org.microbean.microprofile.config

Class ConfigSourceComparator

java.lang.Object

org.microbean.microprofile.config.ConfigSourceComparator

All Implemented Interfaces:

Comparator<ConfigSource>

public final class ConfigSourceComparator
extends Object
implements Comparator<ConfigSource>

A Comparator of ConfigSources that considers only their ordinals and names in accordance with the minimal requirements of the MicroProfile Config specification as spelled out (only) in the ConfigSource API documentation.

This Comparator implementation is, and must be, inconsistent with equals(), as implied by the same specification.

Note that the requirement to use a ConfigSource's name as a secondary sorting key is defined only in the javadocs of the ConfigSource.getOrdinal() method.

Note further that there are no guidelines or requirements about what format a ConfigSource's name must take, so in effect the ordering of two ConfigSources that have a common ordinal is undefined.

Author:

Laird Nelson

See Also:

compare(ConfigSource, ConfigSource), ConfigSource, ConfigSource.getOrdinal(), ConfigSource.getName()

Field Summary

Fields

Modifier and Type	Field and Description
static ConfigSourceComparator	INSTANCE The sole instance of this class.

Method Summary

Modifier and Type	Method and Description
int	compare(ConfigSource firstConfigSource, ConfigSource secondConfigSource) Compares two ConfigSources, returning -1 if the first has an ordinal greater than that of the second and 1 if the second has an ordinal greater than that of the first, and then the result of invoking String.compareTo(String) on the return values of the ConfigSources' respective ConfigSource.getName() methods.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface java.util.Comparator

comparing, comparing, comparingDouble, comparingInt, comparingLong, equals, naturalOrder, nullsFirst, nullsLast, reversed, reverseOrder, thenComparing, thenComparing, thenComparing, thenComparingDouble, thenComparingInt, thenComparingLong

Field Detail

INSTANCE

public static final ConfigSourceComparator INSTANCE

The sole instance of this class.

Method Detail

compare

public final int compare(ConfigSource firstConfigSource,
                         ConfigSource secondConfigSource)

Compares two ConfigSources, returning -1 if the first has an ordinal greater than that of the second and 1 if the second has an ordinal greater than that of the first, and then the result of invoking String.compareTo(String) on the return values of the ConfigSources' respective ConfigSource.getName() methods.

This method may return 0 when both ConfigSources are not otherwise semantically equal.

Specified by:

compare in interface Comparator<ConfigSource>

Parameters:

firstConfigSource - the first of two ConfigSources; may be null

secondConfigSource - the second of two ConfigSources; may be null

Returns:

-1 if the first ConfigSource has an ordinal greater than that of the second, 1 if the second ConfigSource has an ordinal greater than that of the first, and the result of invoking String.compareTo(String) on the return values of the ConfigSources' respective ConfigSource.getName() methods otherwise

See Also:

ConfigSource, ConfigSource.getName(), ConfigSource.getOrdinal()