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Created by Fang on April 16, 2012 13:32:10
Last update: April 16, 2012 13:32:10
There are two steps to create a custom function for JSP:
Declare the function in the TLD:
<?xml version="1.0" encoding="UTF-8" ?>
<taglib...
Implement the function (must be static):
package com.example;
public class UrlTransl...
To use the function:
<%@ taglib uri="http://www.example.com/jsp/tags" p...
Created by Fang on February 24, 2012 14:38:06
Last update: April 06, 2012 13:19:29
Step 1: create a Json factory:
package com.my.service.dev;
import java.io....
Step 2: use it:
ObjectMapper mapper = new ObjectMapper(new AllowCo...
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 Dr. Xi on March 13, 2012 08:46:57
Last update: March 13, 2012 08:46:57
This trick sets HTML base to the root context path of the current webapp:
The short version:
<!DOCTYPE html>
<%@ taglib uri="http://java.sun...
The long version:
<!DOCTYPE html>
<%@ taglib uri="http://java.sun...
Created by Fang on March 05, 2012 20:11:56
Last update: March 05, 2012 20:11:56
This is a bare bones Maven project to get started with Java JSR 303 bean validation.
Directory structure:
./pom.xml
./src
./src/main
./src/main/jav...
pom.xml :
<project xmlns="http://maven.apache.org/POM/4.0.0"...
which includes dependencies on JUnit, Java bean validation API and the Hibernate validator reference implementation.
Created by Fang on March 02, 2012 13:23:35
Last update: March 02, 2012 13:23:35
The landing page after login can be configured with the default-target-url attribute of form-login . If a user was redirected to the login form after requesting a restricted URL, she's redirected to the original requested page after successful login.
An easy configuration looks like this:
<beans:beans xmlns="http://www.springframework.org...
But there are times that you want to do more initialization after login (such as loading user data), or apply more complex logic before redirecting. This is where the authentication-success-handler-ref attribute comes into play. You create a class that implements org.springframework.security.web.authentication.AuthenticationSuccessHandler and use that as the authentication-success-handler-ref :
<http
entry-point-ref="authProcessFilterEn...
This is a skeleton implementation:
public class MyAuthenticationSuccessHandler implem...
Created by Fang on February 27, 2012 12:19:19
Last update: February 27, 2012 12:19:19
Mapping Java objects to Jackson JSON is pretty simple. But if you name a JSON field wrong, you'll get the "Unrecognized field ... (Class ...), not marked as ignorable" error. The rule for mapping a Java bean attribute name to a JSON field name is: lower all leading capital letters until the first lower case letter .
For example, this Java class:
package com.example;
public class Person {
...
maps to this JSON string:
{
"firstName": "Jane",
"lastName": "...
Test code:
package com.example;
import java.net.URL;
...
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 .
Created by Fang on January 31, 2012 13:57:56
Last update: January 31, 2012 15:04:29
These are the minimum steps to configure Spring MVC in web.xml :
Bootstrap Spring MVC by registering ContextLoaderListener :
<listener>
<listener-class>
org.springfra...
Register the DispatcherServlet :
<servlet>
<servlet-name>spring</servlet-name>
...
Add servlet-mapping :
<servlet-mapping>
<servlet-name>spring</servle...
Configure DispatcherServlet with WEB-INF/spring-servlet.xml , which configures WebApplicationContext specific to this servlet.
<?xml version="1.0" encoding="UTF-8"?>
<beans x...
Optionally, use context-param in web.xml to configure the global WebApplicationContext :
<!-- XmlWebApplicationContext is the default, so t...
If you omit this section, you have to create file WEB-INF/applicationContext.xml , even if it's empty.
This is the full web.xml :
<?xml version="1.0" encoding="UTF-8"?>
<web-app...
Created by Fang on January 28, 2012 13:24:09
Last update: January 28, 2012 13:31:22
This is a simple JSP custom tags library with tag body. Just like the JSF counterpart , it splits a string and repeats the body for each word, i.e., with this markup:
<%@ taglib uri="http://custom.tag.com/demo" prefix...
output:
<html>
<body>
<p>Hello Tigger!</p>
<p>H...
With Maven, this is the directory structure:
./src
./src/main
./src/main/resources
./s...
There are three files to write:
pom.xml :
<project xmlns="http://maven.apache.org/POM/4.0.0"...
src/main/java/tagdemo/IterateTag.java :
package tagdemo;
import java.io.IOException...
src/main/resources/META-INF/demotag.tld :
<?xml version="1.0" encoding="UTF-8"?>
<!DO...
Build with:
mvn clean install
To use it as a dependency in other Maven projects:
<dependency>
<groupId>tag-demo</groupId>
...
