Wednesday, September 21, 2011

Tech Review: Wednesday, September 21, 2011

Working with porting C# to Java today.

  • It is sort of like a class because you can override method inside the enum.
    • @Override public String toString() {....}
Struct like objects in Java:  
  • Has lots of really nice and clear comparisons.
  • I need to read the whole thing
Ternary or conditional operator in Java:  http://www.janeg.ca/scjp/oper/ternary.html
  • operand1 ? operand2 : operand3;
    • operand1 must be a boolean value or experssion
The C# dictionary is similar to the Java Map interface:  
The ArrayList Generic Class in Java:
The C# ICollection interface:

A Java tutorial on collection interfaces:  
Today I was confused as to why code would compile in my simple command line program and not in Eclipse.
  • Sometimes the error messages in Eclipse are miss leading
  • I was trying to write code in the class body outside a method
  • if (child == null) child = new Lista(c, null);
A tutorial on Eclipse:

Java Properties and C# properties are not the same thing at all:  http://download.oracle.com/javase/1.4.2/docs/api/java/util/Properties.html
  • C# properties are a value in the object
  • Java properties are a way of saving the state to a file and reading it back
Another very nice Java/C# Comparison:  http://www.harding.edu/fmccown/java_csharp_comparison.html
  • This one would be best to read first
Java random number generation:
In doing Repast Simphony development, the RandomHelper class should be used:
A very nice example of a Java singleton implementation:  http://www.javaworld.com/javaworld/jw-04-2003/jw-0425-designpatterns.html

Default parameters in Java:
Declaring generic arrays:
  • http://forums.techarena.in/software-development/1117589.htm
    • HashMap <?,?> [] x = new HashMap <?,?>[3];
      • this work but I could access 'x'
    • Best to avoid and wrap in a list instead
      • List<HashMap<Class, Class> x = new ArrayList<HashMap<Class1, Class2>(3);
      • the above code may not be correct, but it has the idea
C# ArgumentException can be changed to a Java IllegalArgumentException:  https://forums.oracle.com/forums/thread.jspa?threadID=472866

  • performance advantages in C#
For each Loop in Java:
Generics and array construction in Java:
Comparison between Java HashMap and .NET Hastable:  http://www.microsoft.com/mspress/books/sampchap/6173.aspx#116

  • List myList = new ArrayList (collection);
  • Collections.sort (mylist);