[Add] 添加 ListCacheStore 的本地实现;

[Add] CopyOnWriteArrayListCacheStore 添加基于 CopyOnWriteArrayList 的 ListCacheStore 实现;
[Add] LocalCollectionCacheStore 添加集合型本地缓存存储容器父类, 已实现 CollectionCacheStore 接口;
[Add] ListCacheStoreTest 添加对 CopyOnWriteArrayListCacheStore 的完整单元测试(同样包括了 LocalCollectionCacheStore 的测试);

ContentGrabbingJi-CacheStore-local/src/main/java/net/lamgc/cgj/bot/cache/local/CopyOnWriteArrayListCacheStore.java

@@ -0,0 +1,91 @@
+/*
+ * Copyright (C) 2020  LamGC
+ *
+ * ContentGrabbingJi is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * ContentGrabbingJi is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package net.lamgc.cgj.bot.cache.local;
+
+import net.lamgc.cgj.bot.cache.ListCacheStore;
+
+import java.util.*;
+import java.util.concurrent.CopyOnWriteArrayList;
+
+/**
+ * 基于 {@link CopyOnWriteArrayList} 的有序列表缓存存储容器.
+ * @param <E> 元素类型.
+ * @author LamGC
+ */
+public class CopyOnWriteArrayListCacheStore<E> extends LocalCollectionCacheStore<E, List<E>> implements ListCacheStore<E> {
+
+    @Override
+    public E getElement(String key, int index) {
+        List<E> itemCollection = getCacheItemCollection(key, false);
+        try {
+            return itemCollection == null ? null : itemCollection.get(index);
+        } catch (IndexOutOfBoundsException e) {
+            return null;
+        }
+    }
+
+    @Override
+    public List<E> getElementsByRange(String key, int index, int length) {
+        int listLength = elementsLength(key);
+        if (listLength == -1) {
+            return null;
+        }
+        List<E> itemCollection = getCacheItemCollection(key, false);
+        List<E> result = new ArrayList<>();
+
+        try {
+            ListIterator<E> iterator = itemCollection.listIterator(index);
+            for (int i = 0; i < length && iterator.hasNext(); i++) {
+                result.add(iterator.next());
+            }
+        } catch (IndexOutOfBoundsException ignored) {
+            // 正常情况来讲, 该 try-catch 块只有 listIterator 会抛出 IndexOutOfBoundsException,
+            // 而一旦抛出 IndexOutOfBoundsException, 就代表 index 溢出了, try 块后面代码没有继续执行,
+            // 既然抛出异常时, result 并没有添加任何元素, 为何要再 new 一个 List 浪费内存呢? :D
+        }
+        return result;
+    }
+
+    @Override
+    public boolean removeElement(String key, int index) {
+        List<E> itemCollection = getCacheItemCollection(key, false);
+        if (itemCollection != null) {
+            try {
+                itemCollection.remove(index);
+                return true;
+            } catch (ArrayIndexOutOfBoundsException e) {
+                return false;
+            }
+        }
+        return false;
+    }
+
+    @Override
+    protected List<E> getCacheItemCollection(String key, boolean create) {
+        Objects.requireNonNull(key);
+        Map<String, CacheItem<List<E>>> cacheMap = getCacheMap();
+        if (!cacheMap.containsKey(key)) {
+            if (create) {
+                cacheMap.put(key, new CacheItem<>(new CopyOnWriteArrayList<>()));
+            } else {
+                return null;
+            }
+        }
+        return cacheMap.get(key).getValue();
+    }
+}

ContentGrabbingJi-CacheStore-local/src/main/java/net/lamgc/cgj/bot/cache/local/LocalCollectionCacheStore.java

@@ -0,0 +1,110 @@
+/*
+ * Copyright (C) 2020  LamGC
+ *
+ * ContentGrabbingJi is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * ContentGrabbingJi is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package net.lamgc.cgj.bot.cache.local;
+
+import net.lamgc.cgj.bot.cache.CollectionCacheStore;
+
+import java.util.Collection;
+import java.util.Objects;
+
+/**
+ * 本地集合缓存存储容器.
+ * @param <E> 元素类型
+ * @author LamGC
+ * @see net.lamgc.cgj.bot.cache.CacheStore
+ * @see net.lamgc.cgj.bot.cache.CollectionCacheStore
+ */
+public abstract class LocalCollectionCacheStore<E, C extends Collection<E>>
+extends HashCacheStore<C>
+implements CollectionCacheStore<E, C> {
+
+    /**
+     * 获取缓存项集合对象.
+     * @param key 缓存项键名
+     * @param create 如果不存在, 是否创建.
+     * @return 如果不存在且 create 为 false, 或添加失败, 返回 false, 添加成功返回 true.
+     */
+    protected abstract C getCacheItemCollection(String key, boolean create);
+
+    @Override
+    public boolean addElement(String key, E element) {
+        Objects.requireNonNull(key);
+        Objects.requireNonNull(element);
+        Collection<E> itemCollection = getCacheItemCollection(key, true);
+        return itemCollection.add(element);
+    }
+
+    @Override
+    public boolean addElements(String key, Collection<E> elements) {
+        Objects.requireNonNull(key);
+        Objects.requireNonNull(elements);
+        Collection<E> itemCollection = getCacheItemCollection(key, true);
+        return itemCollection.addAll(elements);
+    }
+
+    @Override
+    public boolean containsElement(String key, E value) {
+        Objects.requireNonNull(key);
+        Objects.requireNonNull(value);
+        Collection<E> itemCollection = getCacheItemCollection(key, false);
+        if (itemCollection == null) {
+            return false;
+        }
+        return itemCollection.contains(value);
+    }
+
+    @Override
+    public boolean isEmpty(String key) {
+        Collection<E> itemCollection = getCacheItemCollection(Objects.requireNonNull(key), false);
+        if (itemCollection == null) {
+            return false;
+        }
+        return itemCollection.isEmpty();
+    }
+
+    @Override
+    public int elementsLength(String key) {
+        Collection<E> itemCollection = getCacheItemCollection(Objects.requireNonNull(key), false);
+        if (itemCollection == null) {
+            return -1;
+        }
+        return itemCollection.size();
+    }
+
+    @Override
+    public boolean clearCollection(String key) {
+        Collection<E> itemCollection = getCacheItemCollection(Objects.requireNonNull(key), false);
+        if (itemCollection == null) {
+            return false;
+        }
+        itemCollection.clear();
+        return true;
+    }
+
+    @Override
+    public boolean removeElement(String key, E element) {
+        Objects.requireNonNull(key);
+        Objects.requireNonNull(element);
+        Collection<E> itemCollection = getCacheItemCollection(key, false);
+        if (itemCollection == null) {
+            return false;
+        }
+        return itemCollection.remove(element);
+    }
+
+}