小编Sah*_*ave的帖子

我刚刚使用Ruby 1.9.3p0安装了Rails 3.2.1

davesahil@sahil-pc:~$ gem list rails

*** LOCAL GEMS ***

rails (3.2.1)

$rails --version 给了我这个

/home/davesahil/.rvm/rubies/ruby-1.9.3-p0/lib/ruby/site_ruby/1.9.1/rubygems.rb:314:in `bin_path': can't find gem rails ([">= 0"]) with executable rails (Gem::GemNotFoundException)
    from /home/davesahil/.rvm/gems/ruby-1.9.3-p0/bin/rails:19:in `<main>'

自从我上次在铁轨上工作以来已经有一段时间了.我在这里错过了一些东西吗？

我正在尝试检查jsp中的请求属性以显示/隐藏某些html.

request.setAttribute("submitted", "true");

JSP:

<c:if test="${submitted == 'false'}">
  // some html
</c:if>

但无论我在属性中设置什么值,条件总是计算为false.属性在条件中是不可见的吗？

萨赫勒

我正在尝试使用磁贴集成创建一个简单的Spring 3 MVC应用程序.

当我尝试构建应用程序时,我收到此错误消息(为简洁而截断):

java.lang.NullPointerException
at org.apache.commons.digester.Digester.getXMLReader(Digester.java:1058)
at org.apache.commons.digester.Digester.parse(Digester.java:1887)
at org.apache.tiles.definition.digester.DigesterDefinitionsReader.read(DigesterDefinitionsReader.java:329)
at org.apache.tiles.definition.dao.BaseLocaleUrlDefinitionDAO.loadDefinitionsFromURL(BaseLocaleUrlDefinitionDAO.java:276)
at org.apache.tiles.definition.dao.CachingLocaleUrlDefinitionDAO.loadDefinitionsFromURLs(CachingLocaleUrlDefinitionDAO.java:251)

我错过了一些必需的图书馆吗？

我在WEB-INF/lib文件夹中有以下jar.

commons-beanutils-1.8.0.jar
commons-digester-2.0.jar

org.springframework.asm-3.1.1.RELEASE.jar
org.springframework.beans-3.1.1.RELEASE.jar
org.springframework.context-3.1.1.RELEASE.jar
org.springframework.core-3.1.1.RELEASE.jar
org.springframework.expression-3.1.1.RELEASE.jar
org.springframework.web.servlet-3.1.1.RELEASE.jar
org.springframework.web-3.1.1.RELEASE.jar
tiles-api-2.2.2.jar
tiles-core-2.2.2.jar
tiles-jsp-2.2.2.jar
tiles-servlet-2.2.2.jar
tiles-template-2.2.2.jar
log4j-1.2.16.jar
slf4j-api-1.6.4.jar
slf4j-log4j12-1.6.4.jar

WEB-INF/web.xml文件

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"     xmlns="http://java.sun.com/xml/ns/javaee" xmlns:web="http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" id="WebApp_ID" version="2.5">
<display-name>SpringMVC</display-name>
  <servlet>
<servlet-name>spring</servlet-name>  
<servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
<load-on-startup>1</load-on-startup>  
</servlet>

<servlet-mapping>  
<servlet-name>spring</servlet-name>  
<url-pattern>*.html</url-pattern>
</servlet-mapping>

<welcome-file-list>
<welcome-file>index.jsp</welcome-file>
</welcome-file-list>
</web-app>

WEB-INF /弹簧servlet.xml中

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:mvc="http://www.springframework.org/schema/mvc"
xmlns:context="http://www.springframework.org/schema/context"
xsi:schemaLocation="
    http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-3.0.xsd
    http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
    http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.0.xsd">

<!-- DispatcherServlet Context: …