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adding objects to HashMap that have duplicate keys

Rachel Glenn
Ranch Hand

Joined: Oct 24, 2012
Posts: 95
If I have a HashMap, and I call .put() several times with the same key..for example..



Then the first put() call will return true and the second put() call will return false because the "Monday" key already exists?
Jayesh A Lalwani
Bartender

Joined: Jan 17, 2008
Posts: 2347
    
  28

put doesn't return a boolean. put returns the previous value. So, first call will return null and second call will return the first object
 
It is sorta covered in the JavaRanch Style Guide.
 
subject: adding objects to HashMap that have duplicate keys