4种遍历map的方法。
通过map.keySet遍历
Map<String,String> map = new HashMap<String,String>();
map.put("key1", "value1");
map.put("key2", "value2");
map.put("key3", "value3");
for(String key : map.keySet()) {
String value = map.get(key);
System.out.println(value);
}
通过map.entrySet遍历
Map<String, String> map = new HashMap<String, String>();
map.put("key1", "value1");
map.put("key2", "value2");
map.put("key3", "value3");
for (Map.Entry<String, String> entry : map.entrySet()) {
String key = entry.getKey();
String value = entry.getValue();
System.out.println(value);
}
通过map.values()
Map<String, String> map = new HashMap<String, String>();
map.put("key1", "value1");
map.put("key2", "value2");
map.put("key3", "value3");
for (String v : map.values()) {
String value = v;
System.out.println(value);
}
通过Map.entrySet迭代器
只和第二种遍历Map.entrySet的方式不同
Map<String, String> map = new HashMap<String, String>();
map.put("key1", "value1");
map.put("key2", "value2");
map.put("key3", "value3");
Iterator<Map.Entry<String, String>> it = map.entrySet().iterator();
while (it.hasNext()) {
String value = it.next().getValue();
System.out.println(value);
}