[
https://issues.apache.org/jira/browse/HADOOP-15033?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16318949#comment-16318949
]
ASF GitHub Bot commented on HADOOP-15033:
-----------------------------------------
Github user steveloughran commented on a diff in the pull request:
https://github.com/apache/hadoop/pull/291#discussion_r160495383
--- Diff:
hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/util/Shell.java
---
@@ -86,7 +86,15 @@
*/
@Deprecated
public static boolean isJava7OrAbove() {
- return true;
+ return isJavaSpecAtLeast(7);
+ }
+
+ // "1.8"->8, "9"->9, "10"->10
+ private static final int JAVA_SPEC_VER = Math.max(8, Integer.parseInt(
+ System.getProperty("java.specification.version").split("\\.")[0]));
+
+ public static boolean isJavaSpecAtLeast(int version) {
--- End diff --
1. Can we call this `isJavaVersionAtLeast` ?
1. + javadoc explaining what it does
1. Needs a test in `TestShel` whichcalls the new API operation & sees that
it is consistent with its expectations (i.e on trunk it must be 8+)
> Use java.util.zip.CRC32C for Java 9 and above
> ---------------------------------------------
>
> Key: HADOOP-15033
> URL: https://issues.apache.org/jira/browse/HADOOP-15033
> Project: Hadoop Common
> Issue Type: Improvement
> Components: performance, util
> Affects Versions: 3.0.0
> Reporter: Dmitry Chuyko
> Labels: Java9, common, jdk9
> Attachments: HADOOP-15033.001.patch, HADOOP-15033.001.patch,
> HADOOP-15033.002.patch, HADOOP-15033.003.patch, HADOOP-15033.003.patch,
> HADOOP-15033.004.patch, HADOOP-15033.005.diff, HADOOP-15033.005.diff,
> HADOOP-15033.005.diff, HADOOP-15033.005.patch, HADOOP-15033.006.patch,
> HADOOP-15033.007.patch, HADOOP-15033.007.patch, HADOOP-15033.008.patch,
> HADOOP-15033.009.patch, HADOOP-15033.009.patch, HADOOP-15033.009.patch,
> HADOOP-15033.009.patch, HADOOP-15033.009.patch, HADOOP-15033.009.patch,
> HADOOP-15033.009.patch
>
>
> java.util.zip.CRC32C implementation is available since Java 9.
> https://docs.oracle.com/javase/9/docs/api/java/util/zip/CRC32C.html
> Platform specific assembler intrinsics make it more effective than any pure
> Java implementation.
> Hadoop is compiled against Java 8 but class constructor may be accessible
> with method handle on 9 to instances implementing Checksum in runtime.
--
This message was sent by Atlassian JIRA
(v6.4.14#64029)
---------------------------------------------------------------------
To unsubscribe, e-mail: common-issues-unsubscr...@hadoop.apache.org
For additional commands, e-mail: common-issues-h...@hadoop.apache.org
