1.1 EntrySet 遍历EntrySet 是早期 HashMap 遍历的主要方法，其实现代码如下：publicstaticvoidmain(Strin...
String key=entry.getKey();//得到键 String value=entry.getValue();//得到值 System.out.println(key+"="+value); } } } /*output: 杨过=小龙女 飞鹏=夕瑶 喜羊羊=美羊羊*/ Map集合的Lambda遍历 package com.an.a; import java.util.*; import java.util.function.BiConsumer; import java.util....
publicJSONObject(Map<String, Object>map) {if(map ==null) {thrownewIllegalArgumentException("map is null."); }else{this.map =map; } } 例子: publicclassmapTest1 {publicstaticvoidmain(String[] args) {//创建 map对象Map<String, Object> map =newHashMap<String, Object>();//添加元素到集合m...
package com.softsec.demo; import java.io.*; import java.util.*; public class demoMap implements Cloneable{ public static void main(String[] srag) { List list = new ArrayList(); list.add(100); list.add(200); HashMap old_map = new HashMap(); old_map.put("name", "蔡虚坤");//...
import java.util.HashMap; import java.util.Iterator; import java.util.Map.Entry; public class HashMapDemo { public static void main(String[] args) { HashMap<String, String> map = new HashMap<String, String>(); // 向集合中添加数据 ...
output.FileOutputFormat; public class RunJob { public static void main(String[] args) { //设置环境变量HADOOP_USER_NAME,其值是root System.setProperty("HADOOP_USER_NAME", "root"); //Configuration类包含了Hadoop的配置 Configuration config =new Configuration(); //设置fs.defaultFS config.set("fs....
2、java bean 下文所依赖的User如下 代码语言:java AI代码解释 importlombok.AllArgsConstructor;importlombok.Data;importlombok.NoArgsConstructor;/** * @author alanchan * */@Data@AllArgsConstructor@NoArgsConstructorpublicclassUser{privateintid;privateStringname;privateStringpwd;privateStringemail;privateintage;pri...
1、Map的特点和基本增删改查Map:映射 public class TestMap { public static void main(String[] args) { Map<String,String> map = new HashMap<>(); //增加 map.put("CN", "中国");…
import java.util.*; import java.io.*; public class Anagrams { public static void main(String[] args) { int minGroupSize = Integer.parseInt(args[1]); // Read words from file and put into a simulated multimap Map<String, List<String>> m = new HashMap<String, List<String>>(); try...
import org.apache.hadoop.mapreduce.lib.output.FileOutputFormat; public class SortIntegers { public static void main(String[] args) { try { Configuration conf = new Configuration(); Job job = Job.getInstance(conf, "sort integers job"); job.setJarByClass(SortIntegers.class); job.setMapperClass(...