用JAVA写了一个简单的JS代码格式化工具

用JAVA写了一个简单的JS代码格式化工具 Section I: 为什么写这个小玩意 1. 手上有些JS代码,因为某种原因,起代码中没有任何回车、制符。在编辑器中打开时,显示的就是一行。而我实现想研究和学习这些写得比较漂亮的JS 代码, 2. 可是好想没有哪个编辑器自带了JS格式化的功能。它们都可以给JS着色,但就是不能控制代码格式,真是遗憾。 3. 我是我去网上搜看有没有前人做过这个东东,发现有个JS写的JS代码格式化工具,相当不错,可以给代码格式化,还可以着色。只不过结果都是显示在网页上,复制下来的时候那些制表符都没有了,所以贴到编辑器中时,代码还是比较混乱;而且这个每次只能格式话一个文件,还得自己手动去Copy & paste;而且因为是JS写的,速度也受到了不小的限制; 基于以上原因,我准备自己些一个小工具来格式化我需要的代码: Section II: 功能 1. 因为很多编辑器都有JS的着色功能,所一我需要的仅仅是一个格式化功能而已,那就是主要将那种故意将代码中的空白符去掉的的JS加上换行、制表符等等。 大概有一下几种情况: 1). add /n/n before "function"; 2). add /n after ";" (Except "for", and ";" between " " which is part of a string in javascript. ) and /t before the next line; 3). add "/n" and "/t" after "{"; 4). add "/n" and "/t" before "}". 2. 不仅可以格式话一个给定的文件,还可以格式化给定的一个文件夹里的所有的JS文件。这个就是通过传给Main函数的参数来实现的。参数可以如下: 1)格式化一个文件: -f path/file.js 或者: --file path/file.js 2) 格式化给定的一个文件夹里的所有的JS文件 -d path/directory 或者: --directory path/directory 举例:要格式化/home/newweapon/js/ 这个文件夹中的所有JS文件,可一使用如下命令: Jsformatter -d /home/newweapon/js Section III 缺陷 目前写的这个程序还是一个比较脆弱的程序。有很多情况没有考虑到,我在注释中把我想到的需要提高的基本都提了一下。但是因为我写这个小玩意主要是想把 我自己下的一些JS代码格式化一下,而这个对我来说已经够用了,再加上自己的水平有限,所以没有将它写得很完美。等以后有时间了,再对这个程序做一些更新。 Section IV 代码 /** * cn.newweapon.Jsformatter */ package cn.newweapon; import java.io.File; import java.io.FileReader; import java.io.FileWriter; import java.io.FilenameFilter; import java.io.IOException; import java.util.ArrayList; import java.util.Iterator; import java.util.list; import java.util.regex.Pattern; /** * @author Newweapon @ ustc [Email: newweapon111 (at) gmail.com] * @version 0.0.1 * @Created 20071015 * * @TODO 1. user can specify the formatted file name;
* 2. User can located the formatted files to a specified fo lder.
* 3. If a file is formatted partly already. Delete all blan k characters first, and then format the file.
*/ public class JsFormatter { /* ============ constants begin =================== */ /** Usage */ public static String USAGE = "Usage: JsFormatter -d path/direct ory JsFormatter -f path/filename.js"; /** Type: Directory = "0"; File = "1" */ public interface Type { /** Directory: 0 */ public static String DIRECTORY = "0"; /** File: 1 */ public static String FILE = "1"; } /* ============ constants end =================== */ /** * Entry point of the project. * * @param args Like "-d /path/directory" or "-f /path/file.js" */ public static void main(String[] args) { String startMsg = "Processing..."; String finishMsg = "Finished."; // Parameters check. if(args.length != 2) { System.err.println(USAGE); return; } // get the two parameters. String type = args[0]; String path = args[1]; // Parameters check. if("-d".equals(type) || "--directory".equals(type)) { type = Type.DIRECTORY; } else if("-f".equals(type) || "--file".equals(type)) { type = Type.FILE; } else { System.err.println(USAGE); return; } // Check file type if(Type.FILE.equals(type)) { if(path.length() <= 3 || !isJsFile(path)) { System.err.println("The file must be a JS file."); return; } } // Start message System.out.println(startMsg); // format file(s) try { if(Type.FILE.equals(type)) { formatFile(path); } else { List jsFilelist = getJsFileList(path); Iterator it = jsFilelist.iterator(); while(it.hasNext()) { formatFile(it.next()); } finishMsg += " (" + jsFileList.size() + " file(s) fo rmatted)"; } } catch (Exception e) { e.printStackTrace(); return; } // Finish message System.out.println(finishMsg); } /** * format a JS file. * * @param fileName The file name of the file which is to be form atted. * @return String The formatted string. * @throws IOException Exception when open, read and write file. */ private static void formatFile(String fileName) throws IOExcepti on { String formattedFileName = fileName + ".formatted"; FileReader fr = new FileReader(fileName); FileWriter fw = new FileWriter(formattedFileName); String lastWord = ""; int forCount = 0; int quoteCount = 0; int sigleQuoteCount = 0; int bracketCount = 0; int thisChar = 0; int lastChar = 0; int nextChar = 0; thisChar = fr.read(); if(thisChar != -1) { nextChar = fr.read(); } while(thisChar != -1) { // find and replace switch(thisChar) { // 2. add after ";" (Except "for", and ";" between " " which is part of a string in javascript. ) and before the next li ne case ';': // If the ";" is in quote or in "for", then not print " " if(quoteCount > 0 || sigleQuoteCount > 0 || forC ount > 0) { fw.write(';'); if(forCount > 0) { forCount--; } // Add " " after ";" } else { fw.write(';'); if(' ' != nextChar && ' ' != nextChar) { fw.write(' '); fillTableChar(fw, bracketCount); } } break; case '{': // 3. add " " and " " after "{" bracketCount++; fw.write('{'); if(' ' != nextChar && ' ' != nextChar) { // If the file is already formatted, don't add af ter {. fw.write(' '); fillTableChar(fw, bracketCount); } break; case '}': // 4. add " " and " " before "}" bracketCount--; fw.write(' '); fillTableChar(fw, bracketCount); fw.write('}'); if(';' != nextChar && '}' != nextChar && ' ' != nextChar && ' ' != nextChar) { fw.write(' '); fillTableChar(fw, bracketCount); } break; case ''': fw.write('''); if(quoteCount == 0) { //When ' is not between "" , change its state. sigleQuoteCount = sigleQuoteCount == 0 ? 1 : 0; } break; case '"': fw.write('"'); if(sigleQuoteCount == 0) { //When ' is not betwe en "", change its state. quoteCount = quoteCount == 0 ? 1 :0; } break; case 'f': // 1. add before "function" if(nextChar == 'u' && lastChar != '=') { // TODO This is a very weak way to determine whether this coming word is "f unction", so it is need to be fixed. fw.write(' '); fw.write(' '); } fw.write('f'); break; default: fw.write(thisChar); break; } if(isAlpha(thisChar)) { if(!isAlpha(lastChar)) { lastWord = ""; } lastWord += String.valueOf(thisChar); } else { if(isAlpha(lastChar)) { if("102111114".equals(lastWord)) { // "for" forCount = 2; } //TODO Whether is is suitable here to determine "function" and add " " before it? } else { lastWord = String.valueOf(thisChar); } } lastChar = thisChar; thisChar = nextChar; if(thisChar != -1) { nextChar = fr.read(); } } // close the files fw.close(); fr.close(); } /** * Find all JS files in the specified directory. * * @param directory The directory in which the files to be Liste d. * @return list The JS file list. */ private static List getJsFileList(String directory) { List jsFileList = new ArrayList(); list(directory, jsFileList); return jsFileList; } /** * List all the JS files in the specified directory recursively. * * @param path The path to be recursively searched for JS files. * @param result The path and file list */ private static void list(String path, List result) { File f = new File(path); if(f.isDirectory()) { File[] fileList = f.listFiles(); for(int i = 0; i < fileList.length; i++) { List(filelist[i].getPath(), result); } } else { if(isJsFile(f.getName())) { result.add(f.getPath()); } } } /** * Determine whether the the specified file is a JS file. * * @param fileName * @return True: is a JS file; False: not a JS file. */ private static boolean isJsFile(String fileName) { //TODO use pattern!!! return ".js".equals(fileName.substring(fileName.length() - 3 )); } /** * List all JS files in the specified directory(Not in their sub -directory). * * @param dir The specified directory. * @return String[] The JS file list. */ private static String[] getSingleDirJsFileList(final String dir) { String[] jsFileList; File path = new File(dir); jsFileList = path.list(new FilenameFilter() { private Pattern pattern = Pattern.compile(".js"); public boolean accept(File dir, String name) { return pattern.matcher(new File(name).getName()).mat ches(); } }); return jsFileList; } /** * Check whether the character is an alpha char. * Actually, the words exist in a function name would no t be limit among those we List below. * This need to be fixed. * * @param c The char to be checked. * @return boolean True: is alpha char; False: is not alpha char. */ private static boolean isAlpha(int c) { return ((c > 'a' && c < 'z') || (c > 'A' && c < 'Z') || (c > '0' && c < '9')); } /** * Fill specified number of ' ' * * @param fw FileWriter * @param charNum Specified number of ' ' * @throws IOException Exception when writing file */ private static void fillTableChar(FileWriter fw, int charNum) th rows IOException { for(int i = 0; i < charNum; i++) { fw.write(' '); } } }