BOMRemover v2.0 去除代码中的UTF-8 BOM

org.xml.sax.SAXParseException: 缺少文件根组件。但是XML文件确实存在且格式正常.

原因: XML文件可能为UTF-8编码....且带有BOM签名..用UltraEdit等16进制工具打开XML,可看到前三字节为EF,BB,BF.



解决方法..找到此XML文件,删除BOM签名...



见我的 BOM批量删除工具 BOMRemoverV2.0



此工具来源于BOMRemover 在此基础上完美了下方法...主要增加了 noBomFile方法 ,以检测文件是否为BOM签名文件.



使用方法:

1.trimBom 去掉单个文件的BOM头

2.DealSrcFiles 去掉某个文件夹下的文件BOM头...

import java.io.BufferedReader;
import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.FileReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.PushbackInputStream;
import java.util.ArrayList;
import java.util.HashSet;
import java.util.Iterator;
import java.util.List;
import java.util.Set;

public class BOMRemover {

	/**
	 * ant 编译之后的result文件，注意要编译提示错误的文件名要在同一行 可以设置命令提示窗口的缓冲区大小实现
	 * 
	 * @param resultFileName
	 */
	public static Set getFileNamesFromCompileResult(String resultFileName)
			throws java.io.IOException {
		Set set = new HashSet();
		BufferedReader reader = new BufferedReader(new FileReader(
				resultFileName));
		String start = "[javac] ";
		int startLen = start.length();
		String end = ".java:";
		int endLen = end.length();

		String errMsg = "//65279";
		while (reader.ready()) {
			String line = reader.readLine();
			int indexStart = line.indexOf(start);

			if (line.indexOf(errMsg) == -1) {
				continue;
			}
			if (indexStart != -1) {
				int indexEnd = line.indexOf(end);
				if (indexEnd != -1) {
					String name = line.substring(indexStart + startLen,
							indexEnd + endLen - 1);
					set.add(name.trim());
				}
			}
		}
		return set;

	}

	
	//trim dir
	public static void DealSrcFiles(String path) {
		if (path.charAt(path.length() - 1) != '//') {
			path += '//';
		}
		File file = new File(path);
		if (!file.exists()) {
			System.out.println("Error: Path not Existed! Please Check it out!");
			return;
		}
		String[] filelist = file.list();
		for (int i = 0; i < filelist.length; i++) {
			File temp = new File(path + filelist[i]);
			if ((temp.isDirectory() && !temp.isHidden() && temp.exists())) {
				DealSrcFiles(path + filelist[i]);
			} else {
				if (filelist[i].endsWith(".xml")) {
					try {
						// System.out.println(path + filelist[i]);
						trimBom(path + filelist[i]);
					} catch (Exception eee) {
						System.out.println(eee.getMessage());
					}
				}
			}
		}
	}

	/**
	 * 读取流中前面的字符，看是否有bom，如果有bom，将bom头先读掉丢弃
	 * 
	 * @param in
	 * @return
	 * @throws IOException
	 */
	public static InputStream getInputStream(InputStream in) throws IOException {

		PushbackInputStream testin = new PushbackInputStream(in);
		int ch = testin.read();
		if (ch != 0xEF) {
			testin.unread(ch);
		} else if ((ch = testin.read()) != 0xBB) { // if ch==0xef
			testin.unread(ch);
			testin.unread(0xef);
		} else if ((ch = testin.read()) != 0xBF) { // if ch ==0xbb
			throw new IOException("错误的UTF-8格式文件");
		} else { // if ch ==0xbf
			// 不需要做，这里是bom头被读完了
			// // System.out.println("still exist bom");

		}
		return testin;

	}

	/**
	 * 根据一个文件名，读取完文件，干掉bom头。
	 * 
	 * @param fileName
	 * @throws IOException
	 */
	public static void trimBom(String fileName) throws IOException {

	

		if (noBomFile(fileName)) {
			System.out.println("skip :" + fileName);
			return;
		}
		
		
		
		FileInputStream fin = new FileInputStream(fileName);
		// 开始写临时文件
		InputStream in = getInputStream(fin);
		ByteArrayOutputStream bos = new ByteArrayOutputStream();
		byte b[] = new byte[4096];

		int len = 0;
		while (in.available() > 0) {
			len = in.read(b, 0, 4096);
			// out.write(b, 0, len);
			bos.write(b, 0, len);
		}

		in.close();
		fin.close();
		bos.close();

		// 临时文件写完，开始将临时文件写回本文件。
	 	System.out.println("[" + fileName + "]");
		FileOutputStream out = new FileOutputStream(fileName);
		out.write(bos.toByteArray());
		out.close();
		System.out.println("PROCESS FILE " + fileName);
	}

	// check the file is or not bom file
	private static boolean noBomFile(String  fname) throws IOException {
		FileInputStream fin = new FileInputStream(fname);
		PushbackInputStream testin = new PushbackInputStream(fin);
		int ch = testin.read();
		int ch2 = testin.read();
		int ch3 = testin.read();

		if (ch == 0xEF && ch2 == 0xBB && ch3 == 0xBF) {
		 
			return false; // is bom file
		} else {
		 
			return true;
		}
	}

	/**
	 * 根据ant编译错误来去除bom
	 * 
	 * @param resultFile
	 * @throws IOException
	 */
	// public static void trimBomByCompileResult(String resultFile)
	// throws IOException {
	// Set set = getFileNamesFromCompileResult(resultFile);
	//
	// for (Iterator it = set.iterator(); it.hasNext();) {
	// String fName = it.next().toString();
	// trimBom(fName);
	// }
	//
	// }

	public static void main(String[] args) throws IOException {
		// if(args.length==0){
		// DealSrcFiles(System.getProperty("user.dir"));
		// }
		// else{
		// DealSrcFiles(args[0]);
		// }
		String path = "D://Documents and Settings//Administrator//桌面//0301//de bom xml";
		DealSrcFiles(path);
	}
}

原工具来源于 http://hi.baidu.com/joyfun/blog/item/ca926f06c40cc0710308815b.html

去除java代码中的UTF-8 BOM