After answering a question about Java Assertions today, a short how to seems a good idea.
Assertions - An easy way to put optional tests in your Java source.
Enabling Assertions - By default assertions are disabled, to enable them add a switch to the java command line.
java -ea MyProgram
-ea is short for
Writing an Assertion - There are two possible formats.
assert x > 1;
assert x > 1:"My special error message here";
If the statement is true, nothing happens. If false, an exception is thrown and the program stops executing.
Testing if Assertions are Enabled - The easy way is to just put a false assertion in your