需求概要

1.读取文件,文件内包可含英文字符,及常见标点,空格级换行符。

2.统计英文单词在本文件的出现次数

3.将统计结果排序

4.显示排序结果

分析

1.读取文件可使用BufferedReader类按行读取

2.针对读入行根据分隔符拆分出单词,使用java.util工具提供的Map记录单词和其出现次数的信息,HashMap和TreeMap均可,如果排序结果按字母序可选用TreeMap,本例选择用HashMap。

3.将Map中存储的键值对,存入List中,List中的元素为二维字符串数组,并将单词出现次数作为比对依据,利用list提供的sort方法排序,需要实现Comparator.compare接口方法。

4.循环遍历List中的String[],输出结果。

部分功能实现

输出结果

 public void printSortedWordGroupCount(String filename) {
  List<String[]> result = getSortedWordGroupCount(filename);
  if (result == null) {
    System.out.println("no result");
  return;
  }
  for (String[] sa : result) {
    System.out.println(sa[1] + ": " + sa[0]);
  }
}

统计

 public Map<String, Integer> getWordGroupCount(String filename) {
  try {
  FileReader fr = new FileReader(filename);
  BufferedReader br = new BufferedReader(fr);
  String content = "";
  Map<String, Integer> result = new HashMap<String, Integer>();
  while ((content = br.readLine()) != null) {
    StringTokenizer st = new StringTokenizer(content, "!&(){}+-= ':;<> /\",");
    while (st.hasMoreTokens()) {
    String key = st.nextToken();
    if (result.containsKey(key))
      result.put(key, result.get(key) + 1);
    else
      result.put(key, 1);
    }
  }
  br.close();
  fr.close();
  return result;   } catch (FileNotFoundException e) {
    System.out.println("failed to open file:" + filename);
    e.printStackTrace();
  } catch (Exception e) {
    System.out.println("some expection occured");
    e.printStackTrace();
  }
    return null;
}

排序

     public List<String[]> getSortedWordGroupCount(String filename) {
Map<String, Integer> result = getWordGroupCount(filename);
if (result == null)
return null;
List<String[]> list = new LinkedList<String[]>();
Set<String> keys = result.keySet();
Iterator<String> iter = keys.iterator();
while (iter.hasNext()) {
String key = iter.next();
String[] item = new String[2];
item[1] = key;
item[0] = "" + result.get(key);
list.add(item);
}
list.sort(new Comparator<String[]>() {
public int compare(String[] s1, String[] s2) {
return Integer.parseInt(s2[0])-Integer.parseInt(s1[0]); }
});
return list;
}

针对本程序的简易测试用例自动生成

使用随机数产生随机单词,空格,并在随机位置插入回车

 public boolean gernerateWordList(String filePosition, long wordNum) {
  FileWriter fw = null;
  StringBuffer sb = new StringBuffer("");
  try {
    fw = new FileWriter(filePosition);     for (int j = 0; j < wordNum; j++) {
    int length = (int) (Math.random() * 10 + 1);
    for (int i = 0; i < length; i++) {
      char ch = (char) ('a' + (int) (Math.random() * 26));
      sb.append(ch);
    }
    fw.write(sb.toString());
    fw.write(" ");
    sb = new StringBuffer("");
    if (wordNum % (int) (Math.random() * 8 + 4) == 0)
      fw.write("\n");
    }
  } catch (IOException e) {
    e.printStackTrace();
    return false;
  } finally {
    try {
      fw.close();
    } catch (IOException e) {
      e.printStackTrace();
      System.out.println("failed to close file");
      return false;
    }
   }
   return false;
  }
}

实际用例结果

源自维基百科specification词条节选

"Specification" redirects here. For other uses, see Specification (disambiguation).
There are different types of specifications, which generally are mostly types of documents, forms or orders or relates to information in databases. The word specification is defined as "to state explicitly or in detail" or "to be specific". A specification may refer to a type of technical standard (the main topic of this page). Using a word "specification" without additional information to what kind of specification you refer to is confusing and considered bad practice within systems engineering. A requirement specification is a set of documented requirements to be satisfied by a material, design, product, or service.[1] A functional specification is closely related to the requirement specification and may show functional block diagrams. A design or product specification describes the features of the solutions for the Requirement Specification, referring to the designed solution or final produced solution. Sometimes the term specification is here used in connection with a data sheet (or spec sheet). This may be confusing. A data sheet describes the technical characteristics of an item or product as designed and/or produced. It can be published by a manufacturer to help people choose products or to help use the products. A data sheet is not a technical specification as described in this article. A "in-service" or "maintained as" specification, specifies the conditions of a system or object after years of operation, including the effects of wear and maintenance (configuration changes). Specifications may also refer to technical standards, which may be developed by any of various kinds of organizations, both public and private. Example organization types include a corporation, a consortium (a small group of corporations), a trade association (an industry-wide group of corporations), a national government (including its military, regulatory agencies, and national laboratories and institutes), a professional association (society), a purpose-made standards organization such as ISO, or vendor-neutral developed generic requirements. It is common for one organization to refer to (reference, call out, cite) the standards of another. Voluntary standards may become mandatory if adopted by a government or business contract.

  

结果截取

a:  16
of: 16
or: 15
to: 14
the: 12
specification: 11
is: 7
A: 7
and: 7
may: 6
in: 5
.: 5
as: 5
be: 5
standards: 4
by: 4
technical: 4
sheet: 4
refer: 4
product: 3
Specification: 3
organization: 3
data: 3
types: 3
an: 2
word: 2
functional: 2
association: 2
It: 2
government: 2
are: 2
national: 2
describes: 2
help: 2
information: 2
developed: 2
group: 2
which: 2
including: 2
this: 2
corporations: 2
for: 2
design: 2
designed: 2
requirement: 2
mostly: 1
practice: 1
bad: 1
products.: 1
considered: 1
type: 1
without: 1
years: 1
professional: 1

  

可进行的拓展

建立重载函数,添加参数,可以根据用户需要倒序排列统计结果,即按照单词出现次数从少到多排序。

工程源码包地址https://coding.net/u/jx8zjs/p/wordCount/git

git@git.coding.net:jx8zjs/wordCount.git

英文词频统计的java实现方法的更多相关文章

  1. 词频统计的java实现方法——第一次改进

    需求概要 原需求 1.读取文件,文件内包可含英文字符,及常见标点,空格级换行符. 2.统计英文单词在本文件的出现次数 3.将统计结果排序 4.显示排序结果 新需求: 1.小文件输入. 为表明程序能跑 ...

  2. 效能分析——词频统计的java实现方法的第一次改进

    java效能分析可以使用JProfiler 词频统计处理的文件为WarAndPeace,大小3282KB约3.3MB,输出结果到文件 在程序本身内开始和结束分别加入时间戳,差值平均为480-490ms ...

  3. Python——字符串、文件操作,英文词频统计预处理

    一.字符串操作: 解析身份证号:生日.性别.出生地等. 凯撒密码编码与解码 网址观察与批量生成 2.凯撒密码编码与解码 凯撒加密法的替换方法是通过排列明文和密文字母表,密文字母表示通过将明文字母表向左 ...

  4. 组合数据类型,英文词频统计 python

    练习: 总结列表,元组,字典,集合的联系与区别.列表,元组,字典,集合的遍历. 区别: 一.列表:列表给大家的印象是索引,有了索引就是有序,想要存储有序的项目,用列表是再好不过的选择了.在python ...

  5. Hadoop的改进实验(中文分词词频统计及英文词频统计)(4/4)

    声明: 1)本文由我bitpeach原创撰写,转载时请注明出处,侵权必究. 2)本小实验工作环境为Windows系统下的百度云(联网),和Ubuntu系统的hadoop1-2-1(自己提前配好).如不 ...

  6. 1.字符串操作:& 2.英文词频统计预处理

    1.字符串操作: 解析身份证号:生日.性别.出生地等. ID = input('请输入十八位身份证号码: ') if len(ID) == 18: print("你的身份证号码是 " ...

  7. Programming | 中/ 英文词频统计(MATLAB实现)

    一.英文词频统计 英文词频统计很简单,只需借助split断句,再统计即可. 完整MATLAB代码: function wordcount %思路:中文词频统计涉及到对"词语"的判断 ...

  8. python字符串操作、文件操作,英文词频统计预处理

    1.字符串操作: 解析身份证号:生日.性别.出生地等. 凯撒密码编码与解码 网址观察与批量生成 解析身份证号:生日.性别.出生地等 def function3(): print('请输入身份证号') ...

  9. python复合数据类型以及英文词频统计

    这个作业的要求来自于:https://edu.cnblogs.com/campus/gzcc/GZCC-16SE1/homework/2753. 1.列表,元组,字典,集合分别如何增删改查及遍历. 列 ...

随机推荐

  1. 【转】Win10/UWP新特性系列—Web

    Internet Explorer Internet Explorer 在Windows 10 升级为Edge模式,是一种交互性和兼容性都很强的新型浏览器,该浏览器相比以前的版本更新了超过2000个操 ...

  2. Maven Java项目添加Scala语言支持

    为了在一个普通的使用Maven构建的Java项目中,增加对Scala语言的支持.使得其能够同时编译Java和Scala语言的文件.其实很简单的一件事情,只需要在pom.xml文件中的build部分中的 ...

  3. 安装OpenvSwitch (ovs)

    简介 搭建SDN环境少不了SDN交换机,SDN交换机跟普通交换机最大的区别就是将普通交换机的数据平面和控制平面相分离,SDN交换机只负责数据的转发,而控制指令则由更上一级的控制器下发. Open vS ...

  4. 静态成员变量和静态成员函数(static)

    数据成员可以分静态变量.非静态变量两种. 静态成员:静态类中的成员加入static修饰符,即是静态成员.可以直接使用类名+静态成员名访问此静态成员,因为静态成员存在于内存,非静态成员需要实例化才会分配 ...

  5. X5webview去掉分享功能和缓存功能

    x5webview比原生的webview适配更好,加载更快,对音视频的兼容性更好,具备独特的优势 1) 速度快:相比系统webview的网页打开速度有30+%的提升: 2) 省流量:使用云端优化技术使 ...

  6. android 图片二维码识别和保存(二)

    续上一篇,开发图片二维码识别功能后,我们对功能进行性能分析内存占用显著提高了,不使用该功能内存占用大约是147M,使用这个功能多次以后,高达203M. 因此对功能进行研究,发现每次生成的图片没有即时的 ...

  7. Jmeter+Ant+Jenkins持续集成方案改进

    关于Jmeter+Ant+Jenkins如何搭建持续集成环境,网上资料一大把,就不多说了,本文主要谈一下期间的问题及扩展该持续集成方案. 其实核心的流程不复杂,Jenkins管理构建项目,Ant配置脚 ...

  8. TPO-21 C1 Find a building for orientation

    TPO-21 C1 Find a building for orientation 第 1 段 1.Listen to a conversation between a student and a p ...

  9. Netty源码分析第5章(ByteBuf)---->第1节: AbstractByteBuf

    Netty源码分析第五章: ByteBuf 概述: 熟悉Nio的小伙伴应该对jdk底层byteBuffer不会陌生, 也就是字节缓冲区, 主要用于对网络底层io进行读写, 当channel中有数据时, ...

  10. AS的使用技巧

    title: AS的使用技巧 date: 2016-04-01 23:34:11 tags: [AndroidStudio] categories: [Tool,IDE] --- 概述 本文记录如何使 ...