java 去英文单词出现的次数

Love The Way You Lie 2022-06-17 12:15 162阅读 0赞

代码如下所示：

package test3;
    /**
     * 去英文单词出现的次数
     * @author saicy (博客http://blog.csdn.net/sai739295732/)
     */
    import java.util.Comparator;
    import java.util.LinkedHashMap;
    import java.util.Map;
    import java.util.Map.Entry;
    import java.util.Scanner;
    import java.util.TreeSet;
    import java.util.regex.Matcher;
    import java.util.regex.Pattern;
    
    
    public class Main{
        private static Scanner scan;
    	public static void main(String[] args){
            scan = new Scanner(System.in);
            String  str=scan.nextLine();
            Main m = new Main();
            m.getValue(str);
        }
        public void getValue(String str){
        	//提取出单词
        	Map<String,Integer> map = getString(str,"[a-zA-Z0-9]+");
        	//排序
        	TreeSet<Entry<String, Integer>> set = sortMap(map);
        	//输出数据
        	for(Entry<String, Integer> entry:set){
        		System.out.println(entry.getKey()+" "+entry.getValue());
        	}
        }
        private TreeSet<Entry<String, Integer>> sortMap(Map<String, Integer> map) {
        	TreeSet<Entry<String, Integer>> set = new TreeSet<Entry<String, Integer>>(new Comparator<Entry<String, Integer>>() {
    			@Override
    			public int compare(Entry<String, Integer> o1, Entry<String, Integer> o2) {
    				int count1 = o1.getValue().intValue();
    				int count2 = o2.getValue().intValue();
    				//比较次数
    				if(count1>count2){
    					return -1;
    				}else if(count1<count2){
    					return 1;
    				}else{
    					//比较手写字母的大小
    					int key1 = (int)o1.getKey().charAt(0);
    					int key2 = (int)o2.getKey().charAt(0);
    					if(key1>key2){
    						return 1;
    					}else if(key1<key2){
    						return -1;
    					}else{
    						return 0;
    					}
    				}
    			}
    		});
        	set.addAll(map.entrySet());
    		return set;
    	}
    	private Map<String,Integer> getString(String str, String regx) {  
        	Map<String,Integer> map = new LinkedHashMap<>();
            //1.将正在表达式封装成对象Patten 类来实现  
            Pattern pattern = Pattern.compile(regx);  
            //2.将字符串和正则表达式相关联  
            Matcher matcher = pattern.matcher(str);  
            //3.String 对象中的matches 方法就是通过这个Matcher和pattern来实现的。  
            //System.out.println(matcher.matches());  
            //查找符合规则的子串  
            while(matcher.find()){  
                //获取 字符串  
                //将截取的英文单词转为小写
                String mapKey = matcher.group().toLowerCase();
                Integer count = map.get(mapKey);
                //存储英文单词出现的次数
                if(count!=null){
                	map.put(mapKey,count.intValue()+1);
                }else{
                	map.put(mapKey,new Integer(1));
                }
            }
            return map;
        }  
        
    }

输出结果：

![Center][]

[Center]: /images/20220617/480dc3a4078a40a6859df2bb7ebf7c82.png