hashmap iterator code example
Example 1: java map iteration
// 1. for-each with Entry
Map<Integer, Integer> map = new HashMap<Integer, Integer>();
for (Map.Entry<Integer, Integer> entry : map.entrySet()) {
System.out.println("Key = " + entry.getKey() + ", Value = " + entry.getValue());
}
// 2. for-each with key or value each (faster)
Map<Integer, Integer> map = new HashMap<Integer, Integer>();
//iterating over keys only
for (Integer key : map.keySet()) {
System.out.println("Key = " + key);
}
//iterating over values only
for (Integer value : map.values()) {
System.out.println("Value = " + value);
}
// 3. Using Iterator
Map<Integer, Integer> map = new HashMap<Integer, Integer>();
// With Generic
Iterator<Map.Entry<Integer, Integer>> entries = map.entrySet().iterator();
while (entries.hasNext()) {
Map.Entry<Integer, Integer> entry = entries.next();
System.out.println("Key = " + entry.getKey() + ", Value = " + entry.getValue());
}
// No Generic
Map map = new HashMap();
Iterator entries = map.entrySet().iterator();
while (entries.hasNext()) {
Map.Entry entry = (Map.Entry) entries.next();
Integer key = (Integer)entry.getKey();
Integer value = (Integer)entry.getValue();
System.out.println("Key = " + key + ", Value = " + value);
}
Example 2: java iterate through hashmap
for (Map.Entry<String, String> entry : yourHashMap.entrySet()) {
System.out.println(entry.getKey() + " = " + entry.getValue());
}
Example 3: how to iterate hashmap in java
for (Map.Entry<String, String> entry : yourHashMap.entrySet()) {
System.out.println(entry.getKey() + " = " + entry.getValue());
}
map.forEach((k, v) -> {
System.out.format("key: %s, value: %d%n", k, v);
});
Example 4: iterating over a hashmap
for(Map.Entry<String, Integer> entry : hashMap.entrySet()) {
String key = entry.getKey();
Integer value = entry.getValue();
//do something with the key and value
}
Example 5: how to iterate hashmap java
Map<Integer, Integer> map = new HashMap<Integer, Integer>();
for (Map.Entry<Integer, Integer> entry : map.entrySet()) {
System.out.println("Key = " + entry.getKey() + ", Value = " + entry.getValue());
}
Example 6: iterate hashmap java
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() + " = " + pair.getValue());
it.remove(); // avoids a ConcurrentModificationException
}
}