javamail附件中文乱码:
/*
        @从BodyPart中提取使用ISO-8859-1编吗的文件名
        @因为BodyPart.getFilename()过程已经对文件名作了一次编码,有时不能直接使用
    */
    public static String getISOFileName(Part body){
        //设置一个标志,判断文件名从Content-Disposition中获取还是从Content-Type中获取
        boolean flag=true;
        if(body==null){
            return null;
        }
        String[] cdis;
        try{
            cdis=body.getHeader("Content-Disposition");
        }
        catch(Exception e){
            return null;
        }
        if(cdis==null){
            flag=false;
        }
        if(!flag){
            try{
                cdis=body.getHeader("Content-Type");
            }
            catch(Exception e){
                return null;
            }
        }
        if(cdis==null){
            return null;
        }
        if(cdis[0]==null){
            return null;
        }
        //从Content-Disposition中获取文件名
        if(flag){
            int pos=cdis[0].indexOf("filename=");
            if(pos<0){
                return null;
            }
            //如果文件名带引号
            if(cdis[0].charAt(cdis[0].length()-1)=='"'){
                return cdis[0].substring(pos+10,cdis[0].length()-1);
            }
            return cdis[0].substring(pos+9,cdis[0].length());
        }
        else{
            int pos=cdis[0].indexOf("name=");
            if(pos<0){
                return null;
            }
            //如果文件名带引号
            if(cdis[0].charAt(cdis[0].length()-1)=='"'){
                return cdis[0].substring(pos+6,cdis[0].length()-1);
            }
            return cdis[0].substring(pos+5,cdis[0].length());
        }
    }