1.å
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public class TestMap {
public static Map<Integer, Integer> map = new HashMap<Integer, Integer>();
}
2.keySet values
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// KeySet è·åkey
public void testKeySet() {
for (Integer key : map.keySet()) {
System.out.println(key);
}
}
// values è·åvalue
public void testValues() {
for (Integer value : map.values()) {
System.out.println(value);
}
}
3.keySet get(key)
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// keySet get(key) è·åkey and value
public void testKeySetAndGetKey() {
for (Integer key : map.keySet()) {
System.out.println(key + ":" + map.get(key));
}
}
4.entrySet
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// entrySet è·åkey and value
public void testEntry() {
for (Map.Entry<Integer, Integer> entry : map.entrySet()) {
System.out.println(entry.getKey() + ":" + entry.getValue());
}
}
5.Iterator
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ä½Iteratorä¹æå
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// Iterator entrySet è·åkey and value
public void testIterator() {
Iterator<Map.Entry<Integer, Integer>> it = map.entrySet().iterator();
while (it.hasNext()) {
Map.Entry<Integer, Integer> entry = it.next();
System.out.println(entry.getKey() + ":" + entry.getValue());
// it.remove(); å é¤å
ç´
}
}
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