hashmap Archives - Page 4 of 5

How to update a value, given a key in a hashmap?

Suppose we have a HashMap<String, Integer> in Java. How do I update (increment) the integer-value of the string-key for each existence of the ...

April 25, 2022
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Iterate through a HashMap [duplicate]

This question already has answers here: How do I efficiently iterate over each entry in a Java Map? (46 answers) Closed 2 years ...

April 9, 2022
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What are the differences between a HashMap and a Hashtable in Java?

What are the differences between a HashMap and a Hashtable in Java? Which is more efficient for non-threaded applications? 3 35

April 9, 2022
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Exception in thread “main” java.lang.StackOverflowError

April 8, 2022
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Difference between HashSet and HashMap?

They are entirely different constructs. A HashMap is an implementation of Map. A Map maps keys to values. The key look up occurs using the hash. On the ...

April 8, 2022
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Iterate through a HashMap [duplicate]

Iterate through the entrySet() like so: public static void printMap(Map mp) { Iterator it = mp.entrySet().iterator(); while (it.hasNext()) { Map.Entry pair = (Map.Entry)it.next(); System.out.println(pair.getKey() + ...

April 8, 2022
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What is the significance of load factor in HashMap?

The documentation explains it pretty well: An instance of HashMap has two parameters that affect its performance: initial capacity and load factor. The capacity is ...

April 7, 2022
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How to update a value, given a key in a hashmap?

map.put(key, map.get(key) + 1); should be fine. It will update the value for the existing mapping. Note that this uses auto-boxing. With the ...

April 7, 2022
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Collision resolution in Java HashMap

When you insert the pair (10, 17) and then (10, 20), there is technically no collision involved. You are just replacing the old value with the ...

April 7, 2022
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Java Hashmap: How to get key from value?

April 7, 2022
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