对?set?的遍历
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class="java">//1.迭代遍历: Set<String> set = new HashSet<String>(); Iterator<String> it = set.iterator(); while (it.hasNext()) { String str = it.next(); System.out.println(str); } //2.for循环遍历: for (String str : set) { System.out.println(str); } //优点还体现在泛型 假如 set中存放的是Object Set<Object> set = new HashSet<Object>(); //for循环遍历: for (Object obj: set) { if(obj instanceof Integer){ int aa= (Integer)obj; }else if(obj instanceof String){ String aa = (String)obj } ........ }
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