评论区有同学提出来中文过滤的问题，之前的版本确实没有想到，请参考最新应用正则表达式过滤的版本：

package com.test;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;

public class Test {
	public static void main(String[] args) {
		try {
			showCounts();
		} catch (IOException e) {
			e.printStackTrace();
		}
	}
	
	public static void showCounts() throws IOException {
		BufferedReader br=new BufferedReader(new InputStreamReader(System.in));
		System.out.println("Please input something:");
		String str=br.readLine();
		char[] chs=str.toCharArray();
		int chineseCount=0;
		int letterCount=0;
		int digitalCount=0;
		int spaceCount=0;
		int otherCount=0;
		for(char ch:chs) {
			if((ch+"").matches("[\u4e00-\u9fa5]")) {
				chineseCount++;
			}else if((ch+"").matches("[a-zA-Z]")) {
				letterCount++;
			}else if((ch+"").matches("[0-9]")) {
				digitalCount++;
			}else if((ch+"").matches(" ")) {
				spaceCount++;
			}else {
				otherCount++;
			}
		}
		System.out.println("中文字符:"+chineseCount);
		System.out.println("英文字符:"+letterCount);
		System.out.println("数字字符:"+digitalCount);
		System.out.println("空格字符:"+spaceCount);
		System.out.println("其他字符:"+otherCount);
	}
}

console测试

这是朴实无华的分割线，下面的代码已过时

package t6;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;

public class Test {
	public static void test() {
		BufferedReader br=new BufferedReader(new InputStreamReader(System.in));
		String str="";
		System.out.println("请输入一行字符：");
		try {
			str = br.readLine();
		} catch (IOException e) {
			e.printStackTrace();
		}
		char[] charArr=str.toCharArray();
		int letterCount=0;
		int spaceCount=0;
		int digitalCount=0;
		int otherCount=0;
		for(char ch:charArr) {
			if(Character.isLetter(ch)) {
				letterCount++;
			}else if(Character.isSpace(ch)) {
				spaceCount++;
			}else if(Character.isDigit(ch)) {
				digitalCount++;
			}else {
				otherCount++;
			}
		}
		System.out.println("英文字数："+letterCount);
		System.out.println("空格字数："+spaceCount);
		System.out.println("数字字数："+digitalCount);
		System.out.println("其他字数："+otherCount);
	}
}