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Created by Fang on March 30, 2012 10:07:25
Last update: March 08, 2013 13:41:57
After a user resets a password, I want to force the user to change the password before she gets access to secured content. This is usually done with a servlet filter. But with Spring MVC, you can also use a HandlerInterceptor . According to Spring JavaDoc: HandlerInterceptor is basically similar to a Servlet 2.3 Filter, but in contrast to the latter it just allows custom pre-processing with the option of prohibiting the execution of the handler itself, and custom post-processing. Filters are more powerful, for example they allow for exchanging the request and response objects that are handed down the chain. Note that a filter gets configured in web.xml, a HandlerInterceptor in the application context. As a basic guideline, fine-grained handler-related preprocessing tasks are candidates...
Created by Dr. Xi on August 15, 2012 12:05:39
Last update: August 15, 2012 12:05:39
Use OpenSSL's s_client command to fetch a page manually:
$ openssl s_client -connect localhost:443 -state -...
Sample session for Google:
$ openssl s_client -connect www.google.com:443 -st...
Resource: SSL/TLS Strong Encryption: FAQ
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 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 freyo on September 29, 2011 16:01:31
Last update: September 29, 2011 16:09:37
With standalone broadcast receiver
AndroidManifest.xml :
<?xml version="1.0" encoding="utf-8"?>
<manifes...
Java code:
package com.android.networkreceiver;
import...
Register listener inside Activity programmatically
AndroidManifest.xml :
<?xml version="1.0" encoding="utf-8"?>
<manifes...
Java code:
package com.android.networklistener;
import...
Register/unregister broadcast receiver in onResume / onPause works because the connectivity change broadcast is sticky . I intentionally used two registerReceiver calls in onResume to demonstrate this - onReceive will be called once for each registration.
Created by freyo on May 13, 2011 15:45:29
Last update: September 20, 2011 08:08:12
This is an Android app that dumps any binarized xml file as plain text - to the sdcard on the device or emulator.
build.xml :
<?xml version="1.0" encoding="UTF-8"?>
<project...
AndroidManifest.xml
<?xml version="1.0" encoding="utf-8"?>
<man...
res/layout/main.xml
<?xml version="1.0" encoding="utf-8"?>
<Lin...
res/values/strings.xml :
<?xml version="1.0" encoding="utf-8"?>
<res...
src/com/android/xmltool/DumpXml.java
package com.android.xmltool;
import java.ut...
Screenshot
Pre-built APK can be downloaded from: http://code.google.com/p/android-binxml-dump/
Created by freyo on August 25, 2011 09:07:40
Last update: August 25, 2011 20:45:43
This is a list of built-in Android permission values: Permission Description Since API Level android.permission.ACCESS_CHECKIN_PROPERTIES Allows read/write access to the "properties" table in the checkin database, to change values that get uploaded. 1 android.permission.ACCESS_COARSE_LOCATION Allows an application to access coarse (e.g., Cell-ID, WiFi) location 1 android.permission.ACCESS_FINE_LOCATION Allows an application to access fine (e.g., GPS) location 1 android.permission.ACCESS_LOCATION_EXTRA_COMMANDS Allows an application to access extra location provider commands 1 android.permission.ACCESS_MOCK_LOCATION Allows an application to create mock location providers for testing 1 android.permission.ACCESS_NETWORK_STATE Allows applications to access information about networks 1 android.permission.ACCESS_SURFACE_FLINGER Allows an application to use SurfaceFlinger's low level features 1 android.permission.ACCESS_WIFI_STATE Allows applications to access information about Wi-Fi networks 1 android.permission.ACCOUNT_MANAGER Allows applications to call into AccountAuthenticators. Only the system can get this permission. 5 android.permission.AUTHENTICATE_ACCOUNTS...
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 freyo on May 17, 2011 11:13:17
Last update: May 17, 2011 11:13:17
This is an odd-ball content provider in that it doesn't provide database records, but provides a resource as a stream. It can be used to provide media files or XML resources. Start the project with:
tools/android create project --package com.android... Create assets directory and add an XML file ( assets/demo.xml ): <? xml version="1.0" encoding="UTF-8"?> <people... Edit the layout ( res/layout/main.xml ): <?xml version="1.0" encoding="utf-8"?> <LinearL... Edit src/com/android/cptest/Dummy.java : package com.android.cptest; import java.io.... Add content provider ( src/com/android/cptest/XmlResource.java ): package com.android.cptest; import java.io.... Update AndroidManifest.xml : <?xml version="1.0" encoding="utf-8"?> <manifes... Add this section to the end of build.xml : <target name="-package-resources"> <ech... Build and install: ant install Screenshot: Remove the Dummy activity ( AndroidManifest.xml ): <?xml version="1.0" encoding="utf-8"?> <manifes... Create a new project for...