HashMap is a collection to store (key,value) pairs and According to the documentation of HashMap the keys are always unique . If you add a key which already exists(collision) in the hashmap, the old value will be replaced.
Read moreIs there a limit to HashMap in Java?
HashMap is not limited , provided to have a load factor is increased. … And the largest number of elements you can have before the HashMap will try to double its size to 2^31 (which it cannot do) is ( 2^30 * loadFactor ) or about 700 million for the default load factor.
Read moreWhat is the problem with HashMap in Java?
HashMap’s methods are not synchronized . HashTable is more or less obsolete and people writing new code should avoid using a HashTable. In a HashMap, keys are always unique. i.e., there cannot be 2 entries with the same key.
Read moreHow do you make a HashMap key immutable?
Make HashMap key object immutable Also, this class must honor the hashCode() and equals() methods contract . This is the main reason why immutable classes like String , Integer or other wrapper classes are a good key object candidate.
Read moreIs map containsKey case sensitive?
Show activity on this post. Closed 6 years ago. I want to know whether a particular key is present in a HashMap, so i am using containsKey(key) method. But it is case sensitive ie it does not returns true if there is a key with Name and i am searching for name.
Read moreIs HashMap keys case sensitive?
You know keys in the java. util. HashMap are case sensitive . It means you can keep both “abc” and “ABC” as keys in the same map.
Read more