說明：此處的排序 是指：
1： 往集合中插入元素的順序與遍歷元素的順序的關系；
2： 往對象中插入元素否會根據元素的大小排序
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public class MapSortTest {
public static void main(String[] args) {
System.out.println("放入順序為：a:aaa c:ccc b:bbb d:ddd ");
System.out.println("HashMap 排序測試");
Map map =
new HashMap();
map.put("a", "aaa");
map.put("c", "ccc");
map.put("b", "bbb");
map.put("d", "ddd");
Iterator iterator = map.keySet().iterator();
while (iterator.hasNext()) {
Object key = iterator.next();
System.out.println("key:"+key+" value:" + map.get(key));
}
System.out.println("HashMap 進出無次序 ； key大小無次序 ");
System.out.println("***********************************************************");
System.out.println("Hashtable 排序測試");
Hashtable tab =
new Hashtable();
tab.put("a", "aaa");
tab.put("c", "ccc");
tab.put("b", "bbb");
tab.put("d", "ddd");
Iterator iterator_1 = tab.keySet().iterator();
while (iterator_1.hasNext()) {
Object key = iterator_1.next();
System.out.println("key :"+key+" value:"+ tab.get(key));
}
System.out.println("Hashtable 進出無次序 ； key大小無次序 ");
System.out.println("***********************************************************");
System.out.println("TreeMap 排序測試");
TreeMap tmp =
new TreeMap();
tmp.put("a", "aaa");
tmp.put("c", "ccc");
tmp.put("b", "bbb");
tmp.put("d", "ddd");
Iterator iterator_2 = tmp.keySet().iterator();
while (iterator_2.hasNext()) {
Object key = iterator_2.next();
System.out.println("key:"+key+" value:" + tmp.get(key));
}
System.out.println("TreeMap 進出無次序 ； key大小從小到大 ");
System.out.println("***********************************************************");
System.out.println("LinkedHashMap 排序測試");
LinkedHashMap linkedHashMap =
new LinkedHashMap();
linkedHashMap.put("a", "aaa");
linkedHashMap.put("c", "ccc");
linkedHashMap.put("b", "bbb");
linkedHashMap.put("d", "ddd");
Iterator iterator2 = linkedHashMap.keySet().iterator();
while (iterator2.hasNext()) {
Object key = iterator2.next();
System.out.println("key:"+key+" value:" + linkedHashMap.get(key));
}
System.out.println("LinkedHashMap 先進先出； key大小無次序 ");
System.out.println();
System.out.println("ArrayList 排序測試");
System.out.println("放入順序為：aaa ccc bbb ddd");
ArrayList arrayList=
new ArrayList();
arrayList.add("aaa");
arrayList.add("ccc");
arrayList.add("bbb");
arrayList.add("ddd");
System.out.println("ArrayList 先進先出；值大小無次序 ");
// Collections.sort(arrayList);
for(
int i=0;i<arrayList.size();i++){
System.out.println(arrayList.get(i));
}
System.out.println("***********************************************************");
}
}
運行結果：
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放入順序為：a:aaa c:ccc b:bbb d:ddd
HashMap 排序測試
key:d value:ddd
key:b value:bbb
key:c value:ccc
key:a value:aaa
HashMap 進出無次序 ； key大小無次序
***********************************************************
Hashtable 排序測試
key :b value:bbb
key :a value:aaa
key :d value:ddd
key :c value:ccc
Hashtable 進出無次序 ； key大小無次序
***********************************************************
TreeMap 排序測試
key:a value:aaa
key:b value:bbb
key:c value:ccc
key:d value:ddd
TreeMap 進出無次序 ； key大小從小到大
***********************************************************
LinkedHashMap 排序測試
key:a value:aaa
key:c value:ccc
key:b value:bbb
key:d value:ddd
LinkedHashMap 先進先出； key大小無次序
ArrayList 排序測試
放入順序為：aaa ccc bbb ddd
LinkedHashMap 先進先出；值大小無次序
aaa
ccc
bbb
ddd
***********************************************************