ChronoField} then the query is implemented here.
                 * The {@code ERA} field returns true.
                 * All other {@code ChronoField} instances will return false.
                 * <p>
                 * If the field is not a {@code ChronoField}, then the result of this method
                 * is obtained by invoking {@code TemporalField.isSupportedBy(TemporalAccessor)}
                 * passing {@code this} as the argument.
                 * Whether the field is supported is determined by the field.
                 * @param field  the field to check, null returns false
                 * @return true if the field is supported on this era, false if not
                 */
                // @ts-ignore
                isSupported(field: java.time.temporal.TemporalField): boolean
                /**
                 * Gets the range of valid values for the specified field.
                 * <p>
                 * The range object expresses the minimum and maximum valid values for a field.
                 * This era is used to enhance the accuracy of the returned range.
                 * If it is not possible to return the range, because the field is not supported
                 * or for some other reason, an exception is thrown.
                 * <p>
                 * If the field is a {@link ChronoField} then the query is implemented here.
                 * The {@code ERA} field returns the range.
                 * All other {@code ChronoField} instances will throw an {@code UnsupportedTemporalTypeException}.
                 * <p>
                 * If the field is not a {@code ChronoField}, then the result of this method
                 * is obtained by invoking {@code TemporalField.rangeRefinedBy(TemporalAccessor)}
                 * passing {@code this} as the argument.
                 * Whether the range can be obtained is determined by the field.
                 * <p>
                 * The default implementation must return a range for {@code ERA} from
                 * zero to one, suitable for two era calendar systems such as ISO.
                 * @param field  the field to query the range for, not null
                 * @return the range of valid values for the field, not null
                 * @throws DateTimeException if the range for the field cannot be obtained
                 * @throws UnsupportedTemporalTypeException if the unit is not supported
                 */
                // @ts-ignore
                range(field: java.time.temporal.TemporalField): java.time.temporal.ValueRange
                /**
                 * Gets the value of the specified field from this era as an {@code int}.
                 * <p>
                 * This queries this era for the value of the specified field.
                 * The returned value will always be within the valid range of values for the field.
                 * If it is not possible to return the value, because the field is not supported
                 * or for some other reason, an exception is thrown.
                 * <p>
                 * If the field is a {@link ChronoField} then the query is implemented here.
                 * The {@code ERA} field returns the value of the era.
                 * All other {@code ChronoField} instances will throw an {@code UnsupportedTemporalTypeException}.
                 * <p>
                 * If the field is not a {@code ChronoField}, then the result of this method
                 * is obtained by invoking {@code TemporalField.getFrom(TemporalAccessor)}
                 * passing {@code this} as the argument. Whether the value can be obtained,
                 * and what the value represents, is determined by the field.
                 * @param field  the field to get, not null
                 * @return the value for the field
                 * @throws DateTimeException if a value for the field cannot be obtained or
                 *          the value is outside the range of valid values for the field
                 * @throws UnsupportedTemporalTypeException if the field is not supported or
                 *          the range of values exceeds an {#code int}
                 * @throws ArithmeticException if numeric overflow occurs
                 */
                // @ts-ignore
                get(field: java.time.temporal.TemporalField): number /*int*/
                /**
                 * Gets the value of the specified field from this era as a {@code long}.
                 * <p>
                 * This queries this era for the value of the specified field.
                 * If it is not possible to return the value, because the field is not supported
                 * or for some other reason, an exception is thrown.
                 * <p>
                 * If the field is a {@link ChronoField} then the query is implemented here.
                 * The {@code ERA} field returns the value of the era.
                 * All other {@code ChronoField} instances will throw an {@code UnsupportedTemporalTypeException}.
                 * <p>
                 * If the field is not a {@code ChronoField}, then the result of this method
                 * is obtained by invoking {@code TemporalField.getFrom(TemporalAccessor)}
                 * passing {@code this} as the argument. Whether the value can be obtained,
                 * and what the value represents, is determined by the field.
                 * @param field  the field to get, not null
                 * @return the value for the field
                 * @throws DateTimeException if a value for the field cannot be obtained
                 * @throws UnsupportedTemporalTypeException if the field is not supported
                 * @throws ArithmeticException if numeric overflow occurs
                 */
                // @ts-ignore
                getLong(field: java.time.temporal.TemporalField): number /*long*/
                /**
                 * Queries this era using the specified query.
                 * <p>
                 * This queries this era using the specified query strategy object.
                 * The {@code TemporalQuery} object defines the logic to be used to
                 * obtain the result. Read the documentation of the query to understand
                 * what the result of this method will be.
                 * <p>
                 * The result of this method is obtained by invoking the
                 * {@link TemporalQuery#queryFrom(TemporalAccessor)} method on the
                 * specified query passing {@code this} as the argument.
                 * @param <R> the type of the result
                 * @param query  the query to invoke, not null
                 * @return the query result, null may be returned (defined by the query)
                 * @throws DateTimeException if unable to query (defined by the query)
                 * @throws ArithmeticException if numeric overflow occurs (defined by the query)
                 */
                // @ts-ignore
                query<R>(query: java.time.temporal.TemporalQuery<R>): R
                /**
                 * Adjusts the specified temporal object to have the same era as this object.
                 * <p>
                 * This returns a temporal object of the same observable type as the input
                 * with the era changed to be the same as this.
                 * <p>
                 * The adjustment is equivalent to using {@link Temporal#with(TemporalField, long)}
                 * passing {@link ChronoField#ERA} as the field.
                 * <p>
                 * In most cases, it is clearer to reverse the calling pattern by using
                 * {@link Temporal#with(TemporalAdjuster)}:
                 * <pre>
                 * // these two lines are equivalent, but the second approach is recommended
                 * temporal = thisEra.adjustInto(temporal);
                 * temporal = temporal.with(thisEra);
                 * </pre>
                 * <p>
                 * This instance is immutable and unaffected by this method call.
                 * @param temporal  the target object to be adjusted, not null
                 * @return the adjusted object, not null
                 * @throws DateTimeException if unable to make the adjustment
                 * @throws ArithmeticException if numeric overflow occurs
                 */
                // @ts-ignore
                adjustInto(temporal: java.time.temporal.Temporal): java.time.temporal.Temporal
                /**
                 * Gets the textual representation of this era.
                 * <p>
                 * This returns the textual name used to identify the era,
                 * suitable for presentation to the user.
                 * The parameters control the style of the returned text and the locale.
                 * <p>
                 * If no textual mapping is found then the {@link #getValue() numeric value} is returned.
                 * @apiNote This default implementation is suitable for most implementations.
                 * @param style  the style of the text required, not null
                 * @param locale  the locale to use, not null
                 * @return the text value of the era, not null
                 */
                // @ts-ignore
                getDisplayName(style: java.time.format.TextStyle, locale: java.util.Locale): string
            }
        }
    }
}