Java language and library suggestions

Hello!
If I have a suggestion for extending the Java language and library,
what is the right place to discuss it?

I include a few things that I came across lately and would like to
have in Java. I will appreciate your comments.

1. introduce method
int String.byteLength(Charset charset);
that would return the length of the string in bytes in the given
charset. This would avoid calling String.getBytes(charset).length,
thus avoid allocating the byte array.

2. allow to specify character encoding for PrintStream. Java 6 SE's
PrintStream prints the characters in platform's default character
encoding.

3. Catch multiple exception types at once. The syntax could be
something like
try {
   ...
} catch(MalformedURLException, UnsupportedEncodingException as
IOException e){
   // handle IOException e
}

4. Sometimes having to catch an exception that will never be thrown is
really annoying.
For example, I would like to write something like

@safe
URI uri = new URI("http://valid.uri.com/");

instead of

URI uri;
try {
   uri = new URI("http://valid.uri.com/");
} catch(URISyntaxException e) {
   throw new AssertionError(e);
}

I used the annotation notation, but I doubt something like this can be
achieved with annotations. It would be nice if the language had a
construct to mark some code exception safe and if it threw an
exception, it would result in AssertionError. It could also be more
flexible, like this

@safe(NumberFormatException, UnsupportedEncodingException)
{
   // statement that should not throw any NumberFormatException or
UnsupportedEncodingException
   // and if it does, it is an AssertionError
}