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Created by Dr. Xi on March 21, 2013 20:29:14
Last update: March 22, 2013 08:58:08
Spring-WS documentation says you can use a Jaxb object as parameter or return type, provided that it is annotated with javax.xml.bind.annotation.XmlRootElement , or is an instance of javax.xml.bind.JAXBElement . But that's a lot easier said than done! For example, if sayHelloResponse is defined as:
<xs:element name="sayHelloResponse" type="tns:sayH... then the JAXB generated class is not annotated with XmlRootElement , therefore, unusable for Spring-WS. You have to define the type as: <xs:element name="sayHelloResponse"> <xs:compl... in order to generate a type annotated with XmlRootElement . But that is not always possible. Alternatively, you can use the Maven plugin maven-jaxb2-plugin with the jaxb2-basics-annotate plugin (yes, plugin inside plugin) to inject the XmlRootElement annotation into the generated JAXB class. This is the pom: <project xmlns="http://maven.apache.org/POM/4.0.0"... and the binding file: <?xml version="1.0" encoding="UTF-8" standalone="y......
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 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 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...
Created by mak on March 04, 2011 14:17:32
Last update: March 04, 2011 14:18:35
To create a zipfile in python:
Code:
#!/usr/local/bin/python
import zipfile
#...
Test
unzip -l test.zip
Archive: test.zip
Lengt...
To read a zipfile in python:
Code:
#!/usr/local/bin/python
import zipfile
#...
Created by voodoo on November 01, 2010 22:26:00
Last update: November 01, 2010 22:26:00
Some weirdness observed while updating BLOB with PostgreSQL JDBC driver: LOB position offset starts at 1 (not 0 as in IO input stream). When you call setBinaryStream(long pos) , pos must be greater than 0. I think this is JDBC standard behavior. When you write to a BLOB output stream, new contents overwrite existing contents. Old contents are not automatically truncated. If new content length is shorter than old contents, the old contents will remain after the position where new content ended. You can call Blob.truncate(long len) to truncate existing contents. However , there seems to be an discrepancy between the JDBC doc and PostgreSQL JDBC driver. The JDBC JavaDoc states that: Truncates the BLOB value that this Blob object represents to be len bytes...
Created by Dr. Xi on September 17, 2010 21:29:47
Last update: September 17, 2010 21:31:43
With JBoss (Tomcat?), the servlet container always appends the default charset ISO-8859-1 to the Content-Type header of a JSP response. For example, if you are using JSP to render PDF and put the following declaration at the top of the JSP:
<%@ page contentType="application/pdf"%> These would be the headers in the HTTP response (notice that charset=ISO-8859-1 was appended to Content-Type ): HTTP/1.1 200 OK Server: Apache-Coyote/1.1 X-... And the output would be truncated a few bytes before non-ASCII characters were encountered, without any error messages ! Maybe you don't intend to output binary files with JSP, but still your response would be truncated without warning if the page happens to contain any non-ASCII characters (when the charset is the default charset=ISO-8859-1 ). However, if you...
Created by Fang on August 23, 2010 22:55:58
Last update: August 24, 2010 15:45:04
The tags XML flow control tags are exactly the same as their Core flow control equivalents, except that the test condition with a boolean EL expression is replaced by the select condition with an XPath expression. In the case of the forEach tag, the items attribute is replaced with the select attribute. In a test condition, the XPath expression is evaluated to a boolean value by the rules of the XPath boolean() function, which converts its argument to a boolean as follows: a number is true if and only if it is neither positive or negative zero nor NaN. a node-set is true if and only if it is non-empty. a string is true if and only if its length is non-zero. an object of...
Created by Fang on July 26, 2010 19:18:28
Last update: August 18, 2010 19:13:02
The tags <c:import> The <c:import> tag imports the contents of a URL and expose that in one of three ways: Import contents from a URL and write it out to the page (url may be relative or absolute):
<c:import url="theUrl" /> Import contents from a URL and save it to a scoped variable string named by the var attribute. Use the scope attribute to define the scope of the exported variable. <c:import url="theUrl" var="importTest" scope="ses... Import a URL and expose to a Reader object named by the varReader attribute. The scope attribute does not apply. The varReader scoped variable can only be accessed within the body of <c:import> . <c:import url="theUrl" varReader="theReader"/> <c:url> The <c:url> tag constructs a URL and writes it out to the...
