javaredis存储对象存储
① redis怎么存储list对象
方案一:直接使用List结构,List里面存储二进制的任务Bean信息,这样做查询全部任务很方便,查询单条任务速度较慢,并且删除和修改状态很麻烦;方案二:直接使用Hash结构,Hash的key存储任务ID,value存储二进制的Bean信息,这样做查询所有任务、查询单条任务以及删除任务都很快,但是修改状态也必须先取出数据再修改再插入!
② redis存储对象大小2m
Redis 存储字符串和对象
1 测试类
import redis.clients.RedisClinet;
import redis.clients.SerializeUtil;
import redis.clients.jedis.Jedis;
public class Test {
/**
* Administrator
* @param args
*/
public static void main(String[] args) {
// 操作单独的文本串
Jedis redis= new Jedis( "10.2.31.38", 6379);
redis.set( "key", "value");
System. out.println(redis.get( "key"));
System. out.println(redis.del( "key"));
// 操作实体类对象
Goods good= new Goods(); // 这个Goods实体我就不写了啊
good.setName( "洗衣机" );
good.setNum(400);
good.setPrice(19l);
redis.set( "good".getBytes(), SerializeUtil. serialize(good));
byte[] value = redis.get( "good".getBytes());
Object object = SerializeUtil. unserialize(value);
if(object!= null){
Goods goods=(Goods) object;
System. out.println(goods.getName());
System. out.println(goods.getNum());
System. out.println(goods.getPrice());
}
System. out.println(redis.del( "good".getBytes()));
// 操作实体类对象2(实际上和上面是一样的)
String key= "goods-key";
Goods g= new Goods();
g.setName( "电风扇--d" );
g.setNum(200);
String temp=RedisClinet. getInstance().set(g, key);
System. out.println(temp);
Object o=RedisClinet. getInstance().get(key);
if(o!= null)
{
Goods g1=(Goods)o;
System. out.println(g1.getName());
System. out.println(g1.getNum());
}
System. out.println(RedisClinet. getInstance().del(key));
}
}
2 RedisClinet 客户端类
package redis.clients;
import redis.clients.jedis.Jedis;
/**
*
* @author ajun
*
*/
public class RedisClinet {
private static final String ip= "10.2.31.38";
private static final int port=6379;
protected static RedisClinet redis = new RedisClinet ();
protected static Jedis jedis = new Jedis( ip, port);;
static {
}
protected RedisClinet(){
System. out.println( " init Redis ");
}
public static RedisClinet getInstance()
{
return redis;
}
/**set Object*/
public String set(Object object,String key)
{
return jedis.set(key.getBytes(), SerializeUtil.serialize(object));
}
/**get Object*/
public Object get(String key)
{
byte[] value = jedis.get(key.getBytes());
return SerializeUtil. unserialize(value);
}
/**delete a key**/
public boolean del(String key)
{
return jedis.del(key.getBytes())>0;
}
}
3 序列化工具类
/**
*
*/
package redis.clients;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
/**
* @author Administrator
*
*/
public class SerializeUtil {
public static byte[] serialize(Object object) {
ObjectOutputStream oos = null;
ByteArrayOutputStream baos = null;
try {
// 序列化
baos = new ByteArrayOutputStream();
oos = new ObjectOutputStream(baos);
oos.writeObject(object);
byte[] bytes = baos.toByteArray();
return bytes;
} catch (Exception e) {
}
return null;
}
public static Object unserialize( byte[] bytes) {
ByteArrayInputStream s = null;
try {
// 反序列化
s = new ByteArrayInputStream(bytes);
ObjectInputStream ois = new ObjectInputStream(s);
return ois.readObject();
} catch (Exception e) {
}
return null;
}
}
③ redis 存储自定义java对象有几种方式
1,继承Serializable接口,反序列化成byte数组
2,把JavaBean转成JSON字符串
④ redis怎么存储类对象
Redis是Key-Value型内存数据库,不能直接存储对象,如果实体对象可以序列化,可以将序列化后的内容存入一个Value中。