The INCR key of redis implements simple traffic statistics

• redis INCR document

  • File

• thinking

  • For example, use the incr of redis to write a method on the details page to make auto statistics on the visit.
  • Get all the key s of incr and display them in order
    • It should be noted here that keys cannot be used when taking all keys. Because redis is single threaded and traverses kye in a large amount, which may cause redis to block, we use scan

• Code

  • Deposit

        /**
        *  Redis Incr Self increment
        * @param serviceName
        * @param id
        */
        public void redisCount(String serviceName,String id){
            boolean flag = redisTemplate.hasKey(serviceName +":"+ id);
            //non-existent
            if (!flag){
                GenericToStringSerializer genericToStringSerializer = new GenericToStringSerializer(Object.class);
                redisTemplate.setValueSerializer(genericToStringSerializer);
                redisTemplate.opsForValue().set(serviceName +":"+ id, 1);
            } else {
                redisTemplate.opsForValue().increment(serviceName +":"+ id);
            }
    
        }
    

  The setValueSerializer here, because the value initialization sequence is String, needs to be serialized to store the value type

  • take

  	/**
  	 * Get all keys through the scan of redis
  	 * @param key
  	 * @return
  	 */
  	public void scan(String pattern, Consumer<byte[]> consumer) {
  		this.stringRedisTemplate.execute((RedisConnection connection) -> {
  			try (Cursor<byte[]> cursor = connection.scan(ScanOptions.scanOptions().count(Long.MAX_VALUE).match(pattern).build())) {
  				cursor.forEachRemaining(consumer);
  				return null;
  			} catch (IOException e) {
  				e.printStackTrace();
  				throw new RuntimeException(e);
  			}
  		});
  	}
  
  
  	/**
  	 * Get qualified key
  	 * @param pattern	expression
  	 * @return
  	 */
  	public List<String> keys(String pattern) {
  		List<String> keys = new ArrayList<>();
  		this.scan(pattern, item -> {
  			//Qualified key
  			String key = new String(item, StandardCharsets.UTF_8);
  			keys.add(key);
  		});
  		return keys;
  	}
  

  For the method and introduction of scan access, here you can refer to the information on the Internet. Data address