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Created by zhidao on April 25, 2012 14:56:38
Last update: April 25, 2012 14:56:38
Lacking better alternatives, this is how I render a global validation error:
<spring:bind path="changePasswordForm">
<c:if ...
<form:errors> without path attribute seems to work too:
<form:errors cssClass="ui-error"/>
Created by Dr. Xi on April 19, 2012 10:10:08
Last update: April 19, 2012 10:11:06
The default servlet for Tomcat is declared in $CATALINA_HOME/conf/web.xml :
<servlet>
<servlet-name>default</servle...
Therefore, static content is rendered by the default configuration unless you override it with your own definitions.
If you want to allow directory listing, just change the listing parameter to true :
<init-param>
<param-name>listings</para...
Change the welcome-file-list to display a default page in lieu of a directory listing:
<welcome-file-list>
<welcome-file>home.xhtml</...
Welcome pages are defined at the Web application level.
Created by Fang on April 16, 2012 13:18:40
Last update: April 16, 2012 13:18:40
Simply call pageContext.setAttribute() to export a variable from within a JSP custom tag:
public class MyCustomVarTag extends TagSupport {
...
The availability of the exported variable can be limited in the TLD:
<tag>
<name>setVar</name>
<tag-class...
The availability scopes are:
Value Availability
NESTED Between the start tag and the end tag.
AT_BEGIN From the start tag until the scope of any enclosing tag. If there’s no enclosing tag, then to the end of the page.
AT_END After the end tag until the scope of any enclosing tag. If there’s no enclosing tag, then to the end of the page.
Created by Fang on April 16, 2012 12:58:35
Last update: April 16, 2012 12:58:35
To implement a JSP custom tag with dynamic attributes (for example, to pass-thru arbitrary attributes not handled by the JSP tag):
Set the dynamic-attributes element to true in the TLD:
<tag>
<name>mark</name>
<tag-class>c...
The tag handler must implement javax.servlet.jsp.tagext.DynamicAttributes :
package com.example.jsp;
import java.io.*;
...
Created by Fang on March 30, 2012 15:04:04
Last update: March 30, 2012 15:04:04
Spring MVC 3.1 can send either JSON or HTML response on the same URL, depending on the type of response requested. With this mechanism, a page can be sent when directly requested from a link, but a JSON response can be sent in response to an AJAX request. This is the controller code:
package com.example; import java.util.Map; ... In the above example, JSON response will be sent when the HTTP request contains header "Accept: application/json". HTML response will be sent then the header is "Accept: */*", or "Accept: text/html", or anything else. You can add a limitation that the HTML response does not produce "application/json". But then the question is which response will be sent when the HTTP header is "Accept: */*"? Both methods will...
Created by Fang on March 30, 2012 12:28:47
Last update: March 30, 2012 12:28:47
The HandlerMapping bean for @RequestMapping annotated @Controller is:
org.springframework.web.servlet.mvc.annotation.DefaultAnnotationHandlerMapping for Spring MVC prior to 3.1
org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerMapping for Spring MVC 3.1
This info might be handy if you want to add an interceptor:
<beans>
<bean id="handlerMapping"
...
Created by Fang on March 15, 2012 10:24:35
Last update: March 15, 2012 10:24:35
Suppose that I have an email field annotated with:
@NotEmpty(message="Please enter email address")
...
Bean validation will trigger two errors when no email address is entered:
the email field is empty
an empty email field is not a valid email address
Displaying both errors to the user with <form:errors> would be redundant and confusing:
<%@ taglib uri="http://www.springframework.org/tag...
This is how to display the first error only:
<spring:bind path="emailAddress">
<c:if test="$...
Created by Fang on February 23, 2012 14:25:57
Last update: March 01, 2012 13:53:59
Some example snippets for Spring message configuration and usage.
To configure a message source in Spring context (basename=messages):
<bean id="messageSource"
class="org.springf...
Locale change interceptor can also be setup with:
<?xml version="1.0" encoding="UTF-8"?>
<beans x...
The messages file should be named messages.properties (or messages_en.properties , etc.) and located on CLASSPATH , for example: WEB-INF/classes .
To use a message resource in JSP:
<%@ taglib prefix="spring" uri="http://www.springf...
Created by James on February 02, 2012 16:09:05
Last update: February 02, 2012 16:09:17
flowplayer is another way to embed Flash in a web page. The code looks like this:
<object width="6400" height="380" data="swf/flowpl...
You need to download two swf files:
http://releases.flowplayer.org/swf/flowplayer-3.2.1.swf
http://releases.flowplayer.org/swf/flowplayer.controls-3.2.0.swf
Created by Fang on January 31, 2012 15:40:34
Last update: January 31, 2012 15:41:28
This is a simple Hello World application with Spring 3 MVC. Like the default Apache HTTPd welcome page, it displays " It works! " when successfully deployed. The sole purpose is to show the minimum elements needed to setup Spring 3 MVC.
I use Maven since it's so much easier than downloading the dependencies manually.
Directory layout:
./src
./src/main
./src/main/webapp
./src/...
pom.xml :
<?xml version="1.0" encoding="UTF-8"?>
<project...
WEB-INF/web.xml :
<?xml version="1.0" encoding="UTF-8"?>
<web-app...
WEB-INF/applicationContext.xml (empty, but needed):
<?xml version="1.0" encoding="UTF-8"?>
<beans x...
WEB-INF/spring-servlet.xml :
<?xml version="1.0" encoding="UTF-8"?>
<beans x...
WEB-INF/jsp/home.jsp :
<!DOCTYPE html>
<html>
<head>
<title>H...
Build with:
mvn clean package
The resulting webapp is target/springmvc.war .