Mailing-List: contact dev-help@accumulo.apache.org; run by ezmlm
Precedence: bulk
Reply-To: dev@accumulo.apache.org
From: keith-turner <git@git.apache.org>
To: dev@accumulo.apache.org
Reply-To: dev@accumulo.apache.org
References: <git-pr-168-accumulo@git.apache.org>
In-Reply-To: <git-pr-168-accumulo@git.apache.org>
Subject: [GitHub] accumulo pull request #168: ACCUMULO-4501 (work in progress) Very simple imp...
Content-Type: text/plain
Message-Id: <20161017124549.84EB1DFDEC@git1-us-west.apache.org>
Date: Mon, 17 Oct 2016 12:45:49 +0000 (UTC)
archived-at: Mon, 17 Oct 2016 12:45:52 -0000

Github user keith-turner commented on a diff in the pull request:

    https://github.com/apache/accumulo/pull/168#discussion_r83634090
  
    --- Diff: core/src/main/java/org/apache/accumulo/core/file/rfile/histogram/VisibilityHistogramLocalityGroupWriter.java ---
    @@ -0,0 +1,62 @@
    +/*
    + * Licensed to the Apache Software Foundation (ASF) under one or more
    + * contributor license agreements.  See the NOTICE file distributed with
    + * this work for additional information regarding copyright ownership.
    + * The ASF licenses this file to you under the Apache License, Version 2.0
    + * (the "License"); you may not use this file except in compliance with
    + * the License.  You may obtain a copy of the License at
    + *
    + * http://www.apache.org/licenses/LICENSE-2.0
    + *
    + * Unless required by applicable law or agreed to in writing, software
    + * distributed under the License is distributed on an "AS IS" BASIS,
    + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    + * See the License for the specific language governing permissions and
    + * limitations under the License.
    + */
    +package org.apache.accumulo.core.file.rfile.histogram;
    +
    +import java.io.IOException;
    +import java.util.HashMap;
    +import java.util.concurrent.atomic.AtomicLong;
    +
    +import org.apache.accumulo.core.data.Key;
    +import org.apache.accumulo.core.data.Value;
    +import org.apache.accumulo.core.file.rfile.RFile.LocalityGroupWriter;
    +import org.apache.hadoop.io.Text;
    +
    +/**
    + * 
    + */
    +public class VisibilityHistogramLocalityGroupWriter {
    +  private final HashMap<Text,AtomicLong> histogram;
    +  private final LocalityGroupWriter lgr;
    +
    +  private ThreadLocal<Text> buffer = new ThreadLocal<Text>() {
    +    @Override public Text initialValue() {
    +      return new Text();
    +    }
    +  };
    +
    +  public VisibilityHistogramLocalityGroupWriter(LocalityGroupWriter lgr) {
    +    this.lgr = lgr;
    +    this.histogram = new HashMap<>(); 
    +  }
    +
    +  public void append(Key key, Value value) throws IOException {
    +    Text _text = buffer.get();
    +    key.getColumnVisibility(_text);
    +    AtomicLong count = histogram.get(_text);
    --- End diff --
    
    I think this could use the ByteSequence returned by getColumnVisibilityData() to do the lookup in the map (would require keying map on ByteSequence).  This would avoid the copy for lookup.   Only copy when inserting into the map. 


---
If your project is set up for it, you can reply to this email and have your
reply appear on GitHub as well. If your project does not have this feature
enabled and wishes so, or if the feature is enabled but not working, please
contact infrastructure at infrastructure@apache.org or file a JIRA ticket
with INFRA.
---