package bao;

import java.io.BufferedReader;

import java.io.FileReader;

import java.io.IOException;

import java.text.NumberFormat;

public class Text2 {

     private static String formattedDecimalToPercentage(double decimal)

        {

            //获取格式化对象

            NumberFormat nt = NumberFormat.getPercentInstance();

            //设置百分数精确度2即保留两位小数

            nt.setMinimumFractionDigits(2);

            return nt.format(decimal);

        }

public static void main(String []args) {

    String a1;

    char a='A';

    int a2[]=new int[27];

    char b1[]=new char[26];

    char b2[]=new char[26];

    for(int i=0;i<26;i++)

    {

    b1[i]=a;

    b2[i]=(char)(a+32);

    a++;

    }

    for(int i=0;i<26;i++) {

        System.out.println(b1[i]);

        System.out.println(b2[i]);

    }

    try {

        BufferedReader in = new BufferedReader(new FileReader("D:\\Downloadbaidu\\2.txt"));

        String str;

        while ((str = in.readLine()) != null) {

            System.out.println(str);

            char[] d=str.toCharArray();

            for(int i=0;i<d.length-1;i++) {

                for(int j=0;j<26;j++) {

                    if(b1[j]==d[i]||b2[j]==d[i]) {

                        a2[j]++;

                    }

                }

            }

        }

        a2[26]=0;

        for(int i=0;i<26;i++) {

            a2[26]=a2[i]+a2[26];

        }

        for(int i=0;i<26;i++) {

            System.out.print(b1[i]);

            System.out.print("和");

            System.out.print(b2[i]);

            System.out.print("出现的次数为：");

            System.out.println(a2[i]);

            double d=(double)((double)a2[i]/(double)a2[26]);

            String result2=formattedDecimalToPercentage(d);

            System.out.println("result = "+result2);

        }

    } catch (IOException e) {

    }

}

}

package bao;

import java.io.BufferedReader;

import java.io.FileReader;

import java.util.*;

public class Text3 {

    public static void main(String [] args) throws Exception {

        BufferedReader br = new BufferedReader(new FileReader("D:\\Downloadbaidu\\2.txt"));

        StringBuffer sb = new StringBuffer();

        String text =null;

        while ((text=br.readLine())!= null){

            sb.append(text);// 将读取出的字符追加到stringbuffer中

        }

        br.close();  // 关闭读入流

        String str = sb.toString().toLowerCase(); // 将stringBuffer转为字符并转换为小写

        String[] words = str.split("[^(a-zA-Z)]+");  // 非单词的字符来分割，得到所有单词

        Map<String ,Integer> map = new HashMap<String, Integer>() ;

        for(String word :words){

            if(map.get(word)==null){  // 若不存在说明是第一次，则加入到map,出现次数为1

                map.put(word,1);

            }else{

                map.put(word,map.get(word)+1);  // 若存在，次数累加1

            }

        }

        // 排序

        List<Map.Entry<String ,Integer>> list = new ArrayList<Map.Entry<String,Integer>>(map.entrySet());

        Comparator<Map.Entry<String,Integer>> comparator = new Comparator<Map.Entry<String, Integer>>() {

            public int compare(Map.Entry<String, Integer> left, Map.Entry<String, Integer> right) {

                return (left.getValue().compareTo(right.getValue()));

            }

        };

        // 集合默认升序升序

        Collections.sort(list,comparator);

        for(int i=0;i<list.size();i++){// 由高到低输出

            System.out.println(list.get(list.size()-i-1).getKey() +":"+list.get(list.size()-i-1).getValue());

        }

    }