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);
    }
 
}

  

  

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