java hashmap foreach lambda code example

Example 1: loop in java 8

List<Integer> data = new ArrayList<>();

//Indexed Loop
for(int i = 0,size=data.size();i<size;i++){
	System.out.println(data.get(i));  
}

//For each loop
for(Integer element : data){
	System.out.println(element);
}

//Using forEach
data.forEach(System.out::println);

//Using Stream
data.stream().forEach(System.out::println)
  
//While loop
int i = 0;
while(i<data.size()){
	System.out.println(data.get(i++));  
}

Example 2: java 8 map foreach

public void iterateUsingStreamAPI(Map<String, Integer> map) {
    map.entrySet().stream()
      // ...
      .forEach(e -> System.out.println(e.getKey() + ":" + e.getValue()));
}