java-classic-code/java-commons-cache/impl/Redised.java

package com.primeton.dgs.kernel.core.cache.impl;

import com.primeton.dgs.kernel.core.cache.ICache;
import com.primeton.dgs.kernel.core.cache.serde.Serializer;
import com.primeton.dgs.kernel.core.cache.serde.JdkSerializer;
import com.primeton.dgs.kernel.core.cache.serde.StringSerializer;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import redis.clients.jedis.Jedis;

import java.io.IOException;
import java.io.Serializable;
import java.util.Set;

/**
 * <pre>
 *
 * Created by zhaopx.
 * User: zhaopx
 * Date: 2019/8/21
 * Time: 18:55
 *
 * </pre>
 *
 * @author zhaopx
 */
public class Redised implements ICache<Serializable> {


    private static Logger logger = LoggerFactory.getLogger(Redised.class);



    /**
     * Redis 的 Java Client
     */
    Jedis jedis;


    /**
     * redis db index
     */
    private final int db;

    /**
     * KEY 序列化
     */
    private final Serializer<String> KEY_SERDE = new StringSerializer();

    /**
     * Redis Cache 序列化方式
     */
    private final Serializer<Serializable> VALUE_SERDE = new JdkSerializer();


    public Redised() {
        this("localhost", 6379, 0);
    }


    public Redised(String host, int port){
        this(host, port, 0);
    }

    public Redised(String host, int port, int db){
        this.db = db;
        jedis = new Jedis(host, port);
        jedis.select(db);
    }

    @Override
    public void add(String key, Serializable value) {
        if(value == null) {
            return;
        }
        jedis.set(KEY_SERDE.serialize(key), VALUE_SERDE.serialize(value));
    }

    @Override
    public void add(String key, int exp, Serializable value) {
        byte[] keybytes = KEY_SERDE.serialize(key);
        jedis.set(keybytes, VALUE_SERDE.serialize(value));
        jedis.expire(keybytes, exp);
    }

    @Override
    public void replace(String key, Serializable value) {
        jedis.set(KEY_SERDE.serialize(key), VALUE_SERDE.serialize(value));
    }

    @Override
    public void replace(String key, int exp, Serializable value) {
        add(key, exp, value);
    }

    @Override
    public Serializable get(String key) {
        if(key == null) {
            return null;
        }
        byte[] bytes = jedis.get(KEY_SERDE.serialize(key));
        if(bytes == null) {
            return null;
        }
        return VALUE_SERDE.deserialize(bytes);
    }


    /**
     * 移除某条缓存
     * @param key 缓存的 KEY
     * @return
     */
    @Override
    public Serializable remove(String key) {
        if(key == null) {
            return null;
        }
        logger.info("remove cache key: {}", key);
        return jedis.del(KEY_SERDE.serialize(key));
    }


    @Override
    public int removeByPrefix(String prefix) {
        Set<String> keys = jedis.keys(prefix+"*");
        if(keys != null && keys.size() > 0) {
            for (String key : keys) {
                remove(key);
            }
        }
        return keys == null ? 0 : keys.size();
    }

    @Override
    public void clear() {
        jedis.flushDB();
    }

    @Override
    public int size() {
        return jedis.dbSize().intValue();
    }

    @Override
    public void close() throws IOException {
        jedis.close();
    }

    public static void main(String[] args) {
        Redised redis = new Redised("localhost", 6379);
        int size = redis.size();
        System.out.println(size);

        Set<String> keys = redis.jedis.keys("listMetadataTreeNode*");
        System.out.println(keys);
    }
}