Updating a java map entry

Question

I m facing a problem that seems to have no straighforward solution   I m using java util Map  and I want to update the value in a Key-Value pair   Right now  I m doing it lik this   private Map lt String int gt  table   new HashMap lt String int gt     public void update String key  int val        if   table containsKey key    return      Entry lt String int gt  entry      for  entry   table entrySet               if  entry getKey   equals key                  entry setValue val               break                      So is there any method so that I can get the required Entry object without having to iterate through the entire Map  Or is there some way to update the entry s value in place  Some method in Map like setValue String key  int val    jrh

User · Answer

If key is present table put key  val  will just overwrite the value else it ll create a new entry  Poof  and you are done       you can get the value from a map by using key is table get key   That s about it

User · Answer

Use  table put key  val     to add a new key value pair or overwrite an existing key s value   From the Javadocs      V put K key  V value   Associates the specified value with the specified key in this map  optional operation   If the map previously contained a mapping for the key  the old value is replaced by the specified value   A map m is said to contain a mapping for a key k if and only if m containsKey k  would return true

User · Answer

You just use the method  public Object put Object key  Object value    if the key was already present in the Map then the previous value is returned

[java] Updating a java map entry

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