Iterate over a Hashmap

HashMap:

If you just want to iterate over the values, use

for (Object value : map.values()) { // ... }

if you just want to iterate over keys:

for (String key : map.keySet()) {
    // ...
}

Finally, if you want both the key and value, use entrySet():

for (Map.Entry<String, Object> entry : map.entrySet()) {
    String key = entry.getKey();
    Object value = entry.getValue();
    // ...
}

One caveat: if you want to remove items mid-iteration, you’ll need to do so via an Iterator (see karim79’s answer). However, changing item values is OK (see Map.Entry).

ddd

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