在Java中的包中获取类文件的数组 [英] Get a array of class files inside a package in Java

问题描述

我需要一个包含在我的源代码包中的所有类文件的Class []。

我找不到标准方法它在一枪。如果有人可以编写一个函数来获取该列表，将会非常有帮助。

  Class [] myClasses = yourfunction //返回当前工作项目中源代码包中的类的列表$ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ $ 

我能够使用正常的文件I / O和搜索机制解决这个问题。您可以检查此处发布的答案。

  private static List< Class> getClassesForPackage（Package pkg）{
 String pkgname = pkg.getName（）; 
 
 List< Class> classes = new ArrayList< Class>（）; 
 
 //获取包的文件对象
文件目录= null; 
 String fullPath; 
 String relPath = pkgname.replace（'。'，'/'）; 
 
 //System.out.println(\"ClassDiscovery：Package：+ pkgname +变成Path：+ relPath）; 
 
 URL resource = ClassLoader.getSystemClassLoader（）。getResource（relPath）; 
 
 //System.out.println(\"ClassDiscovery：Resource =+ resource）; 
 if（resource == null）{
 throw new RuntimeException（No resource for+ relPath）; 
} 
 fullPath = resource.getFile（）; 
 //System.out.println(\"ClassDiscovery：FullPath =+ resource）; 
 
 try {
 directory = new File（resource.toURI（））; 
} catch（URISyntaxException e）{
 throw new RuntimeException（pkgname +（+ resource +）看起来不是有效的URL / URI。 ..，e）; 
} catch（IllegalArgumentException e）{
 directory = null; 
} 
 //System.out.println(\"ClassDiscovery：Directory =+ directory）; 
 
 if（directory！= null&& directory.exists（））{
 
 //获取包中包含的文件的列表
 String [] files = directory.list（）; 
 for（int i = 0; i< files.length; i ++）{
 
 //我们只对.class文件感兴趣
 if（files [i]。 endsWith（。class））{
 
 //删除.class扩展
 String className = pkgname +'。'+ files [i] .substring（0，files [i] .length（） -  6）; 
 
 //System.out.println(\"ClassDiscovery：className =+ className）; 
 
 Try {
 classes.add（Class.forName（className））; 
} catch（ClassNotFoundException e）{
 throw new RuntimeException（ClassNotFoundException loading+ className）; 
} 
} 
} 
} else {
 try {
 String jarPath = fullPath.replaceFirst（[。] jar [！]。* ，.jar）。replaceFirst（file：，）; 
 JarFile jarFile = new JarFile（jarPath）; 
枚举< JarEntry> entries = jarFile.entries（）; 
 while（entries.hasMoreElements（））{
 JarEntry entry = entries.nextElement（）; 
 String entryName = entry.getName（）; 
 if（entryName.startsWith（relPath）&& entryName.length（）>（relPath.length（）+/。length（）））{
 
 System.out.println（ClassDiscovery：JarEntry：+ entryName）; 
 String className = entryName.replace（'/'，'。'）。replace（'\\'，'。'）。replace（。class，）; 
 
 //System.out.println(\"ClassDiscovery：className =+ className）; 
 try {
 classes.add（Class.forName（className））; 
} catch（ClassNotFoundException e）{
 throw new RuntimeException（ClassNotFoundException loading+ className）; 
} 
} 
} 
} catch（IOException e）{
 throw new RuntimeException（pkgname +（+ directory +）有效包，e）; 
} 
} 
返回类; 
} 
  




I need a Class[] of all the class files contained in one of my source packages in Java.

I could n't find a standard method to do it in one shot. If someone can write a function to fetch that list would be really helpful.

Class[] myClasses = yourfunction();  // Return a list of class inside a source package in the currently working project in java

解决方案

I am able to solve this problem using normal file I/O and search mechanism. You can check the answer as posted here.

private static List<Class> getClassesForPackage(Package pkg) {
    String pkgname = pkg.getName();

    List<Class> classes = new ArrayList<Class>();

    // Get a File object for the package
    File directory = null;
    String fullPath;
    String relPath = pkgname.replace('.', '/');

    //System.out.println("ClassDiscovery: Package: " + pkgname + " becomes Path:" + relPath);

    URL resource = ClassLoader.getSystemClassLoader().getResource(relPath);

    //System.out.println("ClassDiscovery: Resource = " + resource);
    if (resource == null) {
        throw new RuntimeException("No resource for " + relPath);
    }
    fullPath = resource.getFile();
    //System.out.println("ClassDiscovery: FullPath = " + resource);

    try {
        directory = new File(resource.toURI());
    } catch (URISyntaxException e) {
        throw new RuntimeException(pkgname + " (" + resource + ") does not appear to be a valid URL / URI.  Strange, since we got it from the system...", e);
    } catch (IllegalArgumentException e) {
        directory = null;
    }
    //System.out.println("ClassDiscovery: Directory = " + directory);

    if (directory != null && directory.exists()) {

        // Get the list of the files contained in the package
        String[] files = directory.list();
        for (int i = 0; i < files.length; i++) {

            // we are only interested in .class files
            if (files[i].endsWith(".class")) {

                // removes the .class extension
                String className = pkgname + '.' + files[i].substring(0, files[i].length() - 6);

                //System.out.println("ClassDiscovery: className = " + className);

                try {
                    classes.add(Class.forName(className));
                } catch (ClassNotFoundException e) {
                    throw new RuntimeException("ClassNotFoundException loading " + className);
                }
            }
        }
    } else {
        try {
            String jarPath = fullPath.replaceFirst("[.]jar[!].*", ".jar").replaceFirst("file:", "");
            JarFile jarFile = new JarFile(jarPath);
            Enumeration<JarEntry> entries = jarFile.entries();
            while (entries.hasMoreElements()) {
                JarEntry entry = entries.nextElement();
                String entryName = entry.getName();
                if (entryName.startsWith(relPath) && entryName.length() > (relPath.length() + "/".length())) {

                    //System.out.println("ClassDiscovery: JarEntry: " + entryName);
                    String className = entryName.replace('/', '.').replace('\\', '.').replace(".class", "");

                    //System.out.println("ClassDiscovery: className = " + className);
                    try {
                        classes.add(Class.forName(className));
                    } catch (ClassNotFoundException e) {
                        throw new RuntimeException("ClassNotFoundException loading " + className);
                    }
                }
            }
        } catch (IOException e) {
            throw new RuntimeException(pkgname + " (" + directory + ") does not appear to be a valid package", e);
        }
    }
    return classes;
}

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