CaseInsensitiveContainerFactory.java

/**
 * Copyright (c) 2011-2013, James Zhan 詹波 (jfinal@126.com).
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package net.tooan.ynpay.third.jfinal.plugin.activerecord;

import java.util.HashMap;
import java.util.HashSet;
import java.util.Map;
import java.util.Set;

@SuppressWarnings({"rawtypes", "unchecked"})
public class CaseInsensitiveContainerFactory implements IContainerFactory {

    private static boolean toLowerCase = false;

    public CaseInsensitiveContainerFactory() {
    }

    public CaseInsensitiveContainerFactory(boolean toLowerCase) {
        CaseInsensitiveContainerFactory.toLowerCase = toLowerCase;
    }

    public Map<String, Object> getAttrsMap() {
        return new CaseInsensitiveMap();
    }

    public Map<String, Object> getColumnsMap() {
        return new CaseInsensitiveMap();
    }

    public Set<String> getModifyFlagSet() {
        return new CaseInsensitiveSet();
    }

    private static Object convertCase(Object key) {
        if (key instanceof String)
            return toLowerCase ? ((String) key).toLowerCase() : ((String) key).toUpperCase();
        return key;
    }

    /*
     * 1：非静态内部类拥有对外部类的所有成员的完全访问权限，包括实例字段和方法，
     *    为实现这一行为，非静态内部类存储着对外部类的实例的一个隐式引用
     * 2：序列化时要求所有的成员变量是Serializable 包括上面谈到的引式引用
     * 3：外部类CaseInsensitiveContainerFactory 需要 implements Serializable 才能被序列化
     * 4：可以使用静态内部类来实现内部类的序列化，而非让外部类实现 implements Serializable
     */
    public static class CaseInsensitiveSet extends HashSet {

        private static final long serialVersionUID = 102410961064096233L;

        public boolean add(Object e) {
            return super.add(convertCase(e));
        }

        public boolean remove(Object e) {
            return super.remove(convertCase(e));
        }

        public boolean contains(Object e) {
            return super.contains(convertCase(e));
        }
    }

    public static class CaseInsensitiveMap extends HashMap {

        private static final long serialVersionUID = 6843981594457576677L;

        public Object get(Object key) {
            return super.get(convertCase(key));
        }

        public boolean containsKey(Object key) {
            return super.containsKey(convertCase(key));
        }

        public Object put(Object key, Object value) {
            return super.put(convertCase(key), value);
        }

        public void putAll(Map m) {
            for (Map.Entry e : (Set<Map.Entry>) (m.entrySet()))
                put(e.getKey(), e.getValue());
        }

        public Object remove(Object key) {
            return super.remove(convertCase(key));
        }
    }
}