时间解决Java中Redis数据过期时间问题（redisjava过期）

Time Solving Redis Data Expiration Time Issue in Java

Redis is a common non-relational database used in Java software development. It’s an open source, networked, in-memory, key-value data store, a great choice for caching or small jobs that need to be done quickly, like setting or omitting data in the form of string, hash, list, set, or sorted set.

Redis is often used to store volatile data which expire automatically after some time. By default, if no time is specified, the data stays in the system forever and never expires. Long-term data stored in redis usually needs to expire. In this case, data in redis needs to expire after a certain amount of time and be exposed to the Java application performing a data request.

The way to solve the problem of data expiry in Redis is to use the EXPIRE command. It takes two parameters, the first one being the key of the item we wished to set an expiry time for, the second parameter being an expiration time in seconds.

For example, if we wish to set a key-value pair “username” as “sakura1314” for 60 seconds,the command to be used is

set username “sakura1314” 
expire username  60 

This command will set the key “username” with the value of “sakura1314”, the item will expire after 60 seconds.

When expiration is used in Java applications, it is often desirable to set the expiration time to a time when the application de facto ends. Java provides an API to retrieve the end time of an application.

For example:

import java.io.IOException;
import java.util.concurrent.TimeUnit;

public class App {
    public static void main(String[] args) throws IOException {
        long endTime = System.currentTimeMillis() + TimeUnit.MINUTE.toMillis(3);
    }
}

This returns the expiration time in milliseconds since the beginning of the Unix era (01/01/1970). This can conveniently be used to set the expiration time using the Redis -expire command.

In conclusion, the expiration time for the data in Redis can be adjusted by setting the expiration time with the Redis -expire command. Additionally, Java provides an easy way to retrieve the end time for an application, allowing for an easy implementation of an expiration time for data requests.