41 lines
955 B
Java
41 lines
955 B
Java
package jTest;
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import java.util.SortedMap;
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import java.util.TreeMap;
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public class TreeMapTest {
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public static void main(String[] args) {
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TreeMap<String, Object> treeMap = new TreeMap<>() {{
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put("c", 3);
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put("a", 1);
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put("b", 2);
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put("e", 5);
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put("d", 4);
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}};
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// 会自动排序
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System.out.println(treeMap);
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// 遍历集合
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treeMap.forEach((key, value) -> {
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System.out.println("key：" + key);
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System.out.println("value：" + value);
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});
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SortedMap<String, Object> sortedMap = new TreeMap<>() {{
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put("c", 3);
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put("a", 1);
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put("b", 2);
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put("e", 5);
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put("d", 4);
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}};
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// 拿到第一个值
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System.out.println(sortedMap.firstKey());
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// 最后一个值
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System.out.println(sortedMap.lastKey());
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}
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}
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