String food[]=request.getParameterValues("food");

This line of code creates a String array called "food" and assigns it the values of the "food" parameter received from an HTTP request.

For example, if the HTTP request contained a query string parameter called "food" with the values "pizza" and "burger", the "food" array would be created as follows:

String food[] = {"pizza", "burger"};

This allows the developer to access and manipulate the values of the "food" parameter in their Java code.

相关问题

<% String name=request.getParameter("name"); name=new String(name.getBytes("iso-8859-1"),"UTF-8"); session.setAttribute("name",name); String sex=request.getParameter("gender"); String[] hobby=request.getParameterValues("hobby"); String mes=""; if(name.equals("")){ mes="昵称不能为空，请输入昵称"; mes = URLEncoder.encode(mes); session.setAttribute("mes",mes); RequestDispatcher rd = request.getRequestDispatcher("input.jsp"); rd.forward(request,response); } else{ RequestDispatcher rd = request.getRequestDispatcher("infromation.jsp"); rd.forward(request,response); } session.setAttribute("sex",sex); session.setAttribute("hobby",hobby); %>哪里错了

这段代码中可能会出现一些问题，具体如下：

1. 在设置 name 属性时，应该先进行非空判断，否则可能会出现空指针异常。

2. 在进行转码时，应该使用 try-catch 块进行异常处理。

3. 在设置完 name 属性后，应该立即跳转到相应的页面，否则可能会出现逻辑错误。

建议修改后的代码如下：

<%
    String name = request.getParameter("name");
    String sex = request.getParameter("gender");
    String[] hobby = request.getParameterValues("hobby");
    String mes = "";

    if (name == null || name.equals("")) {
        mes = "昵称不能为空，请输入昵称";
        mes = URLEncoder.encode(mes, "UTF-8");
        session.setAttribute("mes", mes);
        RequestDispatcher rd = request.getRequestDispatcher("input.jsp");
        rd.forward(request, response);
    } else {
        name = new String(name.getBytes("ISO-8859-1"), "UTF-8");
        session.setAttribute("name", name);
        session.setAttribute("sex", sex);
        session.setAttribute("hobby", hobby);
        RequestDispatcher rd = request.getRequestDispatcher("information.jsp");
        rd.forward(request, response);
    }
%>

public void save() { String title = request.getParameter("title"); String pubren = request.getParameter("pubren"); String pubtime = request.getParameter("pubtime"); String laiyuan=request.getParameter("laiyuan"); String dcontent = request.getParameter("dcontent"); String tupian2 = request.getParameter("tupian2"); String lanmuid = request.getParameter("lanmuid"); String lanmuming = request.getParameter("lanmuming"); String tuijian=request.getParameter("tuijian"); String hot=request.getParameter("hot"); String zuixin=request.getParameter("zuixin"); String zhaiyao=request.getParameter("zhaiyao"); String style=request.getParameter("style"); SimpleDateFormat sdfxinxi = new SimpleDateFormat("yyyy-MM-dd"); Xinxi xinxi = new Xinxi(); xinxi.setTitle(title == null ? "" : title); xinxi.setPubren(pubren == null ? "" : pubren); xinxi.setPubtime(new Date()); xinxi.setHot(hot!=null?1:0); xinxi.setTuijian(tuijian!=null?1:0); xinxi.setZuixin(zuixin!=null?1:0); xinxi.setClickcount(0); xinxi.setZhaiyao(zhaiyao==null?"":zhaiyao); xinxi.setDcontent(dcontent == null ? "" : dcontent); xinxi.setTupian2(tupian2 == null ? "" : tupian2); xinxi.setAgainstcount(0); xinxi.setAgreecount(0); xinxi.setLanmuid(new Integer(lanmuid)); xinxi.setLanmuming(lanmuming == null ? "" : lanmuming); DALBase.save(xinxi); try { if(style!=null&&style.equals("admin")) response.sendRedirect("xinximanager.do?actiontype=get&seedid=201&lanmuid="+xinxi.getLanmuid()); if(style!=null&&style.equals("huiyuan")) response.sendRedirect("../e/myxinximanager.jsp?seedid=m2"); } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } } /****************************************************** *********************** 内部附件支持********************* ***public void attachements(HttpServletRequest request, HttpServletResponse response, String belongid) { DALBase.delete("attachement", MessageFormat.format( " where belongid=''{0}'' and belongtable=''xinxi'' ", belongid)); String[] photos = request.getParameterValues("fileuploaded"); if (photos == null) return; for (int i = 0; i < photos.length; i++) { Attachement a = new Attachement(); a.setType("images"); a.setPubtime(new Date()); a.setBelongfileldname("id"); a.setFilename(photos[i]); a.setBelongid(belongid); a.setBelongtable("xinxi"); a.setUrl(SystemParam.getSiteRoot() + "/upload/temp/" + a.getFilename()); a.setTitle(a.getFilename()); DALBase.save(a); } }解释每一行代码

这是一段Java代码，根据传入的HTTP请求参数保存一个信息（Xinxi）到数据库中。下面是每行代码的解释：

public void save() { // 定义一个公有方法save()
    // 从请求参数中获取信息标题、发布者、发布时间、来源、正文内容、图片、栏目ID、栏目名称、推荐、热点和最新等信息
    String title = request.getParameter("title");
    String pubren = request.getParameter("pubren");
    String pubtime = request.getParameter("pubtime");
    String laiyuan=request.getParameter("laiyuan");
    String dcontent = request.getParameter("dcontent");
    String tupian2 = request.getParameter("tupian2");
    String lanmuid = request.getParameter("lanmuid");
    String lanmuming = request.getParameter("lanmuming");
    String  tuijian=request.getParameter("tuijian");
    String  hot=request.getParameter("hot");
    String zuixin=request.getParameter("zuixin");
    String  zhaiyao=request.getParameter("zhaiyao");
    String style=request.getParameter("style");
    // 定义一个日期格式化对象，格式为"yyyy-MM-dd"
    SimpleDateFormat sdfxinxi = new SimpleDateFormat("yyyy-MM-dd");
    // 创建一个信息对象
    Xinxi xinxi = new Xinxi();
    // 将获取到的信息设置到信息对象中
    xinxi.setTitle(title == null ? "" : title);
    xinxi.setPubren(pubren == null ? "" : pubren);
    xinxi.setPubtime(new Date()); // 设置发布时间为当前时间
    xinxi.setHot(hot!=null?1:0); // 如果参数hot不为空，则将热点属性设为1，否则设为0
    xinxi.setTuijian(tuijian!=null?1:0); // 如果参数tuijian不为空，则将推荐属性设为1，否则设为0
    xinxi.setZuixin(zuixin!=null?1:0); // 如果参数zuixin不为空，则将最新属性设为1，否则设为0
    xinxi.setClickcount(0); // 设置点击次数为0
    xinxi.setZhaiyao(zhaiyao==null?"":zhaiyao);
    xinxi.setDcontent(dcontent == null ? "" : dcontent);
    xinxi.setTupian2(tupian2 == null ? "" : tupian2);
    xinxi.setAgainstcount(0); // 设置反对次数为0
    xinxi.setAgreecount(0); // 设置赞同次数为0
    xinxi.setLanmuid(new Integer(lanmuid)); // 将栏目ID设置到信息对象中
    xinxi.setLanmuming(lanmuming == null ? "" : lanmuming);
    // 调用数据访问层的save()方法保存信息对象到数据库中
    DALBase.save(xinxi);
    try {
        // 根据请求参数中的style值进行不同的重定向操作
        if(style!=null&&style.equals("admin"))
            response.sendRedirect("xinximanager.do?actiontype=get&seedid=201&lanmuid="+xinxi.getLanmuid());
        if(style!=null&&style.equals("huiyuan"))
            response.sendRedirect("../e/myxinximanager.jsp?seedid=m2");
    } catch (IOException e) {
        e.printStackTrace();
    }
}

// 定义一个公有方法attachements()用于支持内部附件
public void attachements(HttpServletRequest request, HttpServletResponse response, String belongid) {
    // 删除已存在的附件
    DALBase.delete("attachement", MessageFormat.format(" where belongid=''{0}'' and belongtable=''xinxi'' ", belongid));
    // 获取请求参数中的上传的图片文件名
    String[] photos = request.getParameterValues("fileuploaded");
    if (photos == null)
        return;
    // 遍历图片文件名数组，创建附件对象并保存到数据库中
    for (int i = 0; i < photos.length; i++) {
        Attachement a = new Attachement();
        a.setType("images");
        a.setPubtime(new Date()); // 设置附件发布时间为当前时间
        a.setBelongfileldname("id");
        a.setFilename(photos[i]);
        a.setBelongid(belongid);
        a.setBelongtable("xinxi");
        a.setUrl(SystemParam.getSiteRoot() + "/upload/temp/" + a.getFilename());
        a.setTitle(a.getFilename());
        DALBase.save(a);
    }
}