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0) Eclipse shortcuts (9-Sep-20)

Eclipse shortcuts

1) Java integration notes and compiling for Java 11 from Java 8 (6-Sep-20)

Java integration notes

2) List FileUtils.GetFiles(String directory) (6-Sep-20)

How to get a list of files from a directory


/*
********************************************************
* GetFiles
********************************************************
*/
List FileUtils.GetFiles(String directory)
{
	File dir = new File(directory);
	return ConvertArrayToList(dir.list());
}

3) Java API and references 2020 (6-Sep-20)

Java API and references 2020

5) working with regular expressions in Java (19-Aug-20)

working with regular expressions in Java

6) Working with date and time (14-Aug-20)

Working with date and time

7) Expression language notes (13-Aug-20)

Expression language notes

9) Working with JUnit (12-Aug-20)

Working with JUnit

10) Language files (11-May-19)

Language files

11) Concurrency and Hashmaps in Java (19-Jun-17)

Concurrency and Hashmaps in Java

12) How can I create a string stream to write to? (18-Jun-17)

StringWriter s = new StringWriter();
PrintWriter out = new PrintWriter(s);
...write something to out
StringBuffer output = s.getBuffer();

Click on the item above to see more.

13) Jaxb 2.0 tutorial (15-Jun-17)

Goal

Realize the reflection based architecture of Jaxb
Plan a sample project for exercising Jaxb
Prerequisites
Resources and how best to use them

Reflection based architecture

jaxb 2.x architecture supports metadata based marshalling and unmarshalling of xml. This makes xsd optional unlike the jaxb 1.x architecture

Tutorial Project

The project is a simple project where an xml file is marshalled and unmarshalled using jaxb 2.x. All of the files needed to accomplish this are provided on the right hand side of the menu.

14) How to get the system temp directory (14-Jun-17)


public static String getSystemTempDirectory()   
{
    return System.getProperty("java.io.tmpdir");
}

15) What is the state of Java Serialization in Java 8 and up? (14-Jun-17)

What is the state of Java Serialization in Java 8 and up?

17) Whats up with go langguage? (14-Jun-17)

whats up with go?

18) Future of IDEs? Eclipse? (14-Jun-17)

Future of IDEs? Eclipse?

19) Java coding guidelines (4-Oct-14)

Java coding guidelines

20) Dynamic Proxies (30-Aug-14)

Dynamic Proxies

21) How to work with arrays (29-Aug-14)

How to work with arrays

22) What is a static java class? (27-Jul-14)

What is a static java class?

23) What is volatile in Java? (5-Jul-14)

What is volatile in Java?

24) 04.05 Java Programming NOtes (23-Jun-14)

You can use this reference page as a cheatsheet while programming in java

26) Whats up with Java Override? (9-May-14)

For some time now Java compilers allow you indicate some methods in your class definition as overridden methods.

You do this by annotating the method signature with a code snippet such as


@Override
public void somemethod(){}

By doing so you tell the compiler to see if this annotated method exists in base classes or in the inheritance hierarchy. If it is, nothing happens. If it isn't you, the programmer, have made a mistake, because you expected it to be there. So perhaps misspelled it.

In JDK 1.5 this annotation will throw an error if the method is abstract in the base class.

Either it is corrected or deemed more useful in later JDKs and you can now safely provide this annotation on methods whose baseclass representations are abstract.

this annotation will also guard against some of the base class changes where a method is removed which is overridden in derived classes. You now will know that that happened.

this protection is especially important in frameworks where lot of callbacks are used like the container managed Android components.

bottom line, say @override if you expect this method to be in the base class and you are overriding it.

27) Understand javax.activation.DataSource etc... (13-Apr-14)

Understand javax.activation.DataSource etc...

28) Why is it not a bad idea to delete things at garbage collection time! (13-Apr-14)

Why is it not a bad idea to delete things at garbage collection time!

29) A computer language must pass its teach-ability test to a middle school-er!! (3-Nov-13)

A computer language must pass its teach-ability test to a middle school-er!!

30) Does a default constructor call the baseclass constructor? (3-Nov-13)

Does a default constructor call the baseclass constructor?

31) Be wary of constructors invoking virtual methods directly or indirectly! (3-Nov-13)

Be wary of constructors invoking virtual methods directly or indirectly!

32) Coordinated flight pattern for Objects (31-Oct-13)

Coordinated flight pattern for Objects

33) Build health monitors into your source code (31-Oct-13)

Build health monitors into your source code

34) Multiple class inheritance in Java (22-Oct-13)

Multiple class inheritance in Java

35) Pattern of constraining an object construction (19-Oct-13)

Pattern of constraining an object construction

36) A construction pattern for dependent objects (19-Oct-13)

A construction pattern for dependent objects

37) java: How should we use Date and Calendar objects in Java? (31-Oct-12)

Description to be entered

38) What are the Java projects in Apache? (29-Sep-12)

What are the Java projects in Apache?

39) What is a weak reference? (14-Aug-12)

What is a weak reference?

40) What is Refinery CMS? (19-Jun-12)

What is Refinery CMS?

41) What is Stripe? (19-Jun-12)

What is Stripe?

42) Addressing Code Quality in Enterprises (9-Jun-12)

I have a medium to a large enterprise. The software we are producing is buggy. It is brittle. It often fails. It is often down. It often allows me to delete things that I shouldn't be able to. It takes too long to respond. It is slow. It gives unexpected results. It doesn't stop me from shooting myself in the foot. Why does this happen and how can I improve the state of code quality in my enterprise?

43) windows azure cloud (7-Jun-12)

windows azure cloud

44) Life and Careers (26-May-12)

Life and Careers

45) Whats up with Cloud IDEs? (17-May-12)

Whats up with Cloud IDEs?

46) Whats up with OpenData? (17-May-12)

Whats up with OpenData?

47) So where are the java clouds (17-May-12)

So where are the java clouds

48) Java string substitution/formatting and variable args (12-May-12)

Java string substitution/formatting

49) Typed languages are nice (5-May-12)

In bouts of romanticism (I am prone) and expediency I do like type less languages, but for maintenance and sure-footing and transparency typed languages like Java, when paired (may-be-must) with a right tool like eclipse, are a pleasure to program in.

There will be times in the near future one may be able to see objects as both typed or open ended structures (such as type less arrays) to provide just-in-time objects.

50) How to use an assert: JDK 1.4 Programming With Assertions (23-Apr-12)

http://java.sun.com/j2se/1.4.2/docs/guide/lang/assert.html

A very nice document on the usage and motivations behind assertions in JDK 1.4

51) what does Azure has for Java? (16-Apr-12)

what does Azure has for Java?

52) java/samplecode: Using static initialization (9-Apr-12)

Static initaliazation

53) Java memory settings (14-Apr-11)

Java memory settings

54) walking through java enumeration (2-Jan-11)

walking through java enumeration

55) Jar finder: Pretty neat (28-Dec-10)

Jar finder

Pretty neat

An example to find org.apache.xpath.XPathAPI.

56) Java and Browsers (23-Dec-10)

Java and Browsers

57) jsp caching expire tag (28-Jul-09)

jsp caching expire tag

58) Sample code for arrays (27-Jun-09)

Sample code for arrays

59) How to explore android source code (12-Dec-08)

How to explore android source code

Where is the source code web site?
Can I get java source for just the android.jar?
Can I browse sources online?
How can I debug into android java source code from eclipse?

Click on the link above for full details and other helpful links.

60) Collections: How to use the collections API (16-Aug-08)

http://java.sun.com/developer/technicalArticles//Collections/Using/#toi

source:sun
complexity:medium
depth:medium
style:verygood

61) how to use thread local in java (11-Aug-08)

how to use thread local in java

62) Research notes on Master Data Management (3-Jul-08)

Research notes on Master Data Management, Common Data Models, Customer Data hubs.

63) A bookmark for a nice collection of java articles (24-May-08)

Available from IBM IT Skills Development center the following link provides a number of collected articles across the web. I am planning on reading them in my spare time.

See the list of articles.

I must warn you however that there is a couple of years old article from me that made the list. That should make this list suspect to its profoundness :). However there seem to be other topics of weightyness that I feel comfortable with the recommendation.

64) jsp based masterpage capabilities in Aspire: implementation notes (29-Apr-08)

These notes illustrate an interesting way of developing and using capture tags in jsp to accomodate masterpages or tiles. This specific example talks about how this is done in AspireWeb but the ideas can be easily extended to any java based server side framework.

The notes will explore a) how to define a jsp page in response to an incoming url in an MVC fashion b) it then goes into identifying a tiles or masterpage pertaining to that URL c) an example of the master page d) an example of the jsp page with capture tags e) the resulting out put combining the master page and the url specific jsp page. f) what the incoming url will look like

65) How to redirect from a jsp page server side? (25-Apr-08)

1. How can I enable a site for crawling better?

2. How to use jsp forward?

3. How can I pass parameters to a forward?

4. How can I retrieve parameters from a forward?

5. what is the odd behavior of a request when it is forwarded?

6. Can I forward between two contexts?

7. How to simulate a forward between contexts?


<jsp:forward page="<%=targeturl%>"/>

66) walking through a "string" full of characters: StringCharacterIterator (8-Nov-07)

private int getNumberOfParameters(String ps)
   {
   		int count=0;
   		StringCharacterIterator sci = new StringCharacterIterator(ps);
   		for(char c=sci.first();c != CharacterIterator.DONE; sci.next())
   		{
   			if (c == '?')
   			{
   				count++;
   			}
   		}
   		return count;
   }//eof-function

67) CVS Notes (29-May-07)

Notes to help with CVS

68) Sample code for html encoding a string (11-May-07)


   public static String htmlEncode(String inHtmlString)
   {
	   String fromCharString="<>&";
	   String[] toStringArray = { "&lt;", "&gt;", "&amp;" };
	   return encode(inHtmlString, fromCharString, toStringArray);
   }

Escape Special Characters from Java Best Practices

69) In search of Transparent Services : jax-rpc, WSIF, Axis, jax-ws (15-Jan-07)

How can I access a local java class or a soap representation of it at run time with out using any stubs. Assuming I have the interface of the class and the domain objects for it.

Need you help. What is a good approach for accessing java interfaces remotely and in a transparent fashion?

What is a good approach for accessing java interfaces remotely? The answer seems too obvious. Use EJB session beans, or web services or RMI. is that the best way? Could I not use dynamic proxies and not use any client side or serverside skeletons and stubs? Can I not do this by not generating any thing? Would some one recommend WSIF to do this? What else is out there?

Phrased differently, if I have a jar file that contains an interface and the domain objects that support that interface, can I access one of its implementations that is sitting on a remote machine using a dynamic proxy. The protocol can be SOAP or EJB or just a plain homegrown over http for that matter.

Stated differently, if I were to implement a service layer using plain java interfaces and implementations, can I break that layer apart at deployment time with out involving any compile time changes. Such an option will give me the ability to multi-tier an application with very little fan fare. Programmers need even not know about SOAP or EJB etc.

For instance WSIF (web services invocation framework) seem to advertise a functionality that is similar in intent. But someone expereienced with WSIT comment on whether all you need is interfaces and domain objects? Also WSDL seem to be necessary for WSIF to work. Can it work with out any xml artifacts and assume a certain SOAP implementation and provide a dynamic proxy for it.

I am hoping someone out there looked into this before and I would like to hear from them. Either you can post the answer here or if you don't have an account, could you email me your opinion? My email is "satya at activeintellect.com".

Thanks in advance for considering this.

70) A java thread time slice duration and performance implications (29-Dec-06)

java time slice duration performance

71) How do I know if a class inherits from another class? (2-Oct-06)

Class baseClass;
Class derivedClass;

if (baseClass.isAssignableFrom(derivedClass))
{
     System.out.println(
                 "derviedClass is derived from baseClass"
                 + "or assignable a bit more precisely");
}

72) Reflections on the importance of HTML prototyping for IT (11-Aug-06)

Wonder if you have come across these lines before:

"I fix myself an Omelete, sir,
Of fluffy clouds, and sky
...
I sew myself a warm cloak, sir,
of hope and daffodils."

Unlike this fanciful dilemma of "Poor Angus" of Shel Silverstein, in large IT corporations HTML prototypes can play a much more significant role. They can aid faster development times. They can secure budgets. They can encourage good architecture. They can directly lead to a number of development artifacts such as data models, and business services. I think prototypes offer another important aspect to the modern development process along with the Extreme Programming and RUP.