hashmap可以用null为键值
摘要:import java.util.HashMap;import java.util.Map;import java.util.TreeMap;public class TestMain { public static void main(String[] args) { // HashMap可以的键值可以是null, "". Map<String, String> strMap1 = new HashMap<String, String>(); strMap1.put(null, "1"); strMap1.put("&
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posted @ 2012-01-12 22:19