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POText.getBytes() returns unexpected results
 

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    <p>I'm getting some behavior from the Text constructors that don't really make any sense. Basically, if I construct a Text object from a String, it is not equal to another Text object that I constructed from bytes, even though getBytes() returns the same value for both objects. </p> <p>So we get weird stuff like this :</p> <pre><code>//This succeeds assertEquals(new Text("ACTACGACCA_0"), new Text("ACTACGACCA_0")); //This succeeds assertEquals((new Text("ACTACGACCA_0")).getBytes(), (new Text("ACTACGACCA_0")).getBytes()); //This fails. Why? assertEquals(new Text((new Text("ACTACGACCA_0")).getBytes()), new Text("ACTACGACCA_0")); </code></pre> <p>This manifests when I'm trying to access a hashmap. Here, I'm trying to do a lookup based on a value returned by org.apache.hadoop.hbase.KeyValue.getRow() :</p> <pre><code>//This succeeds assertEquals((new Text("ACTACGACCA_0")).getBytes(), keyValue.getRow()); //This returns a value hashMap.get(new Text("ACTACGACCA_0")); //This returns null. Why? hashMap.get(new Text(keyValue.getRow())); </code></pre> <p>So what's going on here, and how do I deal with it? Does this have something to do with encoding?</p> <h2>UPDATE : PROBLEM SOLVED</h2> <p>Thanks to Chris for pointing me in the right direction with this. So, a little background : the keyValue object is captured (using a Mockito ArgumentCaptor) from a call to htable.put(). Basically, I had this chunk of code :</p> <pre><code>byte[] keyBytes = matchRow.getKey().getBytes(); RowLock rowLock = hTable.lockRow(keyBytes); Get get = new Get(keyBytes, rowLock); SetWritable&lt;Text&gt; toWrite = new SetWritable&lt;Text&gt;(Text.class); toWrite.getValues().addAll(matchRow.getMatches(hTable, get)); Put put = new Put(keyBytes, rowLock); put.add(Bytes.toBytes(MatchesByHaplotype.MATCHING_COLUMN_FAMILY), Bytes.toBytes(MatchesByHaplotype.UID_QUALIFIER), SERIALIZATION_HELPER.serialize(toWrite)); hTable.put(put); </code></pre> <p>where matchRow.getKey() returns a text object. You see the problem here? I was adding all the bytes, <strong>including the invalid ones.</strong> So I created a nice helper function that does this :</p> <pre><code>public byte[] getValidBytes(Text text) { return Arrays.copyOf(text.getBytes(), text.getLength()); } </code></pre> <p>And changed the first line of that block to this :</p> <pre><code>byte[] keyBytes = SERIALIZATION_HELPER.getValidBytes(matchRow.getKey()); </code></pre> <p>Problem solved! In retrospect : wow, what a nasty bug! I think what it comes down to is that the behavior of Text.getBytes() is very n00b-unfriendly. Not only does it return something that you may not expect (non-valid bytes), the Text object doesn't have a function to return only the valid bytes! You would think this would be a common use-case. Maybe they'll add this in the future?</p>
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