Map

来源：互联网发布：朗读爱好者软件编辑：程序博客网时间：2024/06/06 05:41
import java.util.HashMap;import java.util.Iterator;import java.util.Map;import java.util.Set;public class TraversalMap {    public static void main(String[] args) {        Map<String, String> map = new HashMap<String, String>();        map.put("username", "qq");        map.put("password", "123");        map.put("userID", "1");        map.put("email", "qq@qq.com");        forMap(map);        System.out.println("--------------");        iteratorMap(map);        System.out.println("--------------");        keySetMap(map);        System.out.println("--------------");        entrySetMap(map);    }//entrySet()    private static void entrySetMap(Map<String, String> map) {        Iterator it = map.entrySet().iterator();        // System.out.println(map.entrySet().size());        String key;        String value;        while (it.hasNext()) {            Map.Entry entry = (Map.Entry) it.next();            key = entry.getKey().toString();            value = entry.getValue().toString();            System.out.println(key + "====>" + value);        }    }//keySet()    private static void keySetMap(Map<String, String> map) {        Iterator it = map.keySet().iterator();        while (it.hasNext()) {            String key;            String value;            key = it.next().toString();            value = map.get(key);            System.out.println(key + "--" + value);        }    }//iterator    private static void iteratorMap(Map<String, String> map) {        Set set = map.entrySet();        Iterator i = set.iterator();        while (i.hasNext()) {            Map.Entry<String, String> entry = (Map.Entry<String, String>) i                    .next();            System.out.println(entry.getKey() + "==" + entry.getValue());        }    }//for    private static void forMap(Map<String, String> map) {        for (Map.Entry<String, String> entry : map.entrySet()) {            System.out.println(entry.getKey() + "--->" + entry.getValue());        }    }}
0 0