软件工程作业二：WordCount实现与改进

首先，我在网上找了一个WordCount的源码，在源码上进行修改

原文博主：波涛汹涌

原文链接：http://blog.sina.com.cn/s/blog_51335a000101ouzf.html

原文代码：

wordCountDemo

原文的代码实现读取文件，统计所有出现过的单词（不重复），并统计打印每个单词出现的次数。代码导入包时有两个错误。且打印存在重复，输出不好看。

修改后的代码：

import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.ArrayList;
import java.util.Collections;
import java.util.HashMap;
import java.util.HashSet;
import java.util.List;
import java.util.Map;
import java.util.Set;
import java.util.TreeMap;

/**
 * 
 * @author 张军洪 
 * original author：波涛汹涌
 * http://blog.sina.com.cn/s/blog_51335a000101ouzf.html
 *
 */

public class WordCount {
    private static String path_src = "C:/Users/张军洪/Desktop/shenma.txt";
    private static String path_result = "C:/Users/张军洪/Desktop/shenma_result.txt";
    private static BufferedReader br = null;
    private static BufferedWriter bw = null;
    private static String line_current = null;
    private static String[] words = null;
    private static List<String> word_list = new ArrayList<String>();  //所有出现的单词(不重复)
    static int countWord=0;
    static int countChar=0;
    static int countLine=0;
    static String s="";
    static String strCount="";
    
    public static void main(String[] args) {

        File file = new File(path_src); // 读取文件

        // 错误处理
        if (!file.exists()) {
            System.out.println("file " + file + " is not existed, exit");
            return;
        }
        try {
            br = new BufferedReader(new FileReader(file.getPath()));
            line_current = br.readLine();
            while (line_current != null) {
                words = line_current.split(" |,|\\.");
                for (String s : words) {
                    if (!s.equals(""))
                        word_list.add(s);
                }

                line_current = br.readLine();
            }

            // 打印单词
            for (String temp : word_list) {
                System.out.println(temp);
            }
             br = new BufferedReader(new InputStreamReader(new FileInputStream(new File(path_src))));
             while((s=br.readLine())!=null)
              {
                 s=s+" ";
                 strCount+=s;
               countLine++;
              }
             for(int i=0;i<strCount.split(" ").length;i++){
                 if(!strCount.split(" ")[i].equals(" "))
                     countWord++;
                 countChar+= strCount.split(" ")[i].length();
             } 
             System.out.println();
//             System.out.println("单词数："+countWord);
//             System.out.println("字符数："+countChar);
//             System.out.println("行数："+countLine);
//             System.out.println();

            // HashSet
            Set<String> hashSet = new HashSet<String>(word_list);
//            for (String str : hashSet) {
//                System.out.println("word: " + str + ", occur times: " + Collections.frequency(word_list, str));
//            }

            // HashMap
            Map<String, Integer> hashMap = new HashMap<String, Integer>();
            for (String temp : word_list) {
                Integer count = hashMap.get(temp);
                hashMap.put(temp, (count == null) ? 1 : count + 1);
            }

            // TreeMap
            TreeMap<String, Integer> treeMap = new TreeMap<String, Integer>(hashMap);

            // Record result to another file
            printMap(treeMap);
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            closeInputStream(br);
            closeOutputStream(bw);
        }
    }

    //将数据写入文件（两种打印方式）
    public static void printMap(Map<String, Integer> map) throws IOException {

        bw = new BufferedWriter(new FileWriter(path_result));

        Set<String> keys = map.keySet();
        for (String s : keys) {
            System.out.println("word: " + s + ", times: " + map.get(s));
            writeResult("word: " + s + ", times: " + map.get(s));
        }
        System.out.println();
        System.out.println("单词数目：" + countWord);
        writeResult(String.valueOf(countWord));
        System.out.println("字符数目：" + countChar);
        writeResult(String.valueOf(countChar));
        System.out.println("行数：" + countLine);
        writeResult(String.valueOf(countLine));
//        for (Map.Entry<String, Integer> entry : map.entrySet()) {
//            System.out.println("word: " + entry.getKey() + ", number : " + entry.getValue());
//            writeResult("word: " + entry.getKey() + ", number : " + entry.getValue());
//        }

    }

    //写入函数
    public static void writeResult(String line) throws IOException {

        try {
            if (bw != null) {
                bw.write(line);
                bw.newLine();
                bw.flush();
            }
        } catch (IOException e) {
            e.printStackTrace();
            closeOutputStream(bw);
        }
    }

    public static void closeOutputStream(BufferedWriter writer) {
        try {
            if (writer != null) {
                writer.close();
            }
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    public static void closeInputStream(BufferedReader reader) {
        try {
            if (reader != null) {
                reader.close();
            }
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

经过修改的代码在原有功能的基础上，添加了能够统计单词数目，字符数目，文件行数的功能。优化输出打印方式，使结果查看更简单。