1.各种行的说明

在Java源程序中的行共有3种：

(1)代码行，可运行的Java源代码。例如：

 1 int n = 10; 

(2) 注释行，3种注释均可。例如：

1  /**
2   文档注释
3  */
4 
5  /*
6    多行注释
7  */
8  
9  //单行注释

(3)空行，既无代码，也无注释；

 1                                                                                        

2.特殊行的处理方法

如果有以下行尾单行注释的情况，将该行判定为代码行。

 1 int number; //number表示人数 2 int n; /*n表示数量*/ 

如果有以下行尾多行注释的情况，第1行判定为代码行，第二行判定为注释行。

 1 int number; /* number为整型 2 表示人数 */ 

假设被分析程序源码无其他特殊情况，如:

 1 int /*人数*/ number; 

代码实现

代码中不使用正则表达式进行简化操作,而是使用逻辑判断.
思路还是先在给定的目录下递归寻找所有的java文件,将其加入到ArrayList中.用循环对ArrayList中每一个java文件分别统计总行数,注释行数,空白行数,代码行数.虽然可以只扫描一遍文件就能得到不同的行数,但是为了代码的耦合度和美观,每个统计都分开一个方法.

构造方法

1 ArrayList<File> fileList;
2 File root;
3 public CodeAnalyzer(String pathName) {
4     root = new File(pathName);  //给定的目录
5     fileList = new ArrayList<>(); //储存java文件
6  }

递归搜索目录下的java文件

 1 public void searchFiles() {
 2 File[] files = root.listFiles();
 3 int length = files.length;
 4 for (int i = 0; i < length; i++) {
 5     if (files[i].isDirectory()) {
 6         root = files[i];
 7         searchFiles();
 8     } else {
 9         if (files[i].getName().endsWith(".java"))
10             fileList.add(files[i]);
11            }
12     }
13 }

统计单个文件的空白行数

1 public int countBlanks(File file) throws IOException {
2     BufferedReader input = new BufferedReader(new FileReader(file));
3     int blanks = 0;
4     String line = null;
5     while ((line = input.readLine()) != null) {
6         if (line.trim().equals("")) blanks++;
7     }
8     return blanks;
9 }

统计单个文件的注释行数

 1 public int countComments(File file) throws IOException {
 2     BufferedReader input = new BufferedReader(new FileReader(file));
 3     int comments = 0;
 4     String line = null;
 5     while ((line = input.readLine()) != null) {
 6         line = line.trim();
 7         if (line.startsWith("//")) { //单行注释
 8             comments++;
 9         } else if (line.startsWith("/*")) { //多行及文档注释
10             comments++;
11             while (!line.endsWith("*/")) {
12                 line = input.readLine().trim();
13                 comments++;
14             }
15         } else if (line.contains("/*")) { //行尾多行注释
16             line = input.readLine().trim();
17             if (line.endsWith("*/")) comments++;
18         }
19     }
20     return comments;
21 }

总的统计与输出

 1 public void codeAnalyze() {
 2     double rowsCount = 0;
 3     double commentsCount = 0;
 4     double blanksCount = 0;
 5     double codesCount = 0;
 6     DecimalFormat df = new DecimalFormat("#.##");
 7     for (File file : fileList) {
 8         try {
 9             rowsCount += countRows(file);
10             blanksCount += countBlanks(file);
11             commentsCount += countComments(file);
12             codesCount = rowsCount - blanksCount - commentsCount;
13         } catch (IOException e) {
14             e.printStackTrace();
15         }
16     }
17     //输出结果
18     System.out.println("源程序文件总行数:" + (int) rowsCount);
19     System.out.println("代码行数:" + (int) codesCount + ",占" + df.format(codesCount / rowsCount*100) + "%");
20     System.out.println("注释行数:" + (int) commentsCount + ",占" + df.format(commentsCount / rowsCount*100) + "%");
21     System.out.println("空白行数:" + (int) blanksCount + ",占" + df.format(blanksCount / rowsCount*100) + "%");
22 }

主函数

1 public static void main(String[] args) {
2     String pathName = "E:\\1";
3     CodeAnalyzer analyzer = new CodeAnalyzer(pathName);
4     analyzer.searchFiles(); //搜索文件
5     analyzer.codeAnalyze(); //统计文件
6 }

完整代码

  1 import java.io.*;
  2 import java.util.ArrayList;
  3 import java.text.DecimalFormat;
  4 
  5 public class CodeAnalyzer {
  6     ArrayList<File> fileList;
  7     File root;
  8 
  9     public CodeAnalyzer(String pathName) {
 10         root = new File(pathName);
 11         fileList = new ArrayList<>();
 12     }
 13 
 14     public void searchFiles() {
 15         File[] files = root.listFiles();
 16         int length = files.length;
 17         for (int i = 0; i < length; i++) {
 18             if (files[i].isDirectory()) {
 19                 root = files[i];
 20                 searchFiles();
 21             } else {
 22                 if (files[i].getName().endsWith(".java"))
 23                     fileList.add(files[i]);
 24             }
 25         }
 26     }
 27 
 28     public void codeAnalyze() {
 29         double rowsCount = 0;
 30         double commentsCount = 0;
 31         double blanksCount = 0;
 32         double codesCount = 0;
 33         DecimalFormat df = new DecimalFormat("#.##");
 34         for (File file : fileList) {
 35             try {
 36                 rowsCount += countRows(file);
 37                 blanksCount += countBlanks(file);
 38                 commentsCount += countComments(file);
 39                 codesCount = rowsCount - blanksCount - commentsCount;
 40             } catch (IOException e) {
 41                 e.printStackTrace();
 42             }
 43         }
 44         //输出结果
 45         System.out.println("源程序文件总行数:" + (int) rowsCount);
 46         System.out.println("代码行数:" + (int) codesCount + ",占" + df.format(codesCount / rowsCount * 100) + "%");
 47         System.out.println("注释行数:" + (int) commentsCount + ",占" + df.format(commentsCount / rowsCount * 100) + "%");
 48         System.out.println("空白行数:" + (int) blanksCount + ",占" + df.format(blanksCount / rowsCount * 100) + "%");
 49     }
 50 
 51     public int countRows(File file) throws IOException {
 52         BufferedReader input = new BufferedReader(new FileReader(file));
 53         int rows = 0;
 54         while (input.readLine() != null) {
 55             rows++;
 56         }
 57         return rows;
 58     }
 59 
 60     public int countBlanks(File file) throws IOException {
 61         BufferedReader input = new BufferedReader(new FileReader(file));
 62         int blanks = 0;
 63         String line = null;
 64         while ((line = input.readLine()) != null) {
 65             if (line.trim().equals("")) blanks++;
 66         }
 67         return blanks;
 68     }
 69 
 70     public int countComments(File file) throws IOException {
 71         BufferedReader input = new BufferedReader(new FileReader(file));
 72         int comments = 0;
 73         String line = null;
 74         while ((line = input.readLine()) != null) {
 75             line = line.trim();
 76             if (line.startsWith("//")) {//单行注释
 77                 comments++;
 78             } else if (line.startsWith("/*")) { //多行及文档注释
 79                 comments++;
 80                 while (!line.endsWith("*/")) {
 81                     line = input.readLine().trim();
 82                     comments++;
 83                 }
 84             } else if (line.contains("/*")) { //下行尾多行注释
 85                 line = input.readLine().trim();
 86                 if (line.endsWith("*/")) comments++;
 87             }
 88 
 89         }
 90         return comments;
 91     }
 92 
 93     public static void main(String[] args) {
 94         String pathName = "F:\\Java\\work";
 95         CodeAnalyzer analyzer = new CodeAnalyzer(pathName);
 96         analyzer.searchFiles();
 97         analyzer.codeAnalyze();
 98     }
 99 
100 }

测试结果

 

 参考项目： 代码计数器，内含有更多python打包exe文件，欢迎查阅！！！