I strongly support motion having difficulty running (Apache Kafka as opposed to Confluent) Stream examples with JDK 8 today. On 16 Jun 2016 4:46 p.m., "Ismael Juma" <ism...@juma.me.uk> wrote:
> Hi all, > > I would like to start a discussion on making Java 8 a minimum requirement > for Kafka's next feature release (let's say Kafka 0.10.1.0 for now). This > is the first discussion on the topic so the idea is to understand how > people feel about it. If people feel it's too soon, then we can pick up the > conversation again after Kafka 0.10.1.0. If the feedback is mostly > positive, I will start a vote thread. > > Let's start with some dates. Java 7 hasn't received public updates since > April 2015[1], Java 8 was released in March 2014[2] and Java 9 is scheduled > to be released in March 2017[3]. > > The first argument for dropping support for Java 7 is that the last public > release by Oracle contains a large number of known security > vulnerabilities. The effectiveness of Kafka's security features is reduced > if the underlying runtime is not itself secure. > > The second argument for moving to Java 8 is that it adds a number of > compelling features: > > * Lambda expressions and method references (particularly useful for the > Kafka Streams DSL) > * Default methods (very useful for maintaining compatibility when adding > methods to interfaces) > * java.util.stream (helpful for making collection transformations more > concise) > * Lots of improvements to java.util.concurrent (CompletableFuture, > DoubleAdder, DoubleAccumulator, StampedLock, LongAdder, LongAccumulator) > * Other nice things: SplittableRandom, Optional (and many others I have not > mentioned) > > The third argument is that it will simplify our testing matrix, we won't > have to test with Java 7 any longer (this is particularly useful for system > tests that take hours to run). It will also make it easier to support Scala > 2.12, which requires Java 8. > > The fourth argument is that many other open-source projects have taken the > leap already. Examples are Cassandra[4], Lucene[5], Akka[6], Hadoop 3[7], > Jetty[8], Eclipse[9], IntelliJ[10] and many others[11]. Even Android will > support Java 8 in the next version (although it will take a while before > most phones will use that version sadly). This reduces (but does not > eliminate) the chance that we would be the first project that would cause a > user to consider a Java upgrade. > > The main argument for not making the change is that a reasonable number of > users may still be using Java 7 by the time Kafka 0.10.1.0 is released. > More specifically, we care about the subset who would be able to upgrade to > Kafka 0.10.1.0, but would not be able to upgrade the Java version. It would > be great if we could quantify this in some way. > > What do you think? > > Ismael > > [1] https://java.com/en/download/faq/java_7.xml > [2] https://blogs.oracle.com/thejavatutorials/entry/jdk_8_is_released > [3] http://openjdk.java.net/projects/jdk9/ > [4] https://github.com/apache/cassandra/blob/trunk/README.asc > [5] https://lucene.apache.org/#highlights-of-this-lucene-release-include > [6] http://akka.io/news/2015/09/30/akka-2.4.0-released.html > [7] https://issues.apache.org/jira/browse/HADOOP-11858 > [8] https://webtide.com/jetty-9-3-features/ > [9] http://markmail.org/message/l7s276y3xkga2eqf > [10] > > https://intellij-support.jetbrains.com/hc/en-us/articles/206544879-Selecting-the-JDK-version-the-IDE-will-run-under > [11] http://markmail.org/message/l7s276y3xkga2eqf >
