• Java 中常用缓存Cache机制的实现


    Java 中常用缓存Cache机制的实现

     

    所谓缓存,就是将程序或系统经常要调用的对象存在内存中,一遍其使用时可以快速调用,不必再去创建新的重复的实例。这样做可以减少系统开销,提高系统效率。

    所谓缓存,就是将程序或系统经常要调用的对象存在内存中,一遍其使用时可以快速调用,不必再去创建新的重复的实例。这样做可以减少系统开销,提高系统效率。

    缓存主要可分为二大类: 

    一、通过文件缓存,顾名思义文件缓存是指把数据存储在磁盘上,不管你是以XML格式,序列化文件DAT格式还是其它文件格式;  

    二、内存缓存,也就是实现一个类中静态Map,对这个Map进行常规的增删查. 

    代码如下:

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    package lhm.hcy.guge.frameset.cache;
      
    import java.util.*;
      
     //Description: 管理缓存
      
     //可扩展的功能:当chche到内存溢出时必须清除掉最早期的一些缓存对象,这就要求对每个缓存对象保存创建时间
      
    public class CacheManager {
        private static HashMap cacheMap = new HashMap();
      
        //单实例构造方法
        private CacheManager() {
            super();
        }
        //获取布尔值的缓存
        public static boolean getSimpleFlag(String key){
            try{
                return (Boolean) cacheMap.get(key);
            }catch(NullPointerException e){
                return false;
            }
        }
        public static long getServerStartdt(String key){
            try {
                return (Long)cacheMap.get(key);
            catch (Exception ex) {
                return 0;
            }
        }
        //设置布尔值的缓存
        public synchronized static boolean setSimpleFlag(String key,boolean flag){
            if (flag && getSimpleFlag(key)) {//假如为真不允许被覆盖
                return false;
            }else{
                cacheMap.put(key, flag);
                return true;
            }
        }
        public synchronized static boolean setSimpleFlag(String key,long serverbegrundt){
            if (cacheMap.get(key) == null) {
                cacheMap.put(key,serverbegrundt);
                return true;
            }else{
                return false;
            }
        }
      
      
        //得到缓存。同步静态方法
        private synchronized static Cache getCache(String key) {
            return (Cache) cacheMap.get(key);
        }
      
        //判断是否存在一个缓存
        private synchronized static boolean hasCache(String key) {
            return cacheMap.containsKey(key);
        }
      
        //清除所有缓存
        public synchronized static void clearAll() {
            cacheMap.clear();
        }
      
        //清除某一类特定缓存,通过遍历HASHMAP下的所有对象,来判断它的KEY与传入的TYPE是否匹配
        public synchronized static void clearAll(String type) {
            Iterator i = cacheMap.entrySet().iterator();
            String key;
            ArrayList arr = new ArrayList();
            try {
                while (i.hasNext()) {
                    java.util.Map.Entry entry = (java.util.Map.Entry) i.next();
                    key = (String) entry.getKey();
                    if (key.startsWith(type)) { //如果匹配则删除掉
                        arr.add(key);
                    }
                }
                for (int k = 0; k < arr.size(); k++) {
                    clearOnly(arr.get(k));
                }
            catch (Exception ex) {
                ex.printStackTrace();
            }
        }
      
        //清除指定的缓存
        public synchronized static void clearOnly(String key) {
            cacheMap.remove(key);
        }
      
        //载入缓存
        public synchronized static void putCache(String key, Cache obj) {
            cacheMap.put(key, obj);
        }
      
        //获取缓存信息
        public static Cache getCacheInfo(String key) {
      
            if (hasCache(key)) {
                Cache cache = getCache(key);
                if (cacheExpired(cache)) { //调用判断是否终止方法
                    cache.setExpired(true);
                }
                return cache;
            }else
                return null;
        }
      
        //载入缓存信息
        public static void putCacheInfo(String key, Cache obj, long dt,boolean expired) {
            Cache cache = new Cache();
            cache.setKey(key);
            cache.setTimeOut(dt + System.currentTimeMillis()); //设置多久后更新缓存
            cache.setValue(obj);
            cache.setExpired(expired); //缓存默认载入时,终止状态为FALSE
            cacheMap.put(key, cache);
        }
        //重写载入缓存信息方法
        public static void putCacheInfo(String key,Cache obj,long dt){
            Cache cache = new Cache();
            cache.setKey(key);
            cache.setTimeOut(dt+System.currentTimeMillis());
            cache.setValue(obj);
            cache.setExpired(false);
            cacheMap.put(key,cache);
        }
      
        //判断缓存是否终止
        public static boolean cacheExpired(Cache cache) {
            if (null == cache) { //传入的缓存不存在
                return false;
            }
            long nowDt = System.currentTimeMillis(); //系统当前的毫秒数
            long cacheDt = cache.getTimeOut(); //缓存内的过期毫秒数
            if (cacheDt <= 0||cacheDt>nowDt) { //过期时间小于等于零时,或者过期时间大于当前时间时,则为FALSE
                return false;
            else //大于过期时间 即过期
                return true;
            }
        }
      
        //获取缓存中的大小
        public static int getCacheSize() {
            return cacheMap.size();
        }
      
        //获取指定的类型的大小
        public static int getCacheSize(String type) {
            int k = 0;
            Iterator i = cacheMap.entrySet().iterator();
            String key;
            try {
                while (i.hasNext()) {
                    java.util.Map.Entry entry = (java.util.Map.Entry) i.next();
                    key = (String) entry.getKey();
                    if (key.indexOf(type) != -1) { //如果匹配则删除掉
                        k++;
                    }
                }
            catch (Exception ex) {
                ex.printStackTrace();
            }
      
            return k;
        }
      
        //获取缓存对象中的所有键值名称
        public static ArrayList getCacheAllkey() {
            ArrayList a = new ArrayList();
            try {
                Iterator i = cacheMap.entrySet().iterator();
                while (i.hasNext()) {
                    java.util.Map.Entry entry = (java.util.Map.Entry) i.next();
                    a.add((String) entry.getKey());
                }
            catch (Exception ex) {} finally {
                return a;
            }
        }
      
        //获取缓存对象中指定类型 的键值名称
        public static ArrayList getCacheListkey(String type) {
            ArrayList a = new ArrayList();
            String key;
            try {
                Iterator i = cacheMap.entrySet().iterator();
                while (i.hasNext()) {
                    java.util.Map.Entry entry = (java.util.Map.Entry) i.next();
                    key = (String) entry.getKey();
                    if (key.indexOf(type) != -1) {
                        a.add(key);
                    }
                }
            catch (Exception ex) {} finally {
                return a;
            }
        }
      
    }
      
      
    package lhm.hcy.guge.frameset.cache;
      
    public class Cache {
            private String key;//缓存ID
            private Object value;//缓存数据
            private long timeOut;//更新时间
            private boolean expired; //是否终止
            public Cache() {
                    super();
            }
      
            public Cache(String key, Object value, long timeOut, boolean expired) {
                    this.key = key;
                    this.value = value;
                    this.timeOut = timeOut;
                    this.expired = expired;
            }
      
            public String getKey() {
                    return key;
            }
      
            public long getTimeOut() {
                    return timeOut;
            }
      
            public Object getValue() {
                    return value;
            }
      
            public void setKey(String string) {
                    key = string;
            }
      
            public void setTimeOut(long l) {
                    timeOut = l;
            }
      
            public void setValue(Object object) {
                    value = object;
            }
      
            public boolean isExpired() {
                    return expired;
            }
      
            public void setExpired(boolean b) {
                    expired = b;
            }
    }
      
    //测试类,
    class Test {
        public static void main(String[] args) {
            System.out.println(CacheManager.getSimpleFlag("alksd"));
    //        CacheManager.putCache("abc", new Cache());
    //        CacheManager.putCache("def", new Cache());
    //        CacheManager.putCache("ccc", new Cache());
    //        CacheManager.clearOnly("");
    //        Cache c = new Cache();
    //        for (int i = 0; i < 10; i++) {
    //            CacheManager.putCache("" + i, c);
    //        }
    //        CacheManager.putCache("aaaaaaaa", c);
    //        CacheManager.putCache("abchcy;alskd", c);
    //        CacheManager.putCache("cccccccc", c);
    //        CacheManager.putCache("abcoqiwhcy", c);
    //        System.out.println("删除前的大小:"+CacheManager.getCacheSize());
    //        CacheManager.getCacheAllkey();
    //        CacheManager.clearAll("aaaa");
    //        System.out.println("删除后的大小:"+CacheManager.getCacheSize());
    //        CacheManager.getCacheAllkey();
      
      
        }
    }

    spring中的redis service实现

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    package com.eshore.ismp.cache.redis;
     
    import java.io.UnsupportedEncodingException;
    import java.util.ArrayList;
    import java.util.Collection;
    import java.util.Collections;
    import java.util.HashSet;
    import java.util.List;
    import java.util.Map;
    import java.util.Map.Entry;
    import java.util.Set;
     
    import org.springframework.beans.factory.annotation.Autowired;
    import org.springframework.dao.DataAccessException;
    import org.springframework.data.redis.connection.RedisConnection;
    import org.springframework.data.redis.core.RedisCallback;
    import org.springframework.data.redis.core.RedisTemplate;
    import org.springframework.stereotype.Service;
     
    @Service
    public class RedisService {
     
        private static String redisCode = "utf-8";
         
        @Autowired
        private RedisTemplate<String, String> redisTemplate;
     
        /**
         * 从指定的列表右边出队,添加到目的列表中
         *
         * @param srckey
         *            源列表
         * @param dstkey
         *             目的列表
         * @return
         */
        public String rpoppush(final String srckey, final String dstkey) {
            return redisTemplate.execute(new RedisCallback<String>() {
                public String doInRedis(RedisConnection connection)
                        throws DataAccessException {
                    try {
                        return new String (connection.rPopLPush(srckey.getBytes(), dstkey.getBytes()), redisCode);
                    catch (UnsupportedEncodingException e) {
                        e.printStackTrace();
                    }
                    return "";
                }
            });
        }
        /**
         * 获取指定列表的范围数据
         *
         * @param key
         *             列表名
         * @param start
         *             开始位置
         * @param end
         *             结束位置
         * @return
         */
        public List<String> lrange(final String key, final int start, final int end) {
            return redisTemplate.execute(new RedisCallback<List<String>>() {
                List<String> result = new ArrayList<String>();
                public List<String> doInRedis(RedisConnection connection)
                        throws DataAccessException {
                    List<byte[]> bytelist= connection.lRange(key.getBytes(), start, end);
                    for (byte[] b : bytelist) {
                        try {
                            result.add(new String(b, redisCode));
                        catch (UnsupportedEncodingException e) {
                            e.printStackTrace();
                        }
                    }
                    return result;
                }
            });
        }
        /**
         * 从队列的左边取出一条数据
         *
         * @param key
         *             列表名
         * @return
         */
        public String lpop(final String key) {
            return redisTemplate.execute(new RedisCallback<String>() {
                public String doInRedis(RedisConnection connection)
                        throws DataAccessException {
                    byte[] result = connection.lPop(key.getBytes());
                    if (result != null) {
                        try {
                            return new String (result , redisCode);
                        catch (UnsupportedEncodingException e) {
                            e.printStackTrace();
                        }
                    }
                    return "";
                }
            });
        }
         
        /**
         * 从队列的左边取出一条数据
         *
         * @param key
         *             列表名
         * @return
         */
        public List<?> lpop(final String key,final int size) {
            List<Object> list =  redisTemplate.executePipelined(new RedisCallback<List<Object>>() {
                public List<Object> doInRedis(RedisConnection connection)
                        throws DataAccessException {
                    byte[] keyBytes = key.getBytes();
                    for(int i =0 ; i< size; i++){
                        connection.lPop(keyBytes);
                    }
                    return null;
                }
            });
            list.removeAll(Collections.singleton(null));
            return list;
        }
         
        /**
         * 从列表右边添加数据
         *
         * @param key
         *            列表名
         * @param values
         *            数据
         * @return
         */
        public long rpush(final String key, final String... values) {
            return redisTemplate.execute(new RedisCallback<Long>() {
                public Long doInRedis(RedisConnection connection)
                        throws DataAccessException {
                    long result = 0;
                    for (String v : values) {
                        result = connection.rPush(key.getBytes(), v.getBytes());
                    }
                    return result;
                }
            });
        }
         
        /**
         * 从列表右边添加数据
         *
         * @param key
         *            列表名
         * @param values
         *            数据
         * @return
         */
        public long rpush(final String key, final Collection<String> values) {
            return redisTemplate.opsForList().rightPushAll(key, values);
        }
         
        public int hmset(final String key, final Map<String,String> values) {
            try{
             redisTemplate.opsForHash().putAll(key, values);
            }catch(Exception e){
                e.printStackTrace();
                return -1;
            }
            return 0 ;
        }
        public String hget(final String key, final String field){
            Object obj =redisTemplate.opsForHash().get(key, field);
            return String.valueOf(obj);
        }
         
        public List<?> hkeys(final String key){
            return redisTemplate.execute(new RedisCallback<List<Object>>(){
                List<Object> list = new ArrayList<Object>();
                public List<Object> doInRedis(RedisConnection connection)
                        throws DataAccessException {
                    Set<byte[]> sets=connection.hKeys(key.getBytes());
                    if(!sets.isEmpty()){
                        for(byte[] b : sets){
                            list.add(redisTemplate.getValueSerializer().deserialize(b).toString());
                        }
                        return list;
                    }
                    return null;
                }
            });
        }
         
        /**
         * 删除hash表中field
         */
        public void hdel(final String key,final String field){
            redisTemplate.opsForHash().delete(key, field);
        }
        /**
         * 从列表右边添加数据,并且设置列表的存活时间
         *
         * @param key
         *            列表名
         * @param liveTime
         *            存活时间(单位 秒)
         * @param values
         *            数据
         * @return
         */
        public long rpush(final String key, final int liveTime, final String... values) {
            return redisTemplate.execute(new RedisCallback<Long>() {
                public Long doInRedis(RedisConnection connection)
                        throws DataAccessException {
                    long result = 0;
                    for (String v : values) {
                        connection.rPush(key.getBytes(), v.getBytes());
                    }
                    if (liveTime > 0) {
                        connection.expire(key.getBytes(), liveTime);
                    }  
                    return result;
                }
            });
        }
        /**
         * 从队列的右边取出一条数据
         *
         * @param key
         *            列表名
         * @return
         */
        public String rpop(final String key) {
            return redisTemplate.execute(new RedisCallback<String>() {
                public String doInRedis(RedisConnection connection)
                        throws DataAccessException {
                    byte[] result = connection.rPop(key.getBytes());
                    if(result != null ){
                        try {
                            return new String (result, redisCode);
                        catch (UnsupportedEncodingException e) {
                            e.printStackTrace();
                        }
                    }
                    return "";
                }
            });
        }
        /**
         * 把一个值添加到对应列表中
         *
         * @param key
         *            列表名
         * @param index
         *             添加的位置
         * @param value
         *             数据
         * @return
         */
        public String lset(final String key, final long index, final String value) {
            return redisTemplate.execute(new RedisCallback<String>() {
                public String doInRedis(RedisConnection connection)
                        throws DataAccessException {
                    connection.lSet(key.getBytes(), index, value.getBytes());
                    return "success";
                }
            });
        }
        /**
         * 把所有数据添加到一个列表中
         *
         * @param key
         *            列表名
         * @param values
         *             数据
         * @return
         */
        public long lpush(String key, String... values) {
            return this.lpush(key, 0, values);
        }
        /**
         * 把所有数据添加到一个列表中,并且设置列表的存活时间
         *
         * @param key
         *            列表名
         * @param values
         *            数据
         * @param liveTime
         *            存活时间--单位(秒)
         * @return
         */
        public long lpush(final String key,final  int liveTime, final String... values) {
            return redisTemplate.execute(new RedisCallback<Long>() {
                public Long doInRedis(RedisConnection connection)
                        throws DataAccessException {
                    long result = 0;
                    for (String v : values){
                        result = connection.lPush(key.getBytes(), v.getBytes());
                    }
                    if (liveTime > 0) {
                        connection.expire(key.getBytes(), liveTime);
                    }
                    return result;
                }
            });
        }
        /**
         * 返回列表的长度
         *
         * @param key
         * @return
         */
        public long llen(final String key) {
            return redisTemplate.execute(new RedisCallback<Long>() {
                public Long doInRedis(RedisConnection connection)
                        throws DataAccessException {
                    return connection.lLen(key.getBytes());
                }
            });
        }
        /**
         * 删除列表中对应值的元素
         *
         * @param key
         *            列表名
         * @param count
         *            删除多少个相同的元素
         * @param value
         *            数据
         * @return
         */
        public long lrem(final String key, final long count, final String value) {
            return redisTemplate.execute(new RedisCallback<Long>() {
                public Long doInRedis(RedisConnection connection)
                        throws DataAccessException {
                    return connection.lRem(key.getBytes(), count, value.getBytes());
                }
            });
        }
        /**
         * 通过keys批量删除
         *
         * @param key
         */
        public long del(final String... keys) {
            return redisTemplate.execute(new RedisCallback<Long>() {
                public Long doInRedis(RedisConnection connection)
                        throws DataAccessException {
                    long result = 0;
                    for (String k : keys) {
                        result = connection.del(k.getBytes());
                    }
                    return result;
                }
            });
        }
         
        /**
         *
         * //DESC 删除单个key
         * @time: 2016年5月27日 上午9:00:36
         * @param key
         * @return
         * @throws
         */
        public long del(final String key){
            return redisTemplate.execute(new RedisCallback<Long>(){
                @Override
                public Long doInRedis(RedisConnection connection)
                        throws DataAccessException {
                    return connection.del(key.getBytes());
                }
                 
            });
        }
         
         
        /**
         * 添加key value 并且设置存活时间(byte)
         *
         * @param key
         * @param value
         * @param liveTime
         */
        public void set(final byte[] key, final byte[] value, final long liveTime) {
            redisTemplate.execute(new RedisCallback<Long>() {
                public Long doInRedis(RedisConnection connection)
                        throws DataAccessException {
                    connection.set(key, value);
                    if (liveTime > 0) {
                        connection.expire(key, liveTime);
                    }
                    return 1L;
                }
            });
             
        }
        /**
         * 添加key value 并且设置存活时间
         *
         * @param key
         * @param value
         * @param liveTime
         *            单位秒
         */
        public void set(String key, String value, long liveTime) {
            this.set(key.getBytes(), value.getBytes(), liveTime);
             
        }
        /**
         * 添加key value
         *
         * @param key
         * @param value
         */
        public void set(String key, String value) {
            this.set(key, value, 0L);
        }
         
        /**
         * 添加key value
         *
         * @param key
         * @param value
         */
        public void setMulti(final Map<String,String> map) {
            setMulti(map,0L);
        }
         
        /**
         * 添加key value
         *
         * @param key
         * @param value
         */
        public void setMulti(final Map<String,String> map,final long liveTime) {
             redisTemplate.executePipelined(new RedisCallback<String>() {
                public String doInRedis(RedisConnection connection)
                        throws DataAccessException {
                    Set<Map.Entry<String, String >> set = map.entrySet();
                    for (Entry<String, String> entry : set) {
                        connection.set(entry.getKey().getBytes(), entry.getValue().getBytes());
                        if (liveTime > 0) {
                            connection.expire(entry.getKey().getBytes(), liveTime);
                        }
                    }
                    return null;
                }
            });
        }
        /**
         * 添加key value (字节)(序列化)
         *
         * @param key
         * @param value
         */
        public void set(byte[] key, byte[] value) {
            this.set(key, value, 0L);
             
        }
        /**
         * 获取redis value (String)
         *
         * @param key
         * @return
         */
        public String get(final String key) {
            return redisTemplate.execute(new RedisCallback<String>() {
                public String doInRedis(RedisConnection connection)
                        throws DataAccessException {
                byte[] result = connection.get(key.getBytes());
                if (result != null) {
                    try {
                        return new String (result ,redisCode);
                    catch (UnsupportedEncodingException e) {
                        e.printStackTrace();
                    }  
                }
                return "";
                }
            });
        }
        /**
         * 如果key不存在添加key value 并且设置存活时间(byte),当key已经存在时,就不做任何操作
         *
         * @param key
         * @param value
         * @param liveTime
         */
        public long setnx(final byte[] key, final byte[] value, final long liveTime) {
            return redisTemplate.execute(new RedisCallback<Long>() {
                public Long doInRedis(RedisConnection connection)
                        throws DataAccessException {
                    long result = 0l;
                    boolean isSuccess = connection.setNX(key, value);
                    if (isSuccess) {
                        if (liveTime > 0) {
                            connection.expire(key, liveTime);
                        }
                        result = 1l;
                    }
                    return result;
                }
            });
        }
        /**
         * 如果key不存在添加key value 并且设置存活时间,当key已经存在时,就不做任何操作
         *
         * @param key
         * @param value
         * @param liveTime
         *            单位秒
         */
        public long setnx(String key, String value, long liveTime) {
            return this.setnx(key.getBytes(), value.getBytes(), liveTime);
             
        }
        /**
         * 如果key不存在添加key value,当key已经存在时,就不做任何操作
         *
         * @param key
         * @param value
         */
        public long setnx(String key, String value) {
            return this.setnx(key, value, 0L);
        }
        /**
         * 如果key不存在添加key value (字节)(序列化),当key已经存在时,就不做任何操作
         *
         * @param key
         * @param value
         */
        public long setnx(byte[] key, byte[] value) {
            return this.setnx(key, value, 0L);
             
        }
        /**
         * 通过正则匹配keys
         *
         * @param pattern
         * @return
         */
        public Set<String> keys(final String pattern) {
            return redisTemplate.execute(new RedisCallback<Set<String>>() {
                public Set<String> doInRedis(RedisConnection connection)
                        throws DataAccessException {
                Set<String> result = new HashSet<String>();
                Set<byte[]>   data = connection.keys(pattern.getBytes());
                for(byte[] d : data){
                    try {
                        result.add(new String(d,redisCode));
                    catch (UnsupportedEncodingException e) {
                        e.printStackTrace();
                    }
                }
                return result;
                }
            });
        }
        /**
         * 检查key是否已经存在
         *
         * @param key
         * @return
         */
        public boolean exists(final String key) {
            return redisTemplate.execute(new RedisCallback<Boolean>() {
                public Boolean doInRedis(RedisConnection connection)
                        throws DataAccessException {
                    return connection.exists(key.getBytes());
                }
                 
            });
        }
        /**
         * 清空redis 所有数据
         *
         * @return
         */
        public String flushDB() {
            return redisTemplate.execute(new RedisCallback<String>() {
                public String doInRedis(RedisConnection connection)
                        throws DataAccessException {
                    connection.flushDb();
                    return "success";
                }
            });
        }
        /**
         * 查看redis里有多少数据
         */
        public long dbSize() {
            return redisTemplate.execute(new RedisCallback<Long>() {
                public Long doInRedis(RedisConnection connection)
                        throws DataAccessException {
                    return connection.dbSize();
                }
            });
        }
        /**
         * 检查是否连接成功
         *
         * @return
         */
        public String ping() {
            return redisTemplate.execute(new RedisCallback<String>() {
                public String doInRedis(RedisConnection connection)
                        throws DataAccessException {
                    return connection.ping();
                }
            });
        }
        /**
         * 设置key的生命周期
         *
         * @param key
         * @param seconds
         *            单位(秒)
         * @return
         */
        public boolean expire(final String key, final long seconds) {
            return redisTemplate.execute(new RedisCallback<Boolean>() {
                public Boolean doInRedis(RedisConnection connection)
                        throws DataAccessException {
                    return connection.expire(key.getBytes(), seconds);
                }
            });
        }
        /**
         * 自增长
         *
         * @param key
         * @param length 增长步长
         * @return
         */
        public long incr (final String key){
            return redisTemplate.execute(new RedisCallback<Long>() {
                public Long doInRedis(RedisConnection connection)
                        throws DataAccessException {
                    return connection.incr(key.getBytes());
                }
                 
            });
        }
        /**
         * 自增长
         *
         * @param key
         * @param length 增长步长
         * @return
         */
        public long incrBy (final String key, final long len){
            return redisTemplate.execute(new RedisCallback<Long>() {
                public Long doInRedis(RedisConnection connection)
                        throws DataAccessException {
                    return connection.incrBy(key.getBytes(), len);
                }
            });
             
        }
        /**
         * 自增长
         *
         * @param key
         * @param length 增长步长
         * @return
         */
        public double incrBy (final String key, final double len){
            return redisTemplate.execute(new RedisCallback<Double>() {
                public Double doInRedis(RedisConnection connection)
                        throws DataAccessException {
                    return connection.incrBy(key.getBytes(), len);
                }
            });
        }
         
        public long eval(final String luaCommand) {
            return redisTemplate.execute(new RedisCallback<Long>() {
                public Long doInRedis(RedisConnection connection) throws DataAccessException {
                    return connection.eval(luaCommand.getBytes(), null,0);
                }
            });
        }
     
    }

      

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    package com.eshore.ismp.cache.processor;
     
    import org.apache.log4j.Logger;
    import org.springframework.beans.factory.annotation.Autowired;
    import org.springframework.stereotype.Service;
    import org.springframework.util.StringUtils;
     
    import com.alibaba.fastjson.JSON;
    import com.alibaba.fastjson.JSONObject;
    import com.eshore.ismp.cache.redis.RedisService;
    import com.eshore.ismp.common.entity.ResultInfo;
     
    /**
     *
     * //DESC: 管理门户缓存接口
     * @author zzx
     * @date 2016年5月20日 上午11:50:25
     */
    @Service
    public class AdminWebProcessor {
        private static final Logger logger = Logger.getLogger(AdminWebProcessor.class);
        private static final String ADMINWEB_USER = "ADMINWEB_USER_";
        private static final Long LIVETIME = 60*30L;
        @Autowired
        RedisService redisService;
         
        public String put(JSONObject param){
            Long userId = param.getLong("user_id");
            String userInfo = param.getString("user_info");
            ResultInfo  rs = new ResultInfo();
            if(userId==null || StringUtils.isEmpty(userInfo)){
                logger.error("参数错误");
                rs.setResult_code(2501);
                rs.setResult_detail("参数错误");
                return JSON.toJSONString(rs);
            }
            String key = ADMINWEB_USER+userId;
            redisService.set(key , userInfo,LIVETIME);
            rs.setResult_code(0);
            rs.setResult_detail("success");
            return JSON.toJSONString(rs);
        }
         
        public String get(JSONObject param){
            Long userId = param.getLong("user_id");
            String key = ADMINWEB_USER+userId;
            ResultInfo  rs = new ResultInfo();
            String user = redisService.get(key);
            rs.setResult_code(0);
            rs.setResult_detail("success");
            rs.setResult_data(user);
            return JSON.toJSONString(rs);
        }
         
        public String delete(JSONObject param){
            Long userId = param.getLong("user_id");
            String key = ADMINWEB_USER+userId;
            ResultInfo  rs = new ResultInfo();
            long isDel = redisService.del(key);
            rs.setResult_code(0);
            rs.setResult_detail("success");
            return JSON.toJSONString(rs);
        }
     
    }

      

      

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  • 原文地址:https://www.cnblogs.com/shoshana-kong/p/14136527.html
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