在Java(或Scala)中迭代HashMaps的HashMap

for (Map.Entry<Integer, String> entry : hashMap.entrySet()) {
    Integer key = entry.getKey();
    String value = entry.getValue();
    // 处理键值对
}

Iterator<Map.Entry<Integer, String>> iterator = hashMap.entrySet().iterator();
while (iterator.hasNext()) {
    Map.Entry<Integer, String> entry = iterator.next();
    Integer key = entry.getKey();
    String value = entry.getValue();
    // 处理键值对
}

hashMap.entrySet().stream().forEach(entry -> {
    Integer key = entry.getKey();
    String value = entry.getValue();
    // 处理键值对
});

for ((key, value) <- hashMap) {
    // 处理键值对
}

hashMap.map { case (key, value) =>
    // 处理键值对
}

hashMap.foreach { case (key, value) =>
    // 处理键值对
}