Redis存储List对象

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Redis 存储List对象
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分类： NoSQL 2012-06-11 16:33243人阅读评论(0)收藏举报



       如果需要用到Redis存储List对象，而list又不需要进行操作，可以按照MC的方式进行存储，不过Jedis之类的客户端没有提供API，可以有两种思路实现：

1.      分别序列化 elements ,然后 set 存储

2.    序列化List对象，set存储

这两种方法都类似MC的 Object方法存储，运用这种方式意味着放弃Redis对List提供的操作方法。




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01.import net.spy.memcached.compat.CloseUtil; 
02.import net.spy.memcached.compat.log.Logger; 
03.import net.spy.memcached.compat.log.LoggerFactory; 
04.import redis.clients.jedis.Client; 
05.import redis.clients.jedis.Jedis; 
06.import redis.clients.jedis.JedisPool; 
07.import redis.clients.jedis.JedisPoolConfig; 
08. 
09.import java.io.*; 
10.import java.util.ArrayList; 
11.import java.util.List; 
12.import java.util.Random; 
13. 
14./**
15. * Created by IntelliJ IDEA.
16. * User: lifeng.xu
17. * Date: 12-6-11
18. * Time: 上午11:10
19. * To change this template use File | Settings | File Templates.
20. */ 
21.public class JedisTest { 
22. 
23.    private static Logger logger = LoggerFactory.getLogger(JedisTest.class); 
24. 
25.    /**
26.     * Jedis Pool for Jedis Resource
27.     * @return
28.     */ 
29.    public static JedisPool buildJedisPool(){ 
30.        JedisPoolConfig config = new JedisPoolConfig(); 
31.        config.setMaxActive(1); 
32.        config.setMinIdle(50); 
33.        config.setMaxIdle(3000); 
34.        config.setMaxWait(5000); 
35.        JedisPool jedisPool = new JedisPool(config, 
36.                "*****", ****); 
37.        return jedisPool; 
38.    } 
39. 
40.    /**
41.     * Test Data
42.     * @return
43.     */ 
44.    public static List<User> buildTestData(){ 
45.        User a = new User(); 
46.        a.setName("a"); 
47.        User b = new User(); 
48.        b.setName("b"); 
49.        List<User> list = new ArrayList<User>(); 
50.        list.add(a); 
51.        list.add(b); 
52.        return list; 
53.    } 
54. 
55.    /**
56.     * Test for
57.     */ 
58.    public static void testSetElements(){ 
59.        List<User> testData = buildTestData(); 
60.        Jedis jedis = buildJedisPool().getResource(); 
61.        String key = "testSetElements" + new Random(1000).nextInt(); 
62.        jedis.set(key.getBytes(), ObjectsTranscoder.serialize(testData)); 
63. 
64.        //验证 
65.        byte[] in = jedis.get(key.getBytes()); 
66.        List<User> list = ObjectsTranscoder.deserialize(in); 
67.        for(User user : list){ 
68.            System.out.println("testSetElements user name is:" + user.getName()); 
69.        } 
70.    } 
71. 
72.    public static void testSetEnsemble(){ 
73.        List<User> testData = buildTestData(); 
74.        Jedis jedis = buildJedisPool().getResource(); 
75.        String key = "testSetEnsemble" + new Random(1000).nextInt(); 
76.        jedis.set(key.getBytes(), ListTranscoder.serialize(testData)); 
77. 
78.        //验证 
79.        byte[] in = jedis.get(key.getBytes()); 
80.        List<User> list = (List<User>)ListTranscoder.deserialize(in); 
81.        for(User user : list){ 
82.            System.out.println("testSetEnsemble user name is:" + user.getName()); 
83.        } 
84.    } 
85. 
86.    public static void main(String[] args) { 
87.        testSetElements(); 
88.        testSetEnsemble(); 
89.    } 
90. 
91.    public static void close(Closeable closeable) { 
92.        if (closeable != null) { 
93.            try { 
94.                closeable.close(); 
95.            } catch (Exception e) { 
96.                logger.info("Unable to close %s", closeable, e); 
97.            } 
98.        } 
99.    } 
100. 
101.    static class User implements Serializable{ 
102.        String name; 
103. 
104.        public String getName() { 
105.            return name; 
106.        } 
107. 
108.        public void setName(String name) { 
109.            this.name = name; 
110.        } 
111.    } 
112. 
113.    static class ObjectsTranscoder{ 
114.         
115.        public static byte[] serialize(List<User> value) { 
116.            if (value == null) { 
117.                throw new NullPointerException("Can't serialize null"); 
118.            } 
119.            byte[] rv=null; 
120.            ByteArrayOutputStream bos = null; 
121.            ObjectOutputStream os = null; 
122.            try { 
123.                bos = new ByteArrayOutputStream(); 
124.                os = new ObjectOutputStream(bos); 
125.                for(User user : value){ 
126.                    os.writeObject(user); 
127.                } 
128.                os.writeObject(null); 
129.                os.close(); 
130.                bos.close(); 
131.                rv = bos.toByteArray(); 
132.            } catch (IOException e) { 
133.                throw new IllegalArgumentException("Non-serializable object", e); 
134.            } finally { 
135.                close(os); 
136.                close(bos); 
137.            } 
138.            return rv; 
139.        } 
140. 
141.        public static List<User> deserialize(byte[] in) { 
142.            List<User> list = new ArrayList<User>(); 
143.            ByteArrayInputStream bis = null; 
144.            ObjectInputStream is = null; 
145.            try { 
146.                if(in != null) { 
147.                    bis=new ByteArrayInputStream(in); 
148.                    is=new ObjectInputStream(bis); 
149.                    while (true) { 
150.                        User user = (User) is.readObject(); 
151.                        if(user == null){ 
152.                            break; 
153.                        }else{ 
154.                            list.add(user); 
155.                        } 
156.                    } 
157.                    is.close(); 
158.                    bis.close(); 
159.                } 
160.            } catch (IOException e) { 
161.                logger.warn("Caught IOException decoding %d bytes of data", 
162.                        in == null ? 0 : in.length, e); 
163.            } catch (ClassNotFoundException e) { 
164.                logger.warn("Caught CNFE decoding %d bytes of data", 
165.                        in == null ? 0 : in.length, e); 
166.            } finally { 
167.                CloseUtil.close(is); 
168.                CloseUtil.close(bis); 
169.            } 
170.            return list; 
171.        } 
172.    } 
173.     
174.    static class ListTranscoder{ 
175.        public static byte[] serialize(Object value) { 
176.            if (value == null) { 
177.                throw new NullPointerException("Can't serialize null"); 
178.            } 
179.            byte[] rv=null; 
180.            ByteArrayOutputStream bos = null; 
181.            ObjectOutputStream os = null; 
182.            try { 
183.                bos = new ByteArrayOutputStream(); 
184.                os = new ObjectOutputStream(bos); 
185.                os.writeObject(value); 
186.                os.close(); 
187.                bos.close(); 
188.                rv = bos.toByteArray(); 
189.            } catch (IOException e) { 
190.                throw new IllegalArgumentException("Non-serializable object", e); 
191.            } finally { 
192.                close(os); 
193.                close(bos); 
194.            } 
195.            return rv; 
196.        } 
197. 
198.        public static Object deserialize(byte[] in) { 
199.            Object rv=null; 
200.            ByteArrayInputStream bis = null; 
201.            ObjectInputStream is = null; 
202.            try { 
203.                if(in != null) { 
204.                    bis=new ByteArrayInputStream(in); 
205.                    is=new ObjectInputStream(bis); 
206.                    rv=is.readObject(); 
207.                    is.close(); 
208.                    bis.close(); 
209.                } 
210.            } catch (IOException e) { 
211.                logger.warn("Caught IOException decoding %d bytes of data", 
212.                        in == null ? 0 : in.length, e); 
213.            } catch (ClassNotFoundException e) { 
214.                logger.warn("Caught CNFE decoding %d bytes of data", 
215.                        in == null ? 0 : in.length, e); 
216.            } finally { 
217.                CloseUtil.close(is); 
218.                CloseUtil.close(bis); 
219.            } 
220.            return rv; 
221.        } 
222.    } 
223.} 



PS：Redsi中存储list没有封装对Object的API，是不是也是倾向于只存储用到的字段，而不是存储Object本身呢？Redis是一个In-Mem的产品，会觉得我们应用的方式。







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