Why eclipse doesn't recompile last changes made to my Java classes?

Question

I have a simple file with just 1 line that prints "Hello World" inside main. I execute it and it prints "Hello World" on eclipse console. Now when I change the string to "Bye world" it still prints "Hello World". Infact if I cause a syntax error by modifying println to prrrintln. it still prints "Hello World". What can cause eclipse to not use the latest file ? When I try to run it from command line, I get the following error:

bin> java WordBreakProblem.class 
Error: Could not find or load main class WordBreakProblem.class

Is there a correlation between two issues here?

Answer 1

1. Have Build Automatically checked

2. The correct way to run WordBreakProblem class is

java WordBreakProblem

instead of

java WordBreakProblem.class

Also make sure you compile the java source code into WordBreakProblem.class by using

javac WordBreakProblem.java

before doing step 2.

3. If the code still doesn't refresh, try "clean".