[jsword-devel] java assertions

[DM Smith]

I was curious about java's assertions since I have not used them.
http://java.sun.com/j2se/1.4.2/docs/guide/lang/assert.html gives a tutorial.
According to 
http://leepoint.net/notes-java/20language/30statements/40assertions/20assert-usage.html 
:
    You need to compile with the -source 1.4 flag to prevent assertions from 
being compiled out.
    You need to run the program with -ea or -enabledassertions as an 
argument to the vm.

Because assertions may be compiled out, the test must be free of side 
effects.

When the argument to an assert is false, it throws an AssertionError.
A second argument can be supplied to an assertion to provide greater detail 
that analysis of the code could not.

This can easily replace many uses of LogicError, but not when the purpose is 
to rethrow caught Exception.

if (a == b)
{
    throw new LogicError("Oops");
}

can become:
assert a!=b;

However:
try
{
    doit();
}
catch (Throwable t)
{
    throw new LogicError(t);
}

would become:
try
{
    doit();
}
catch (Throwable t)
{
    assert false : t.getMessage();
}

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