Recent Notes
Displaying keyword search results 1 - 10
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 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 Dr. Xi on February 13, 2012 20:48:56
Last update: February 13, 2012 20:48:56
When you insert an attribute in JSP:
<%@ taglib uri="http://tiles.apache.org/tags-tiles...
you must define the attribute in tiles definitions:
<definition name="/home" template="/WEB-INF/templa...
Otherwise you'll get runtime exception.
The ignore attribute, which defaults to false , will suppress the runtime exception when the attribute is not defined in tiles definition:
<%@ taglib uri="http://tiles.apache.org/tags-tiles...
Created by Fang on February 10, 2012 16:17:13
Last update: February 10, 2012 16:17:13
The annotation @org.hibernate.annotations.Type overrides the default hibernate mapping type used for a column. This can usually be omitted since Hibernate normaly infers the correct type to use.
But @Type is required in ambiguous scenarios such as a java.util.Date attribute, which can map to SQL DATE , TIME or TIMESTAMP . You use the @Type("timestamp") annotation to tell Hibernate that a timestamp converter should be used, which identifies an instance of org.hibernate.type.TimestampType .
@Type can also be used to identify custom type converters, which can be defined with @TypeDef at the class level:
@TypeDefs(
{
@TypeDef(
na...
or with an xml file:
<?xml version="1.0"?>
<!DOCTYPE hibernate-mappi...
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 zhidao on January 25, 2012 16:07:29
Last update: January 25, 2012 16:07:29
A JSON response is auto-magically returned when you add the @ResponseBody annotation to the return value of a @RequestMapping annotated method:
import org.springframework.stereotype.Controller;
...
For magic to happen, you must:
Add annotation-driven to the org.springframework.web.servlet.DispatcherServlet config xml:
<?xml version="1.0" encoding="UTF-8"?>
<beans x...
Put Jackson jar files on CLASSPATH (i.e., under WEB-INF/lib ), which includes jackson-core-asl-1.6.4.jar and jackson-mapper-asl-1.6.4.jar .
Created by Fang on December 06, 2011 19:03:25
Last update: December 07, 2011 08:54:11
Our custom tag, as implemented in the previous note , is broken when a template is used.
Create a template file ( home-template.xhtml ):
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Stric...
and a test page that uses it ( home.xhtml ):
<?xml version="1.0" encoding="UTF-8"?>
<ui:comp...
Then request the page with URL: http://localhost:8080/facelet-demo/home.jsf?name=Jack .
You'll find that our hello tag works inside ui:repeat but fails to get the value defined by ui:param ! What's the problem? Our hello tag implementation evaluated the EL with the wrong EL context!
This is the corrected implementation:
package com.example;
import java.io.IOExcep...
Created by Fang on November 10, 2011 13:19:13
Last update: December 01, 2011 19:10:43
You can add custom implicit variables to JSF pages by using a custom EL resolver, in two simple steps: Write an ELResolver class to resolve the variable Add the ELResolver to faces-config.xml Starting from the Maven Hello World example: Add faces API and EL dependencies to pom.xml :
<dependencies> <dependency> <groupId>o... Add a simple greeter class ( src/main/java/com/example/Greeter.java ): package com.example; public class Greeter {... Add our custom EL resolver ( src/main/java/com/example/ELResolver.java ): package com.example; import java.util.Itera... Add the custom EL resolver to src/main/resources/META-INF/faces-config.xml <?xml version="1.0" encoding="UTF-8"?> <faces-c... Build JAR with mvn package Drop the JAR into WEB-INF/lib of a webapp and test the new EL with: <h:outputText value="#{Greeter.sayHi('Mike')}"/> Fixed: the setValue method used to throw an exception, which is wrong. @Override public void setValue(ELContext ctx, O......
Created by nogeek on November 27, 2011 12:24:27
Last update: November 27, 2011 12:24:27
There is no XSLT 2.0 support in the JDK as of 7.0. According to Stackoverflow , there are three Java packages that support XSLT 2.0: Saxon IBM WebSphere XML Feature Pack Oracle XDK There are no known support for XSLT in browsers. According to Wikipedia : XSLT is developed by the World Wide Web Consortium (W3C). The most recent version is XSLT 2.0, which reached W3C recommendation status on 23 January 2007. As of 2010, however, XSLT 1.0 is still widely used, as there are no products that support XSLT 2.0 running in the browser, nor on some important server environments such as LAMP. Expressions like this:
format-date(xs:date('1999-12-31'), '[D01] [MNn] ... where format-date is a XSLT 2.0 function and date is a XPath 2.0 constructor...
Created by Fang on November 21, 2011 15:57:49
Last update: November 22, 2011 09:51:26
The improved custom taglib works with existing facelet ui taglibs. For example:
<ui:param name="theName" value="John"/> <my:hel... produces the expected output. However, a problem exists with the ui:repeat tag: <h3>With ui:repeat</h3> <ui:repeat var="theName... When tested with a URL like: http://localhost:8080/facelet-demo/?name=Zack&name... the raw EL prints out the correct names, but my custom tag substitutes empty string for theName2 ! In theory, the response is rendered in the Render Response phase, way after the Apply Request Values phase, actual values should be available to EL. The answer to this anomaly turned out to be very deep ! Yes, right there in the code! I would consider this a bug in facelets implementation, but the JSF spec did not tell what the expected behavior should be. In my custom...
