This is not a ground breaking thing but something I learned a few weeks ago. I've been learning java for the past few months and its a whole different world than php, perl or ruby. I learned how to use standard in from my professor a few week ago. Say you have a program like this, where you want to get some user input.

PLAIN TEXT
JAVA:
  1. import java.util.ArrayList;
  2. import java.util.Scanner;
  3.  
  4.  
  5. public class Example2 {
  6.  
  7.     /**
  8.      * @param args
  9.      */
  10.     public static void main(String[] args) {
  11.         Scanner input = new Scanner(System.in);
  12.         ArrayList<String> studentList = new ArrayList<String>();   
  13.        
  14.         System.out.println("Enter names separated by \n or space, Q to quit");
  15.         while(input.hasNext()) {
  16.             String userInput = input.next();   
  17.             if (userInput.equalsIgnoreCase("Q")) {
  18.                 break;
  19.             } else {
  20.                 studentList.add(userInput);
  21.             }
  22.            
  23.         }
  24.        
  25.         for (String name : studentList) {
  26.             System.out.println("Name is: " +name);
  27.         }
  28.     }
  29.  
  30. }

Modifying the program slightly, you can accept standard input like:

PLAIN TEXT
JAVA:
  1. import java.util.ArrayList;
  2. import java.util.Scanner;
  3.  
  4.  
  5. public class Example {
  6.  
  7.     /**
  8.      * @param args
  9.      */
  10.     public static void main(String[] args) {
  11.         Scanner input = new Scanner(System.in);
  12.         ArrayList<String> studentList = new ArrayList<String>();   
  13.        
  14.         while(input.hasNext()) {
  15.             String name = input.next(); 
  16.             studentList.add(name);
  17.            
  18.         }
  19.        
  20.         for (String name : studentList) {
  21.             System.out.println("Name is: " +name);
  22.         }
  23.     }
  24.  
  25. }

Then you can run the program on the command line like this:

$ java Example < sample_data.txt
Name is: Bob
Name is: Charles
Name is: Henry
Name is: Emery
Name is: Chad

Not too earth shattering but may help you make a simple program easier to test!