创建一个可以设置过期时间的hashMap

package cn.com.servyou.sbf.api.client.cxjm;

import java.io.Serializable;
import java.util.*;

/**
 * <pre>类名: ExpiryMap</pre>
 * <pre>描述: 可以设置过期时间的hashMap</pre>
 * <pre>版权: 税友软件集团股份有限公司</pre>
 * <pre>日期: 2019/12/12 11:13</pre>
 * <pre>Author: liangbl</pre>
 */
public class ExpiryMap<K, V> extends HashMap<K, V> implements Serializable {

    private static final long serialVersionUID = 2515949650733901306L;

    /**
     * 过期时间设置为4小时，可以修改
     */
    private long EXPIRY = 1000 * 60 * 60 * 4;

    private HashMap<K, Long> expiryMap = new HashMap<K, Long>();

    public ExpiryMap() {
        super();
    }

    public ExpiryMap(long defaultExpiryTime) {
        this(1 << 4, defaultExpiryTime);
    }

    public ExpiryMap(int initialCapacity, long defaultExpiryTime) {
        super(initialCapacity);
        this.EXPIRY = defaultExpiryTime;
    }

    @Override
    public V put(K key, V value) {
        expiryMap.put(key, System.currentTimeMillis() + EXPIRY);
        return super.put(key, value);
    }

    @Override
    public boolean containsKey(Object key) {
        return !checkExpiry(key, true) && super.containsKey(key);
    }

    /**
     * @param key
     * @param value
     * @param expiryTime 键值对有效期 毫秒
     * @return
     */
    public V put(K key, V value, long expiryTime) {
        expiryMap.put(key, System.currentTimeMillis() + expiryTime);
        return super.put(key, value);
    }

    @Override
    public int size() {
        return entrySet().size();
    }

    @Override
    public boolean isEmpty() {
        return entrySet().size() == 0;
    }

    @Override
    public boolean containsValue(Object value) {
        if (value == null) {
            return Boolean.FALSE;
        }

        Set<Map.Entry<K, V>> set = super.entrySet();
        Iterator<Map.Entry<K, V>> iterator = set.iterator();
        while (iterator.hasNext()) {
            Map.Entry<K, V> entry = iterator.next();
            if (value.equals(entry.getValue())) {
                if (checkExpiry(entry.getKey(), false)) {
                    iterator.remove();
                    return Boolean.FALSE;
                } else {
                    return Boolean.TRUE;
                }

            }
        }
        return Boolean.FALSE;
    }

    @Override
    public Collection<V> values() {

        Collection<V> values = super.values();

        if (values == null || values.size() < 1) {
            return values;
        }

        Iterator<V> iterator = values.iterator();

        while (iterator.hasNext()) {
            V next = iterator.next();
            if (!containsValue(next)) {
                iterator.remove();
            }
        }
        return values;
    }

    @Override
    public V get(Object key) {
        if (key == null) {
            return null;
        }

        if (checkExpiry(key, true)) {
            return null;
        }

        return super.get(key);
    }

    /**
     * @param key
     * @return null:不存在或key为null -1:过期 存在且没过期返回value 因为过期的不是实时删除，所以稍微有点作用
     * @Description: 是否过期
     */
    public Object isInvalid(Object key) {
        if (key == null) {
            return null;
        }

        if (!expiryMap.containsKey(key)) {
            return null;
        }
        long expiryTime = expiryMap.get(key);

        boolean flag = System.currentTimeMillis() > expiryTime;

        if (flag) {
            super.remove(key);
            expiryMap.remove(key);
            return -1;
        }
        return super.get(key);
    }

    @Override
    public void putAll(Map<? extends K, ? extends V> m) {
        for (Map.Entry<? extends K, ? extends V> e : m.entrySet()) {
            expiryMap.put(e.getKey(), System.currentTimeMillis() + EXPIRY);
        }
        super.putAll(m);
    }

    @Override
    public Set<Map.Entry<K, V>> entrySet() {
        Set<Map.Entry<K, V>> set = super.entrySet();
        Iterator<Map.Entry<K, V>> iterator = set.iterator();
        while (iterator.hasNext()) {
            Map.Entry<K, V> entry = iterator.next();
            if (checkExpiry(entry.getKey(), false)) {
                iterator.remove();
            }
        }
        return set;
    }

    /**
     * @param isRemoveSuper true super删除
     * @return
     * @Description: 是否过期
     */
    private boolean checkExpiry(Object key, boolean isRemoveSuper) {

        if (!expiryMap.containsKey(key)) {
            return Boolean.FALSE;
        }
        long expiryTime = expiryMap.get(key);

        boolean flag = System.currentTimeMillis() > expiryTime;

        if (flag) {
            if (isRemoveSuper) {
                super.remove(key);
            }
            expiryMap.remove(key);
        }
        return flag;
    }

    public static void main(String[] args) throws InterruptedException {

        ExpiryMap<String, String> map = new ExpiryMap<String, String>(10);
        map.put("test", "ankang");
        map.put("test1", "ankang");
        map.put("test2", "ankang", 3000);
        System.out.println("test1" + map.get("test"));
        Thread.sleep(1000);
        System.out.println("isInvalid:" + map.isInvalid("test"));
        System.out.println("size:" + map.size());
        System.out.println("size:" + ((HashMap<String, String>) map).size());
        for (Map.Entry<String, String> m : map.entrySet()) {
            System.out.println("isInvalid:" + map.isInvalid(m.getKey()));
            map.containsKey(m.getKey());
            System.out.println("key:" + m.getKey() + "     value:" + m.getValue());
        }
        System.out.println("test1" + map.get("test"));

    }

}