java 解析路径下的.java文件并获取改动类

要解析路径下的.java文件并获取改动类，可以使用Java编写一个程序来实现。下面是一个简单的实现：

1. 首先需要获取该路径下的所有.java文件，可以使用Java的File类来实现：

File folder = new File("path/to/folder");
File[] files = folder.listFiles(new FilenameFilter() {
    public boolean accept(File dir, String name) {
        return name.endsWith(".java");
    }
});

2. 对于每个文件，需要读取其内容并解析其中的类声明。可以使用Java的Scanner类来读取文件内容，并使用正则表达式来匹配类声明：

Scanner scanner = new Scanner(file);
String content = scanner.useDelimiter("\\Z").next();
scanner.close();

Pattern pattern = Pattern.compile("class\\s+([a-zA-Z_][a-zA-Z0-9_]*)\\s*\\{");
Matcher matcher = pattern.matcher(content);

while (matcher.find()) {
    String className = matcher.group(1);
    // 处理类名
}

3. 为了确定哪些类发生了改动，可以使用版本控制工具（如Git）来比较代码库中的版本和当前文件的版本。可以使用Java的ProcessBuilder类来执行Git命令：

ProcessBuilder builder = new ProcessBuilder("git", "diff", "--name-only", "HEAD", file.getAbsolutePath());
Process process = builder.start();

if (process.waitFor() == 0) {
    BufferedReader reader = new BufferedReader(new InputStreamReader(process.getInputStream()));
    String line;

    while ((line = reader.readLine()) != null) {
        if (line.endsWith(".java")) {
            String changedClassName = line.substring(line.lastIndexOf(File.separatorChar) + 1, line.lastIndexOf('.'));
            // 处理改动的类名
        }
    }
}

4. 综合以上步骤，可以写出完整的程序：

import java.io.*;
import java.util.regex.*;

public class JavaFileParser {
    public static void main(String[] args) throws Exception {
        File folder = new File("path/to/folder");
        File[] files = folder.listFiles(new FilenameFilter() {
            public boolean accept(File dir, String name) {
                return name.endsWith(".java");
            }
        });

        for (File file : files) {
            Scanner scanner = new Scanner(file);
            String content = scanner.useDelimiter("\\Z").next();
            scanner.close();

            Pattern pattern = Pattern.compile("class\\s+([a-zA-Z_][a-zA-Z0-9_]*)\\s*\\{");
            Matcher matcher = pattern.matcher(content);

            while (matcher.find()) {
                String className = matcher.group(1);

                ProcessBuilder builder = new ProcessBuilder("git", "diff", "--name-only", "HEAD", file.getAbsolutePath());
                Process process = builder.start();

                if (process.waitFor() == 0) {
                    BufferedReader reader = new BufferedReader(new InputStreamReader(process.getInputStream()));
                    String line;

                    while ((line = reader.readLine()) != null) {
                        if (line.endsWith(".java")) {
                            String changedClassName = line.substring(line.lastIndexOf(File.separatorChar) + 1, line.lastIndexOf('.'));
                            if (changedClassName.equals(className)) {
                                System.out.println(className + " in " + file.getAbsolutePath() + " has changed.");
                                break;
                            }
                        }
                    }
                }
            }
        }
    }
}