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Created by Dr. Xi on May 25, 2012 15:47:34    Last update: May 25, 2012 15:49:33
Steps to configure SSL for Apache HTTPD server on Windows: In Apache2.2/conf/httpd.conf , load mod_ssl and include httpd-ssl.conf : LoadModule ssl_module modules/mod_ssl.so ... In Apache2.2/conf/extra/httpd-ssl.conf , make sure the paths for the cert files point to the cert and key you want to use: # Server Certificate: # Point SSLCertificat... Start up Apache. If it fails, use the command line to see what the error is. There won't be any log in error.log if there are errors in the conf files: C:\Program Files (x86)\Apache Software Foundation\... I corrected the previous error by using the alternative line for SSLSessionCache : # Inter-Process Session Cache: # Configure ...
Created by Fang on March 06, 2012 12:25:33    Last update: March 06, 2012 12:25:33
In the bean validation API javadoc, for every constraint annotation, there's a corresponding .List annotation. For example, for @NotNull , there's @NotNull.List , for which JavaDoc says: Defines several @NotNull annotations on the same element What would you accomplish with multiple @NotNull annotations that you cannot accomplish with one @NotNull ? This is a test to reveal some of the facts. Change the Person class to: package com.example; public class Person { ... Add another JUnit test ( src/test/com/example/TestPersonWithList.java ): package com.example; import java.util.Itera... As the test shows, a Person bean can never be valid because we are requiring that name must begin with Mr and Ms . One might think that the same can be accomplished by simply repeating the @Pattern annotation multiple times,...
Created by Fang on March 06, 2012 12:24:53    Last update: March 06, 2012 12:24:53
Validation groups can be used to control which rules validation rules to run. A validation group can be identified by any Java interface (not class!). Multiple validation groups may be specified when validating. In this example, I added a validation group named MyValidationGroup ( src/main/java/com/example/MyValidationGroup.java in Maven project): package com.example; public interface MyVal... and added a @Size rule for a person's name, because my database can only store up to 15 characters for a person's name: package com.example; import javax.validatio... Now validate Person with a JUnit test ( src/test/java/com/example/TestPersonWithGroup.java in Maven project): package com.example; import java.util.Set; ... Test with " mvn clean test ". The rules where groups is not specified, which belong to the javax.validation.groups.Default group, are not executed with these tests.
Created by Fang on March 06, 2012 12:24:05    Last update: March 06, 2012 12:24:05
A bean class may also be defined through composition. The validation rules of referenced beans are not automatically called when a composite bean is validated. You need to use the @Valid annotation to trigger cascade validation. As an example, I create a class named AccountPerson2 , which contains a Person with the addition of an email field ( src/main/java/com/example/AccountPerson2.java in Maven project): package com.example; import javax.validatio... Now validate AccountPerson2 with a JUnit test ( src/test/java/com/example/AccountPerson2Test.java in Maven project): package com.example; import java.util.Set; ... Test with " mvn clean test " and you'll see that the validation rules of the Person class are executed when an AccountPerson2 bean is validated. Without the @Valid annotation, the validation rules of Person will not be called.
Created by Fang on March 06, 2012 12:22:48    Last update: March 06, 2012 12:22:48
When a bean class inherits another class, the validation rules of the parent class is automatically executed when a child class bean is validated. As an example, I create a class named AccountPerson , which inherits the Person class with the addition of an email field ( src/main/java/com/example/AccountPerson.java in Maven project): package com.example; import javax.validatio... Now validate AccountPerson with a JUnit test ( src/test/java/com/example/AccountPersonTest.java in Maven project): package com.example; import java.util.Set; ... Test with " mvn clean test " and you'll see that the validation rules of the Person class are executed when an AccountPerson bean is validated.
Created by Fang on March 05, 2012 20:32:37    Last update: March 05, 2012 20:32:37
In this simple example, I create a simple validating bean and create a JUnit test to test the validation. The bean ( src/main/java/com/example/Person.java ): package com.example; import javax.validatio... The test ( src/test/java/com/example/TestPerson.java ): package com.example; import java.util.Set; ... Run the test: mvn clean test You'll notice that one test passed and the other failed. The tests require that a person must have a name and the name cannot be empty, so @NotNull is not the right rule to use here. To make sure that the name is not empty, we need to use @Pattern . But since a null String matches any pattern, @NotNull is also needed: package com.example; import javax.validatio...
Created by freyo on October 28, 2010 23:00:48    Last update: August 23, 2011 08:51:42
Running " adb shell procrank ": root@android:/ # procrank ... Column Name Meaning VSS Virtual Set Size: how much virtual memory associated with process RSS Resident Set Size: how much physical pages allocated for the process. Pages shared between processes are counted multiple times PSS Proportional Set Size. Take the RSS number but evenly distribute shared pages among the sharing processes. For example, if three processes are sharing 3MB, each process gets 1MB in PSS. USS Also known as Private Dirty, which is basically the amount of RAM inside the process that can not be paged to disk (it is not backed by the same data on disk), and is not shared with any other processes. Reference: How to discover memory usage of my application...
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 freyo on May 09, 2011 12:50:52    Last update: May 09, 2011 12:51:54
You can use the android.os.StatFs class to check for available space on the sd card. Example code: // import android.os.Environment; // import...
Created by Dr. Xi on March 24, 2011 12:11:14    Last update: March 24, 2011 12:22:03
This is the task: your client wants to know how the web application is used. That is pretty easy. A plethora of commercial tools or any of the free log analysis tools such as analog and AWStats would fit the bill. But here's the catch: they want to know not only what pages are visited by how many people and when, but also who logged in and did what. Your application is using form based authentication and therefore, everyone is anonymous in the web access log. What to do? This is a servlet filter that generates a web access log with authenticated user info that can be fed to log analysis tools such as analog and AWStats . Filter code (the output format is Apache...
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