Java给出一串字符串，求每个字符出现的个数

布满荆棘的人生 2022-02-15 07:25 213阅读 0赞

方法一：

package ceshi;
    
    import java.util.HashMap;
    import java.util.Map;
    
    public class Test_demo {
    	public static void main(String[] args) {
    		String s ="jsdfsjifsifdsfdsiuujnnkmn";
    		Map<Character,Integer> result = new HashMap<Character,Integer>();
    		for(int i=0;i<s.length();i++) {
    			//挨个获取每一个字符
    			char ch =s.charAt(i);
    			
    			//如果result不为空，就走一次，给这个值加一次次数值
    			if(result.get(ch)!=null) {
    				result.put(ch,result.get(ch)+1);
    			}
    			//如果result为空，就说明该字母是第一次出现，赋值为1即可
    			else {
    				result.put(ch,1);
    			}
    		}
    		
    		//便利循环result 集合
    		for(Map.Entry<Character,Integer> en:result.entrySet()) {
    			System.out.println(en.getKey()+"—————"+en.getValue());
    		}
    	}
    }

![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3poYW5nMTUwMTE0_size_16_color_FFFFFF_t_70]

方法二：

package ceshi;
    
    public class Test_demo2 {
    	public static void main(String[] args) {
    		String str="jsdfsjifsifdsfdsiuujnnkmn";
    		char[] ch=str.toCharArray();
    		for(char i='a';i<'z';i++) {
    			int count = 0;
    			for(int j=0;j<ch.length;j++) {
    				if(i==ch[j]) {
    					count++;
    				}
    			}
    			if(count!=0) {
    				System.out.println(i+"——"+count);
    			}
    		}
    	}
    }

![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3poYW5nMTUwMTE0_size_16_color_FFFFFF_t_70 1]

原文：[https://blog.csdn.net/qq\_42249896/article/details/89407124][https_blog.csdn.net_qq_42249896_article_details_89407124]

[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3poYW5nMTUwMTE0_size_16_color_FFFFFF_t_70]: /images/20220215/f090c65a429342108f6f202819c4911b.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3poYW5nMTUwMTE0_size_16_color_FFFFFF_t_70 1]: /images/20220215/e5ad1f3cba3549c49fdbbb142037faff.png
[https_blog.csdn.net_qq_42249896_article_details_89407124]: https://blog.csdn.net/qq_42249896/article/details/89407124