这是什么啊

//: ClassScanner.java// Scans all files in directory for classes// and identifiers, to check capitalization.// Assumes properly compiling code listings.// Doesn't do everything right, but is a very// useful aid.import java.io.*;import java.util.*;class MultiStringMap extends Hashtable{public void add(String key, String value){if (!containsKey(key))put(key, new Vector());((Vector) get(key)).addElement(value);}public Vector getVector(String key){if (!containsKey(key)){System.err.println("ERROR: can't find key: " + key);System.exit(1);}return (Vector) get(key);}public void printValues(PrintStream p){Enumeration k = keys();while (k.hasMoreElements()){String oneKey = (String) k.nextElement();Vector val = getVector(oneKey);for (int i = 0; i < val.size(); i++)p.println((String) val.elementAt(i));}}}public class ClassScanner{private File path;private String[] fileList;private Properties classes = new Properties();private MultiStringMap classMap = new MultiStringMap(), identMap = new MultiStringMap();private StreamTokenizer in;public ClassScanner(){path = new File(".");fileList = path.list(new JavaFilter());for (int i = 0; i < fileList.length; i++){System.out.println(fileList[i]);scanListing(fileList[i]);}}void scanListing(String fname){try{in = new StreamTokenizer(new BufferedReader(new FileReader(fname)));// Doesn't seem to work:// in.slashStarComments(true);// in.slashSlashComments(true);in.ordinaryChar('/');in.ordinaryChar('.');in.wordChars('_', '_');in.eolIsSignificant(true);while (in.nextToken() != StreamTokenizer.TT_EOF){if (in.ttype == '/')eatComments();elseif (in.ttype == StreamTokenizer.TT_WORD){if (in.sval.equals("class") || in.sval.equals("interface")){// Get class name:while (in.nextToken() != StreamTokenizer.TT_EOF && in.ttype != StreamTokenizer.TT_WORD);classes.put(in.sval, in.sval);classMap.add(fname, in.sval);}if (in.sval.equals("import") || in.sval.equals("package"))discardLine();else// It's an identifier or keywordidentMap.add(fname, in.sval);}}}catch (IOException e){e.printStackTrace();}}void discardLine(){try{while (in.nextToken() != StreamTokenizer.TT_EOF && in.ttype != StreamTokenizer.TT_EOL); // Throw away tokens to end of line}catch (IOException e){e.printStackTrace();}}// StreamTokenizer's comment removal seemed// to be broken. This extracts them:void eatComments(){try{if (in.nextToken() != StreamTokenizer.TT_EOF){if (in.ttype == '/')discardLine();elseif (in.ttype != '*')in.pushBack();elsewhile (true){if (in.nextToken() == StreamTokenizer.TT_EOF)break;if (in.ttype == '*')if (in.nextToken() != StreamTokenizer.TT_EOF && in.ttype == '/')break;}}}catch (IOException e){e.printStackTrace();}}public String[] classNames(){String[] result = new String[classes.size()];Enumeration e = classes.keys();int i = 0;while (e.hasMoreElements()){result[i++] = (String) e.nextElement();}return result;}public void checkClassNames(){Enumeration files = classMap.keys();while (files.hasMoreElements()){String file = (String) files.nextElement();Vector cls = classMap.getVector(file);for (int i = 0; i < cls.size(); i++){String className = (String) cls.elementAt(i);if (Character.isLowerCase(className.charAt(0)))System.out.println("class capitalization error, file: " + file + ", class: " + className);}}}public void checkIdentNames(){Enumeration files = identMap.keys();Vector reportSet = new Vector();while (files.hasMoreElements()){String file = (String) files.nextElement();Vector ids = identMap.getVector(file);for (int i = 0; i < ids.size(); i++){String id = (String) ids.elementAt(i);if (!classes.contains(id)){// Ignore identifiers of length 3 or// longer that are all uppercase// (probably static final values):if (id.length() >= 3 && id.equals(id.toUpperCase()))continue;// Check to see if first char is upper:if (Character.isUpperCase(id.charAt(0))){if (reportSet.indexOf(file + id) == -1){ // Not reported yetreportSet.addElement(file + id);System.out.println("Ident capitalization error in:" + file + ", ident: " + id);}}}}}}static final String usage = "Usage: /n" + "ClassScanner classnames -a/n" + "/tAdds all the class names in this /n"+ "/tdirectory to the repository file /n" + "/tcalled 'classnames'/n" + "ClassScanner classnames/n" + "/tChecks all the java files in this /n" + "/tdirectory for capitalization errors, /n" + "/tusing the repository file 'classnames'";private static void usage(){System.err.println(usage);System.exit(1);}public static void main(String[] args){if (args.length < 1 || args.length > 2)usage();ClassScanner c = new ClassScanner();File old = new File(args[0]);if (old.exists()){try{// Try to open an existing // properties file:InputStream oldlist = new BufferedInputStream(new FileInputStream(old));c.classes.load(oldlist);oldlist.close();}catch (IOException e){System.err.println("Could not open " + old + " for reading");System.exit(1);}}if (args.length == 1){c.checkClassNames();c.checkIdentNames();}// Write the class names to a repository:if (args.length == 2){if (!args[1].equals("-a"))usage();try{BufferedOutputStream out = new BufferedOutputStream(new FileOutputStream(args[0]));c.classes.save(out, "Classes found by ClassScanner.java");out.close();}catch (IOException e){System.err.println("Could not write " + args[0]);System.exit(1);}}}}class JavaFilter implements FilenameFilter{public boolean accept(File dir, String name){// Strip path information:String f = new File(name).getName();return f.trim().endsWith(".java");}}