Map<String,String> m = System.getenv(); Set<Map.Entry<String,String>> s = m.entrySet(); Iterator it = s.iterator(); while (it.hasNext()) { Map.Entry e = (Map.Entry)it.next(); System.out.println(e.getKey()+":"+e.getValue()); }
晕,没完题就回答了,不好意思 Set<Map.Entry<String,ArrayList>> s = m.entrySet(); Iterator it = s.iterator(); while (it.hasNext()) { Map.Entry e = (Map.Entry)it.next(); System.out.println(e.getKey()); ArrayList list = e.getValue(); for (int i = 0;i<list.size();i++) { System.out.println(list.get(i)); } }
Set<String> keys = map.keySet();
Iterator<String> iterator = keys.iterator();
while(iterator.hasNext()) {
String key = iterator.next();
ArrayList arrayList = map.get(key);
for(Object o : arrayList) {
...
}
}
for(int i=0;i<10;i++){
ArrayList<String> lists=new ArrayList<String>();
for(int j=0;j<5;j++)
lists.add(j+"");
map.put(i+"", lists);
}
for(int i=0;i<map.size();i++){
ArrayList<String> lists=(ArrayList<String>)map.get(i+"");
for(int j=0;j<lists.size();j++)
System.out.print(lists.get(j));
}
map.put(...);for(Map.Entry<String, List<String>> entry : map.entrySet()) {
String key = entry.getKey();
List<String> values = entry.getValue();
for(String value : values) {
System.out.println(key + " --> " + value);
}
}
Set<Map.Entry<String,String>> s = m.entrySet();
Iterator it = s.iterator();
while (it.hasNext())
{
Map.Entry e = (Map.Entry)it.next();
System.out.println(e.getKey()+":"+e.getValue());
}
Set<Map.Entry<String,ArrayList>> s = m.entrySet();
Iterator it = s.iterator();
while (it.hasNext())
{
Map.Entry e = (Map.Entry)it.next();
System.out.println(e.getKey());
ArrayList list = e.getValue(); for (int i = 0;i<list.size();i++) {
System.out.println(list.get(i));
}
}