http://wendal.net/266.html 使用了v5兽的的代码 判断并移除UTF-8的BOM头

RemoveFileUTF8BOM.java

package net.chinaedu.projects;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.PushbackInputStream;
/**
 * 判断并移除UTF-8的BOM头
 * @author houpo@chinaedu.net
 *
 */
public class RemoveFileUTF8BOM {
    
    /**
     * @param args
     */
    public static void main(String[] args) {
        String path = "E:\\work\\projects\\g3\\G3\\code\\trunk\\venuskeeper";
        File file = new File(path);
        removeDir(file);
    }
    
    public static void removeDir(File file) {
        if (file.isFile() && file.getName().endsWith(".java")) {
            removeFileBom(file);
        } else if (file.isDirectory()) {
            File[] files = file.listFiles();
            for (File file2 : files) {
                removeDir(file2);
            }
        }
    }
    
    public static void removeFileBom(File file) {
        try {
            String path = file.getCanonicalPath();
            InputStream in = utf8filte(new FileInputStream(file));
            File tmpFile = File.createTempFile("utf8", ".tmp");
            FileOutputStream out = new FileOutputStream(tmpFile);
            byte[] buffer = new byte[2048];
            int count = 0;
            while ((count = in.read(buffer)) > 0) {
                out.write(buffer, 0, count);
            }
            in.close();
            out.close();
            file.delete();
            in = new FileInputStream(tmpFile);
            out = new FileOutputStream(path);
            while ((count = in.read(buffer)) > 0) {
                out.write(buffer, 0, count);
            }
            in.close();
            out.close();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
    
    private static final byte[] UTF_BOM = new byte[] { (byte) 0xEF, (byte) 0xBB,
            (byte) 0xBF                };
    
    /**
     * 判断并移除UTF-8的BOM头
     */
    public static InputStream utf8filte(InputStream in) {
        try {
            PushbackInputStream pis = new PushbackInputStream(in, 3);
            byte[] header = new byte[3];
            pis.read(header, 0, 3);
            if (header[0] != UTF_BOM[0] || header[1] != UTF_BOM[1]
                    || header[2] != UTF_BOM[2]) {
                pis.unread(header, 0, 3);
            }
            return pis;
        } catch (IOException e) {
            
        }
        return in;
    }
    
}