package cn.byhieg.collectiontutorial.maptutorial; import java.util.Iterator; import java.util.Map; import java.util.SortedMap; import java.util.TreeMap; /** * Created by shiqifeng on 2017/2/24. * Mail [email protected] */ public class TreeMapExample { public TreeMap<String,String> insertMap(){ TreeMap<String, String> maps = new TreeMap<>(); for (int i = 0 ; i < 10;i++) { maps.put(i + "", 10 * i + ""); } return maps; } public void getSmallestEntry(TreeMap<String, String> maps){ Map.Entry<String,String> entry = maps.firstEntry(); System.out.println("最小的Entry如下"); System.out.print("key = " + entry.getKey()); System.out.println(" value = " + entry.getValue()); } public void getLargestEntry(TreeMap<String,String> maps){ Map.Entry<String,String> entry = maps.lastEntry(); System.out.println("最大的Entry如下"); System.out.print("key = " + entry.getKey()); System.out.println(" value = " + entry.getValue()); } public void getHigherEntry(TreeMap<String,String> maps,String key){ Map.Entry<String,String> entry = maps.higherEntry(key); System.out.println("后一个的Entry如下"); System.out.print("key = " + entry.getKey()); System.out.println(" value = " + entry.getValue()); } public void getLowestEntry(TreeMap<String, String> maps, String key) { Map.Entry<String,String> entry = maps.lowerEntry(key); System.out.println("前一个的Entry如下"); System.out.print("key = " + entry.getKey()); System.out.println(" value = " + entry.getValue()); } public void getRangeMap(TreeMap<String, String> maps, String firstKey, String lastKey) { SortedMap<String,String> subMaps = maps.subMap(firstKey, lastKey); Iterator iterator = subMaps.entrySet().iterator(); System.out.println("子Map如下"); while (iterator.hasNext()) { Map.Entry<String, String> entry = (Map.Entry<String, String>) iterator.next(); System.out.print("key = " + entry.getKey()); System.out.println(" value = " + entry.getValue()); } } public void getHeadMap(TreeMap<String, String> maps, String firstKey,boolean isInclusive) { SortedMap<String,String> subMaps = maps.headMap(firstKey, isInclusive); Iterator iterator = subMaps.entrySet().iterator(); System.out.println(firstKey + "以前" + "所有的Map如下"); while (iterator.hasNext()) { Map.Entry<String, String> entry = (Map.Entry<String, String>) iterator.next(); System.out.print("key = " + entry.getKey()); System.out.println(" value = " + entry.getValue()); } } public void getTailMap(TreeMap<String, String> maps, String firstKey,boolean isInclusive) { SortedMap<String,String> subMaps = maps.headMap(firstKey, isInclusive); Iterator iterator = subMaps.entrySet().iterator(); System.out.println(firstKey + "以后" + "所有的Map如下"); while (iterator.hasNext()) { Map.Entry<String, String> entry = (Map.Entry<String, String>) iterator.next(); System.out.print("key = " + entry.getKey()); System.out.println(" value = " + entry.getValue()); } } }