Java HashMapについては追加順に並べ替えが表示されていません

一般的にHashMapのアクセス順序は一致しません.たとえば、次のようになります.

@Test
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public void test(){
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    HashMapmap=new HashMap();
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    map.put("1", "111");
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    map.put("2", "122");
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    map.put("3", "133");
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    map.put("4", "144");
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    map.put("5", "155");
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    for(String str:map.keySet()){
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        System.out.println("key is "+str+" value is "+map.get(str));
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    }
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}

 出力の結果、key is 3 value is 133 key is 2 value is 122 key is 1 value is 111 key is 5 value is 155 key is 4 value is 144、つまりデータの取り出し順序が格納時と同じであることは保証されないが、LinkedHashMapはこれを行うことができる

LinkedHashMaplinkedHashMap=new LinkedHashMap();
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linkedHashMap.put("1", "111");
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linkedHashMap.put("2", "222");
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linkedHashMap.put("3", "333");
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linkedHashMap.put("4", "444");
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linkedHashMap.put("5", "555");
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for(String str:linkedHashMap.keySet()){
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    System.out.println("key is "+str+" value is "+linkedHashMap.get(str));
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}

出力結果:key is 1 value is 111 key is 2 value is 222 key is 3 value is 333 key is 4 value is 444 key is 5 value is 555
TreeMapもできます 

TreeMapmap=new TreeMap();
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map.put("1", "1111");
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map.put("2", "2222");
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map.put("3", "3333");
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map.put("4", "4444");
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map.put("5", "5555");
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for(String str:map.keySet()){
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    System.out.println("key is "+str+" value is "+map.get(str));
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}

出力結果key is 1 value is 1111 key is 2 value is 2222 key is 3 value is 3333 key is 4 value is 4444 key is 5 value is 5555