Java tutorial
/* * This file is part of LuckPerms, licensed under the MIT License. * * Copyright (c) lucko (Luck) <luck@lucko.me> * Copyright (c) contributors * * Permission is hereby granted, free of charge, to any person obtaining a copy * of this software and associated documentation files (the "Software"), to deal * in the Software without restriction, including without limitation the rights * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell * copies of the Software, and to permit persons to whom the Software is * furnished to do so, subject to the following conditions: * * The above copyright notice and this permission notice shall be included in all * copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE * SOFTWARE. */ package me.lucko.luckperms.common.utils; import lombok.AllArgsConstructor; import lombok.experimental.UtilityClass; import com.github.benmanes.caffeine.cache.Caffeine; import com.github.benmanes.caffeine.cache.LoadingCache; import com.google.common.collect.Maps; import java.util.Map; import java.util.regex.Pattern; import java.util.regex.PatternSyntaxException; @UtilityClass public class PatternCache { private static final NullablePattern NULL_PATTERN = new NullablePattern(null); private static final LoadingCache<String, NullablePattern> CACHE = Caffeine.newBuilder().build(s -> { try { return new NullablePattern(Pattern.compile(s)); } catch (PatternSyntaxException e) { return NULL_PATTERN; } }); private static final LoadingCache<Map.Entry<String, String>, String> DELIMITER_CACHE = Caffeine.newBuilder() .build(e -> { // note the reversed order return "(?<!" + Pattern.quote(e.getValue()) + ")" + Pattern.quote(e.getKey()); }); public static Pattern compile(String regex) { return CACHE.get(regex).pattern; } public static String buildDelimitedMatcher(String delim, String esc) { return DELIMITER_CACHE.get(Maps.immutableEntry(delim, esc)); } public static Pattern compileDelimitedMatcher(String delim, String esc) { return compile(buildDelimitedMatcher(delim, esc)); } @AllArgsConstructor private static final class NullablePattern { private final Pattern pattern; } }