Re: switch using strings

From:

Robert Klemme <shortcutter@googlemail.com>

Newsgroups:

comp.lang.java.programmer

Date:

Tue, 01 Mar 2011 23:03:49 +0100

Message-ID:

<8t58q5F2usU2@mid.individual.net>

On 02/21/2011 05:14 PM, rossum wrote:

On Sun, 20 Feb 2011 21:35:10 -0500, Arne Vajh=C3=B8j<arne@vajhoej.dk>
wrote:

On 20-02-2011 17:31, Dirk Bruere at NeoPax wrote:

On 20/02/2011 21:26, Arne Vajh=C3=B8j wrote:

On 20-02-2011 16:25, Arne Vajh=C3=B8j wrote:

On 20-02-2011 16:24, Dirk Bruere at NeoPax wrote:

...which obviously won't work.
I have a series of packets coming in with a header that contains a=

message name in text. I need to find a neat way to do a kind of sw=

itch

statement on the message name. Any ideas?

Multiple if statements.

I thought you might say something horrible like that

Why is that so horrible.

if(s.equals("x")) {
     ...
} else if(s.equals("y")) {
     ...
} else if(s.equals("z")) {
     ...
} else {
     ...
}

is simple, readable and most likely fast enough.

Unless you can wait for Java 7, which I believe
is supposed to get switch on strings.

It's Android, so no.

They will also go Java 7 syntax at some point in time.

Arne

Or use a multiple-exit method:

   int String2MessageIndex(String messName) {
     if (messName.equals("This")) { return 0; }
     if (messName.equals("That")) { return 1; }
     if (messName.equals("The other")) { return 2; }
     if (messName.equals("Something")) { return 3; }
     if (messName.equals("Different")) { return 4; }
     // As many more as needed ...

     // Default return value.
     return UNRECOGNIZED_MESSAGE;
   }

Well, this would be better implemented using a Map. And even if you
need to execute code you can define an interface (or base class) and
retrieve it from the Map via the String as key. Then execute it.

Cheers

robert