Redistemplate common collection instructions opsforvalue (II)

​ The basic configuration has been introduced in the previous 《RedisTemplate Instructions for common sets ( One )》 Has been introduced in , Now let's introduce it directly opsForValue() Use of methods ：

1、set(K key, V value)

​ Add a value of string type ,key It's a key ,value Is the value .

redisTemplate.opsForValue().set("stringValue","bbb");

2、get(Object key)

obtain key The value of the key .

String stringValue = redisTemplate.opsForValue().get("stringValue")+"";
System.out.println(" adopt get(Object key) Method to get set(K key, V value) Method to add a new string value :" + stringValue);

3、append(K key, String value)

Add a new string to the end based on the original value .

redisTemplate.opsForValue().append("stringValue","aaa");
String stringValueAppend = redisTemplate.opsForValue().get("stringValue")+"";
System.out.println(" adopt append(K key, String value) Method to modify the string :"+stringValueAppend);

4、get(K key, long start, long end)

Intercept key The key corresponds to the value string , From the start subscript position to the end subscript position ( Include end subscript ) String .

String cutString = redisTemplate.opsForValue().get("stringValue",0,3);
System.out.println(" adopt get(K key, long start, long end) Method to get the intercepted string :"+cutString);

5、getAndSet(K key, V value)

Get the original key Key and assign a new value .

String oldAndNewStringValue = redisTemplate.opsForValue().getAndSet("stringValue","ccc")+"";
System.out.print(" adopt getAndSet(K key, V value) Method to get the original " + oldAndNewStringValue + ",");
String newStringValue = redisTemplate.opsForValue().get("stringValue")+"";
System.out.println(" Modified value :"+newStringValue);

6、setBit(K key, long offset, boolean value)

key The value of the key value Corresponding ascii code , stay offset The location of ( Count from left to right ) Turn into value.

redisTemplate.opsForValue().setBit("stringValue",1,false);
newStringValue = redisTemplate.opsForValue().get("stringValue")+"";
System.out.println(" adopt setBit(K key,long offset,boolean value) Method modified value :"+newStringValue);

7、getBit(K key, long offset)

Determine the specified location ASCII The code bit Whether a is 1.

boolean bitBoolean = redisTemplate.opsForValue().getBit("stringValue",1);
System.out.println(" adopt getBit(K key,long offset) Method judgment assignment bit The value of bits is :" + bitBoolean);

8、size(K key)

Gets the length of the specified string .

Long stringValueLength = redisTemplate.opsForValue().size("stringValue");
System.out.println(" adopt size(K key) Method to get the length of the string :"+stringValueLength);

9、increment(K key, double delta)

Incrementally move double Values are stored in variables .

double stringValueDouble = redisTemplate.opsForValue().increment("doubleValue",5); 
System.out.println(" adopt increment(K key, double delta) Method to store... Incrementally double value :" + stringValueDouble);

10、increment(K key, long delta)

Incrementally move long Values are stored in variables .

double stringValueLong = redisTemplate.opsForValue().increment("longValue",6); 
System.out.println(" adopt increment(K key, long delta) Method to store... Incrementally long value :" + stringValueLong);

11、setIfAbsent(K key, V value)

If the key does not exist, add it , Being does not change the value that is already there .

boolean absentBoolean = redisTemplate.opsForValue().setIfAbsent("absentValue","fff");
System.out.println(" adopt setIfAbsent(K key, V value) Method to determine the value of the variable absentValue Whether there is :" + absentBoolean);
if(absentBoolean){ 
    
    String absentValue = redisTemplate.opsForValue().get("absentValue")+"";
    System.out.print(", non-existent , Then the new value is :"+absentValue);
    boolean existBoolean = redisTemplate.opsForValue().setIfAbsent("absentValue","eee");
    System.out.print(", Call again setIfAbsent(K key, V value) Judge absentValue Whether it exists and reassigns :" + existBoolean);
    if(!existBoolean){ 
    
        absentValue = redisTemplate.opsForValue().get("absentValue")+"";
        System.out.print(" If there is , After re assignment absentValue The value of the variable is :" + absentValue);
    }
}

12、set(K key, V value, long timeout, TimeUnit unit)

​ Set the expiration time of the variable value .

redisTemplate.opsForValue().set("timeOutValue","timeOut",5,TimeUnit.SECONDS);
String timeOutValue = redisTemplate.opsForValue().get("timeOutValue")+"";
System.out.println(" adopt set(K key, V value, long timeout, TimeUnit unit) Method to set the expiration time , Data obtained before expiration :"+timeOutValue);
Thread.sleep(5*1000);
timeOutValue = redisTemplate.opsForValue().get("timeOutValue")+"";
System.out.print(", wait for 10s later , Get the value of :"+timeOutValue);

13、set(K key, V value, long offset)

Overwrite the value starting from the specified position .

redisTemplate.opsForValue().set("absentValue","dd",1);
String overrideString = redisTemplate.opsForValue().get("absentValue")+"";
System.out.println(" adopt set(K key, V value, long offset) Method covers the value of the part :"+overrideString);

14、multiSet(Map<? extends K,? extends V> map)

Set up map Assemble to redis.

Map valueMap = new HashMap();
valueMap.put("valueMap1","map1");
valueMap.put("valueMap2","map2");
valueMap.put("valueMap3","map3");
redisTemplate.opsForValue().multiSet(valueMap);

15、multiGet(Collection keys)

Take out the corresponding... According to the set value value .

// according to List Set to get the corresponding value value 
List paraList = new ArrayList();
paraList.add("valueMap1");
paraList.add("valueMap2");
paraList.add("valueMap3");
List<String> valueList = redisTemplate.opsForValue().multiGet(paraList);
for (String value : valueList){ 
    
    System.out.println(" adopt multiGet(Collection<K> keys) Method to get map value :" + value);
}

16、multiSetIfAbsent(Map<? extends K,? extends V> map)

If the corresponding map Collection name does not exist , Then add , If it exists, it will not be modified .

Map valueMap = new HashMap();
valueMap.put("valueMap1","map1");
valueMap.put("valueMap2","map2");
valueMap.put("valueMap3","map3");
redisTemplate.opsForValue().multiSetIfAbsent(valueMap);

This is the end of the introduction opsForValue() Use of methods , The specific code will be given in the last article .