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https://issues.apache.org/jira/browse/HBASE-10771?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13965067#comment-13965067
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Matt Corgan commented on HBASE-10771:
-------------------------------------
taking a look at patch_2 after a mention in HBASE-10861
{code}Pair<Long, Integer> getVLong(int index) throws IOException{code}this
returns a fairly heavyweight object. maybe it should just return a primitive
long and we could have a public static method "int numVLongBytes(long n)" that
quickly computes the number of bytes. here is a different VLong format i wrote
a while back. i don't know what the numBytes formula for this particular VLong
would be, but you can see how efficiently it could possibly be calculated.
probably much cheaper than creating 3 objects
{code}
public static int numBytes(long in){// do a check for illegal arguments
if not protected
if(in == 0){ return 1; }// doesn't work with the formula below
return (70 - Long.numberOfLeadingZeros(in)) / 7;// 70 comes
from 64+(7-1)
}
public static byte[] getBytes(long value){
int numBytes = numBytes(value);
byte[] bytes = new byte[numBytes];
long remainder = value;
for(int i = 0; i < numBytes - 1; ++i){
bytes[i] = (byte)((remainder & LONG_7_RIGHT_BITS_SET) |
LONG_8TH_BIT_SET);// set the left bit
remainder >>= 7;
}
bytes[numBytes - 1] = (byte)(remainder &
LONG_7_RIGHT_BITS_SET);// do not set the left bit
return bytes;
}
{code}
also not sure the checked IOException is necessary since all of these methods
could encounter similar corruption errors, plus the actual IO has presumably
already been done earlier.
{code}
+ @Override
+ public long getLong(int index) {
+ return Bytes.toLong(bytes, index);
+ }
{code}
does the hbase Bytes util have the exact same format that ByteBuffers use?
native java format can be seen in java.nio.Bits.java
> Primitive type put/get APIs in ByteRange
> -----------------------------------------
>
> Key: HBASE-10771
> URL: https://issues.apache.org/jira/browse/HBASE-10771
> Project: HBase
> Issue Type: Improvement
> Reporter: Anoop Sam John
> Assignee: Anoop Sam John
> Fix For: 0.99.0
>
> Attachments: HBASE-10771.patch, HBASE-10771_V2.patch
>
>
> While doing HBASE-10713 I came across the need to write int/long (and read
> also) from a ByteRange. CellBlocks are backed by ByteRange. So we can add
> such APIs.
> Also as per HBASE-10750 we return a ByteRange from MSLAB and also discussion
> under HBASE-10191 suggest we can have BR backed HFileBlocks etc.
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