启用JSP Custom taglib以使用spring服务bean [英] Enable JSP Custom taglib to use spring service beans

问题描述

我正在开发一个使用Spring MVC 3.2.4（Spring Core 3.2.4）和jpa& hibernate用于后端。目前正在使用Tomcat v6.0进行测试。

I'm developing a web application using Spring MVC 3.2.4 (Spring Core 3.2.4 too) with jpa & hibernate for the back-end. And currently using Tomcat v6.0 for testing.

我有一个案例，我创建了一个JSP自定义标记库lib（使用jsp-api 2.1.1& servlet-api 2.5），这是一个自定义查找下拉列表列表，我会给它查找类型，它将从DB获取此类型下的项目呈现为列表中的项目。

I had a case when i created a JSP custom tag lib (using jsp-api 2.1.1 & servlet-api 2.5), which is a custom lookups drop down list, i would give it the lookup type, and it would get from the DB the items under this type to render as items in the list.

自定义taglib类基本上看起来像这样：

The custom taglib class basically looks like something similar to this:

public class LookupsTag extends SimpleTagSupport {
  @Autowired
  private static LookupService lookupService;
  private String type;

    public void doTag() throws JspException, IOException {
        List<Lookup> items = lookupService.findByType(getType());

        StringBuffer buff = new StringBuffer();
        buff.append("<select>");
        //...adding items...
        buff.append("</select>");
        getJspContext().getOut().write(buff.toString());
    }
  //getters and setters
}

和我已经相应地创建了tld文件。

And i have created the tld file accordingly and all.

一旦我尝试使用此自定义标记查看页面，就会抛出 NullPointerException ，因为在 doTag（）方法， lookupService 实例是 null 。

Once i attempt to view a page using this custom tag, a NullPointerException is thrown because inside the doTag() method, the lookupService instance is null.

Spring似乎不支持自定义jsp标记。有没有办法解决这个问题，使服务实例自动自动装配？或者我错过了一些弹簧配置吗？

Spring doesn't seem to support custom jsp tags. Is there a way to work around this to make the service instance autowired automatically? Or am i missing some spring configurations to do?

谢谢，

推荐答案

<感谢Alan Hay的评论，不支持自定义jsp taglib。
Spring已经通过他们的taglib提供了我需要的东西 http://docs.spring.io/spring/docs/current/spring-framework-reference/html/spring-form.tld.html#spring-form .tld.select

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