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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>
...
Created by Fang on November 08, 2011 20:55:00
Last update: November 21, 2011 18:19:44
In the simple taglib example , I used a tag handler class to implement a taglib. This is an example to implement a taglib with a UI component. The purpose is to use a custom tag to split a string and print each part in a separate paragraph, i.e., print
<p>john</p> <p>steve</p> <p>mike</p> with custom tag <my:foreach> : <my:foreach var="who" value="john steve mike"> ... These are the files: pom.xml <project xmlns="http://maven.apache.org/POM/4.0.0"... src/main/java/com/example/UIForeash.java : package com.example; import java.io.IOExcep... src/main/resources/META-INF/faces-config.xml : <?xml version="1.0" encoding="UTF-8"?> <faces-c... src/main/resources/META-INF/foreach.taglib.xml : <?xml version="1.0" encoding="UTF-8"?> <facelet... How to use: Put the JAR file generated by the above project in the WEB-INF/lib folder of the web app. If the web app is a Maven project, just add the taglib project as a dependency:...
Created by Fang on November 21, 2011 13:49:11
Last update: November 21, 2011 13:49:11
In the test for the simple taglib example , I used a literal string for the name attribute:
<my:hello name="Jack"/> What happens if the name attribute contains EL expresson? For example: <my:hello name="#{param['name']}"/> If EL works, the tag should take the value of the " name " request parameter and print it out. But the tag as implemented in the simple taglib example prints the literal string: Hello #{param['name']}! I am FaceletTag. In order to make a tag to recognize EL, we have to use TagAttribute.getValue(FaceletContext ctx) instead of TagAttribute.getValue() . The latter returns the literal value of the attribute. The HelloTagHandler should be changed to: package com.example; import java.io.IOExcep... Rebuild the taglib and test with a URL like this: http://localhost:8080/facelet-test/?name=Jack The tag will print:...
Created by Fang on November 03, 2011 19:47:38
Last update: November 08, 2011 20:24:47
This is a step-by-step example to create a really simple facelet taglib (in JSF 2 with Maven). Create a simple Maven project with:
mvn archetype:create -DgroupId=com.example -Dartif... Three files are created as a result: pom.xml src/main/java/com/example/App.java src/test/java/com/example/AppTest.java This project should be able to build with: mvn package Add facelet API dependencies to pom.xml : <project xmlns="http://maven.apache.org/POM/4.... The compiler plugin section is optional. Remove src/main/java/com/example/App.java , create a new Java class as the facelet Tag Handler ( HelloTagHandler.java ): package com.example; import java.io.IOExcep... This tag handler simply prints a "Hello" message. Create facelet tag declaration file src/main/resources/META-INF/hello.taglib.xml : <?xml version="1.0" encoding="UTF-8"?> <facelet... Build the JAR with mvn clean package Optionally, install it to the local repository: mvn install To use the taglib, simply drop the...
Created by Fang on September 07, 2009 20:44:15
Last update: November 03, 2011 14:43:19
Step 1: Repackage a web app as EAR A Java EE application is a multimodule Maven project. At the very least you'll need to package a WAR and an EAR. To get started, I'll simply re-package the simple webapp as an EAR. Create a directory named javaee-app Copy the webapp from here to javaee-app . Rename struts1app to webapp . Create pom.xml under javaee-app :
<project> <modelVersion>4.0.0</modelVersion>... Create a directory named ear under javaee-app . Create pom.xml under ear : <project> <modelVersion>4.0.0</modelVersion>... Modify pom.xml in the webapp directory so that it looks like this: <project> <modelVersion>4.0.0</modelVersion> ... Build with " mvn package " in the javaee-app directory. You can see that ear-1.0.ear is successfully generated in javaee-app/ear/target . Maven successfully resolves dependencies between the sub-projects....
Created by Dr. Xi on June 22, 2011 07:33:45
Last update: June 22, 2011 11:57:54
Demo code for CSV parsing with OpenCSV . Java code:
import java.io.*; import au.com.bytecode.opencs... Test with a simple CSV file: psmith01,CLASS2B,Peter Smith 1,YEAR2,1,N,ADVANCED,... The parser worked correctly: Line 1 has 11 values: |psmith01| |CLASS2B|... Test with a more complicated CSV file: "psmith01 abc", "CLASS2B " , " Peter... Result: Line 1 has 4 values: |psmith01 abc| |CLASS... The parser: Escaped quote and backslash correctly Ignored spaces before the quotation mark - sometimes (see below) Counted spaces after the right quotation mark till the comma as content, including the right quotation mark (bug). Ignored improperly quoted item - silently (third line) Indeed, the OpenCSV parser has a problem with spaces: Input: "Smith, Jack", "210-345-8888" "Smith, J... Result: Line 1 has 2 values: | Smith, Jack| |210-3......
Created by Dr. Xi on June 22, 2011 09:42:35
Last update: June 22, 2011 11:39:40
Demo code for CSV parsing with Skife CSV . Java code:
import java.io.*; import java.util.*; import... Test with a simple CSV file: psmith01,CLASS2B,Peter Smith 1,YEAR2,1,N,ADVANCED,... The parser worked correctly: Line 1 has 11 values: |psmith01| |CLASS2B|... Test with a more complicated CSV file: "psmith01 abc", "CLASS2B " , " Peter... Result: Line 1 has 4 values: |psmith01 abc| | CLAS... The parser worked correctly. But notice that it counts the spaces outside of the quotes significant, and doing so consistently. One more test for spaces: "Smith, Jack" , "210-345-8888" "Smith, Jack"... Result: Line 1 has 2 values: | Smith, Jack | | 210... Add a new line in item two: "One", "Two ", "Three" Result: Line 1 has 2 values: |One| | Two| L...
Created by Dr. Xi on June 21, 2011 15:41:51
Last update: June 22, 2011 11:33:36
Demo code for CSV parsing with Apache Commons CSV parser .
Java code:
import java.io.*;
import org.apache.commons.csv...
Test with a simple CSV file:
psmith01,CLASS2B,Peter Smith 1,YEAR2,1,N,ADVANCED,...
Result:
Line 1 has 11 values:
|psmith01|
|CLASS2B|...
The parser worked correctly.
Test with a more complicated CSV file:
"psmith01 abc", "CLASS2B " , " Peter...
Result:
Line 1 has 4 values:
|psmith01 abc|
|CLASS...
The third line is invalid input, but throwing a Java IOException is a bit grave. Also, the parser is not able to escape a backslash.
Add a new line in item two:
"One", "Two
", "Three"
Result:
Line 2 has 3 values:
|One|
|Two
|
|...
Created by Dr. Xi on June 21, 2011 15:54:00
Last update: June 22, 2011 11:33:09
Demo code for CSV parsing with SuperCSV parser .
Java code:
import java.io.*;
import java.util.List;
imp...
Test with a simple CSV file:
psmith01,CLASS2B,Peter Smith 1,YEAR2,1,N,ADVANCED,...
The parser worked correctly:
Line 1 has 11 values:
|psmith01|
|CLASS2B|...
Test with a more complicated CSV file:
"psmith01 abc", "CLASS2B " , " Peter...
The parser messed up on all three lines:
Line 1 has 5 values:
|psmith01 abc|
|CLASS...
Using two lines input:
"psmith01 abc", "CLASS2B " , " Peter...
It generates an exception:
Line 1 has 5 values:
|psmith01 abc|
|CLASS...
Add a new line in item two:
"One", "Two
", "Three"
Result:
Line 2 has 3 values:
|One|
|Two
|
|...
Created by Dr. Xi on June 22, 2011 07:12:02
Last update: June 22, 2011 11:32:02
Demo code for CSV parsing with OstermillerUtils .
Java code:
import java.io.*;
import java.util.List;
imp...
Test with a simple CSV file:
psmith01,CLASS2B,Peter Smith 1,YEAR2,1,N,ADVANCED,...
The parser worked correctly:
Line 1 has 11 values:
|psmith01|
|CLASS2B|...
Test with a more complicated CSV file:
"psmith01 abc", "CLASS2B " , " Peter...
The parser messed up on all three lines:
Line 1 has 6 values:
|psmith01 abc|
| "CLA...
Putting a space before the first quote:
"Smith, Jack","210-345-8888"
It dismissed the quotes:
Line 1 has 3 values:
| "Smith|
| Jack"|
...
Add a new line in item two:
"One", "Two
", "Three"
Result:
Line 1 has 2 values:
|One|
| "Two|
...
