Return-Path: Delivered-To: apmail-hadoop-common-user-archive@www.apache.org Received: (qmail 42236 invoked from network); 11 May 2010 14:59:59 -0000 Received: from unknown (HELO mail.apache.org) (140.211.11.3) by 140.211.11.9 with SMTP; 11 May 2010 14:59:59 -0000 Received: (qmail 28561 invoked by uid 500); 11 May 2010 14:59:56 -0000 Delivered-To: apmail-hadoop-common-user-archive@hadoop.apache.org Received: (qmail 28394 invoked by uid 500); 11 May 2010 14:59:56 -0000 Mailing-List: contact common-user-help@hadoop.apache.org; run by ezmlm Precedence: bulk List-Help: List-Unsubscribe: List-Post: List-Id: Reply-To: common-user@hadoop.apache.org Delivered-To: mailing list common-user@hadoop.apache.org Received: (qmail 28386 invoked by uid 99); 11 May 2010 14:59:56 -0000 Received: from nike.apache.org (HELO nike.apache.org) (192.87.106.230) by apache.org (qpsmtpd/0.29) with ESMTP; Tue, 11 May 2010 14:59:56 +0000 X-ASF-Spam-Status: No, hits=0.0 required=10.0 tests=FREEMAIL_FROM,RCVD_IN_DNSWL_NONE,SPF_PASS,T_TO_NO_BRKTS_FREEMAIL X-Spam-Check-By: apache.org Received-SPF: pass (nike.apache.org: domain of owen.omalley@gmail.com designates 209.85.160.48 as permitted sender) Received: from [209.85.160.48] (HELO mail-pw0-f48.google.com) (209.85.160.48) by apache.org (qpsmtpd/0.29) with ESMTP; Tue, 11 May 2010 14:59:48 +0000 Received: by pwi6 with SMTP id 6so14747pwi.35 for ; Tue, 11 May 2010 07:59:27 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:mime-version:received:received:in-reply-to :references:date:message-id:subject:from:to:content-type; bh=Rg6LeZ5mplzsj2ZLbfeyJUKqp+wZXecyUdBAYnmZj94=; b=mlKafDcAR9KVFhqZA1RxYAz6KPC1nrDltXKfEQQhsprvWSuRiRTtH9wdWDIAJr7N/s mwmJovHCLymx1J2Hb2CXp26k0qabwHgg/oMuyxU5UCpdmRB5Smbnr7w7hYlnBKoy/WGF /gGI0CMKI99MUr9CSunqxT6sKSwfjfVcoiW3U= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :content-type; b=dA8wk60CtKjgUH+aE7BLrSOtS6YQg0n2FB0s54puvYL5TEKjFevq4JvDxawlUygOJR 1dFIsnyxyQb02QM8+DEzOhuQmo3bWnl7/sEVHm4r3YFnHkGws4EDLWpp/veM/StAgdpH JdaFFrI9w2DLfpsGqh/FHapn01SfD/jT9Z7Hw= MIME-Version: 1.0 Received: by 10.143.26.1 with SMTP id d1mr4021561wfj.311.1273589967165; Tue, 11 May 2010 07:59:27 -0700 (PDT) Received: by 10.142.233.8 with HTTP; Tue, 11 May 2010 07:59:26 -0700 (PDT) In-Reply-To: References: Date: Tue, 11 May 2010 07:59:26 -0700 Message-ID: Subject: Re: Questions about SequenceFiles From: "Owen O'Malley" To: common-user@hadoop.apache.org Content-Type: text/plain; charset=UTF-8 X-Virus-Checked: Checked by ClamAV on apache.org Assumption for Writables that should be documented somewhere: * Each type must have a 0 argument constructor. * Each call to write must not assume any shared state. * Each call to readFields must consume exactly the number of bytes produced by write. SequenceFile also assumes: * All keys are exactly the same type (not polymorphic). * All values are exactly the same type. * Both types are specified by the writer in the create call. -- Owen