Java: how to convert HashMap<String, Object> to array
I need to convert a HashMap<String, Object> to an array; could anyone show me how it's done?
hashMap.keySet().toArray(); // returns an array of keys
hashMap.values().toArray(); // returns an array of values
Edit
Should be noted that the ordering of both arrays may not be the same, See oxbow_lakes answer for a better approach for iteration when the pair key/values are needed.
If you want the keys and values, you can always do this via the entrySet :
hashMap.entrySet().toArray(); // returns a Map.Entry<K,V>[]
From each entry you can (of course) get both the key and value via the getKey and getValue methods
If you have HashMap<String, SomeObject> hashMap then
hashMap.values().toArray();
will return an Object[]. If instead you want an array of the type SomeObject, you could use:
hashMap.values().toArray(new SomeObject[0]);
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