Java中各种数据类型之间的转换

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Integer i = Integer.parseInt();

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Integer a;
String str = Integer.toString(a);

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char a='9';
Integer i =(int)a - (int)('0');

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Integer i;
char c = (char)i;

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String str ="abc";
List<Character> list = new ArrayList<Character>();
for(int i=0;i<str.length();i++){
	list.add(str.charAt(i));
}

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String str ="";
List<Character> list = new ArrayList<Character>();
for(int i=0;i<list.size();i++){
	str += list.get(i);
}

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String[] s = new String[]{"A", "B", "C", "D","E"};
List<String> list = Arrays.asList(s);

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String[] dest = list.toArray(new String[0]);

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Set<String> set = new HashSet<>(list);

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List<String> list_1 = new ArrayList<>(set);

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s = new String[]{"A", "B", "C", "D","E"};
set = new HashSet<>(Arrays.asList(s));

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dest = set.toArray(new String[0]);