java中HashMap的遍历方式

Map<String, Object> map = new HashMap<>();
map.put("aaa", 1111);
map.put("bbb", 2222);
map.put("ccc", 3333);
//-------------------------- 方式1 --------------------------
Set<String> keys1 = map.keySet();
Iterator<String> iterator1 = keys1.iterator();
while (iterator1.hasNext()) {
    String key1 = iterator1.next();
    System.out.println(key1+" : "+map.get(key1));
}
//-------------------------- 方式2 --------------------------
Set<String> keys2 = map.keySet();
for (String key2 : keys2) {
    System.out.println(key2+" : "+map.get(key2));
}
//-------------------------- 方式3 --------------------------
Set<Map.Entry<String, Object>> entries3 = map.entrySet();
Iterator<Map.Entry<String, Object>> iterator3 = entries3.iterator();
Map.Entry<String, Object> entry3 = null;
while (iterator3.hasNext()) {
    entry3 = iterator3.next();
    System.out.println(entry3.getKey()+" : "+entry3.getValue());
}
//-------------------------- 方式4 --------------------------
Set<Map.Entry<String, Object>> entries4 = map.entrySet();
for (Map.Entry<String, Object> entry4 : entries4) {
    System.out.println(entry4.getKey()+" : "+entry4.getValue());
}
//-------------------------- 方式5 --------------------------
map.forEach((key5, value5) -> {
    System.out.println(key5+" : "+value5);
});
//-------------------------- 方式6 --------------------------
map.entrySet().stream().forEach((entry6) -> {
    System.out.println(entry6.getKey()+" : "+entry6.getValue());
});
//-------------------------- 方式7 --------------------------
map.entrySet().parallelStream().forEach((entry7) -> {
    System.out.println(entry7.getKey()+" : "+entry7.getValue());
});