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Created by voodoo on August 03, 2012 08:42:38    Last update: August 03, 2012 09:31:25
The C function getsockopt lets you get the error codes with the option SO_ERROR . The possible error numbers are defined in the global errno.h . The relevant values are: #define ETIMEDOUT 110 /* Connection timed out */ ... But here's the whole list on my Linux system ( /usr/include/asm-generic/errno.h ): #ifndef _ASM_GENERIC_ERRNO_H #define _ASM_GENER...
Created by Fang on February 21, 2012 20:33:58    Last update: February 21, 2012 20:33:58
You can customize Tomcat error page with error code: <error-page> <error-code>404</error-code> ... or Java exception type: <error-page> <exception-type>java.lang.Throwab... Either error-code or exception-type is required, but not both. There's no way to aggregate error codes, such as: <!-- This does not work! --> <error-page> ... Customizing error pages is about the only way to suppress the default stack trace in Tomcat in case of an unhandled exception.
Created by James on February 02, 2012 09:20:22    Last update: February 02, 2012 09:20:22
This example came from the jQuery validation documentation. The required rule can be used to validate a required selection box when you set the value of the first option to empty. <!DOCTYPE HTML> <html> <head> <scrip... The error message is the title since no error message is specified. A more fully defined validation check would look like this: $('#my-form').validate({ errorElement: "p", ...
Created by Fang on November 28, 2011 21:04:15    Last update: November 28, 2011 21:04:15
Some innocent looking JavaScript may cause a fatal error in a Facelet page. For example: <script type="text/javascript"> if (items.lengt... or <script type="text/javascript"> // jQuery code ... Because Facelet is strict XML, therefore, < and > must be escaped. There are several ways to deal with this: Do not embed JS code directly in the page. Put the code in .js files and include it in the page with the src attribute. Put JS code in a CDATA section: <h:outputScript target="head"> <![CDATA... Use XML entities: <script type="text/javascript"> // jQuery code ...
Created by freyo on September 07, 2011 16:46:14    Last update: September 07, 2011 19:23:00
The Android unit test framework is based on JUnit 3 , not JUnit 4. Test cases have to extend junit.framework.TestCase or a subclass (such as android.test.InstrumentationTestCase ). Tests are identified by public methods whose name starts with test , not methods annotated with @Test (as in JUnit 4). An Android test suite is packaged as an APK, just like the application being tested. To create a test package, first you need to identify the application package it is testing. Google suggests to put the test package source in a directory named tests/ alongside the src/ directory of the main application. At runtime, Android instrumentation loads both the test package and the application under test into the same process. Therefore, the tests can invoke methods on...
Created by Dr. Xi on July 11, 2011 12:24:10    Last update: July 11, 2011 12:25:44
This code snippet import java.util.*; public class UncheckedCast ... fails with a compilation error and a warning: $ javac -Xlint:unchecked UncheckedCast.java Unc... Because List<String> is not a reifiable type, the Java Runtime does not have enough information to verify the type or do the type casting. This is fixed by changing List<String> to List<?> (or to the raw type List ): public static void main(String[] args) { Ob...
Created by James on January 10, 2011 16:37:20    Last update: January 10, 2011 16:37:20
The following page injects CSS rules with JavaScript. It works fine in Firefox and Chrome. <html> <head> <script type="text/javascrip... But in IE, it breaks with "Unknown runtime error" (seemed like it's trying to interpret the curly brackets in the CSS as JavaScript blocks!): In order to make it work in IE, the code need to be changed to: <html> <head> <script type="text/javascrip... The tricks to identify IE and insert new CSS rules came from Paul Irish .
Created by voodoo on July 11, 2009 15:14:55    Last update: July 29, 2010 22:45:48
cURL is a command line tool for transferring files with URL syntax. The main purpose and use for cURL is to automate unattended file transfers or sequences of operations. It's really easy to see HTTP headers with curl: C:\>curl --head http://www.google.com HTTP/1.0 ... or, headers and page together (dump headers to stdout): $ curl --dump-header - http://www.google.com HTTP/... Download openssl from openssl.org: curl http://www.openssl.org/source/openssl-0.9.6m.... C:\>curl --help Usage: curl [options...] <url> ...
Created by Dr. Xi on February 10, 2010 23:39:37    Last update: February 10, 2010 23:39:37
Example web.xml that includes most frequently used elements. This sample is for Servlet Specification 2.4. <?xml version="1.0" encoding="UTF-8"?> <web-ap...
Created by Dr. Xi on January 30, 2009 16:57:12    Last update: January 30, 2009 17:25:36
The scriptable attribute defaults to false . However, even when you set it to true , there is a time delay between when the applet is loaded and when it becomes scriptable . The following code may fail: <html><body> <object classid="clsid:8AD9C840-04... You need to wrap the JavaScript like this: <script language="JavaScript" type="text/javascrip...