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Java 12

jdk.java.net

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Re: Java 12

#11

Post by melling »

_old_dude_ wrote: post #8
azhenley wrote: post #5

Earlier quoted context omitted.

In case someone is curious what it looks like with the new -> form: switch (day) { case MONDAY, FRIDAY, SUNDAY -> System.out.println(6); case TUESDAY -> System.out.println(7); case THURSDAY, SATURDAY -> System.out.println(8); case WEDNESDAY -> System.out.println(9); }

or using the switch as an expression System.out.println(switch(day) { case MONDAY, FRIDAY, SUNDAY -> 6; case TUESDAY -> 7; case THURSDAY, SATURDAY -> 8; case WEDNESDAY -> 9; });

That's much nicer. Anything else added to Java recently to reduce the boilerplate? I haven't used Java much in 5-6 years. Glad they are iterating faster.

Re: Java 12

#12

Post by ars »

crooked-v wrote: post #4

Still nothing to handle checked exceptions in streams properly... sigh.

Or in FunctionalInterface, or in anonymous functions.

Makes HashMap computeIfAbsent much less useful than it should be. It's impossible to use a function in there that throws a checked exception (all I want is for the exception to propagate out of computeIfAbsent for the parent method to deal with).

Best option I've found is to wrap it in an unchecked exception, then unwrap it in the parent method, which is just .... yuck.

Re: Java 12

#14

Post by ars »

_old_dude_ wrote: post #8
azhenley wrote: post #5

Earlier quoted context omitted.

In case someone is curious what it looks like with the new -> form: switch (day) { case MONDAY, FRIDAY, SUNDAY -> System.out.println(6); case TUESDAY -> System.out.println(7); case THURSDAY, SATURDAY -> System.out.println(8); case WEDNESDAY -> System.out.println(9); }

or using the switch as an expression System.out.println(switch(day) { case MONDAY, FRIDAY, SUNDAY -> 6; case TUESDAY -> 7; case THURSDAY, SATURDAY -> 8; case WEDNESDAY -> 9; });

I assume the expression becomes null if none of those match?

Re: Java 12

#16

Post by ocdtrekkie »

Meanwhile, most enterprise apps still seem to only work with JRE 8. And those which I know of have elected to replace Java rather than upgrade.

Re: Java 12

#17

Post by jason0597 »

darksaints wrote: post #10

Anybody know how the graal project ties in with all of this? Is oracle effectively developing 3 different JVMs (OpenJDK, Oracle JDK, GraalVM)? Or is there some sort of convergence plan? From what I understand, graal has made a lot of headway with language interop, as well as a handful of specific memory optimizations and native compilation, but overall is lagging in pure throughput/latency performance behind hotspot.…

Well the relationship between OpenJDK and Oracle JDK is that OpenJDK is the FOSS base and Oracle JDK is the proprietary structure built on top, kinda like Chromium and Chrome

As for GraalVM, I don't think it's meant to be mixed in with those 2 at all. From their website (https://www.graalvm.org/), it sounds to me as if it's a completely different project that shares none of the goals the other 2 JDKs have:

> GraalVM is a universal virtual machine for running applications written in JavaScript, Python, Ruby, R, JVM-based languages like Java, Scala, Kotlin, Clojure, and LLVM-based languages such as C and C++.

> GraalVM removes the isolation between programming languages and enables interoperability in a shared runtime. It can run either standalone or in the context of OpenJDK, Node.js, Oracle Database, or MySQL.

Re: Java 12

#18

Post by _old_dude_ »

ars wrote: post #14
_old_dude_ wrote: post #8

Earlier quoted context omitted.

or using the switch as an expression System.out.println(switch(day) { case MONDAY, FRIDAY, SUNDAY -> 6; case TUESDAY -> 7; case THURSDAY, SATURDAY -> 8; case WEDNESDAY -> 9; });

I assume the expression becomes null if none of those match?

No my bad, it doesn't compile, you have to add a default.

Re: Java 12

#19

Post by pbz »

ocdtrekkie wrote: post #16

Meanwhile, most enterprise apps still seem to only work with JRE 8. And those which I know of have elected to replace Java rather than upgrade.

What are they replacing it with?

Re: Java 12

#20

Post by vbezhenar »

crooked-v wrote: post #4

Still nothing to handle checked exceptions in streams properly... sigh.

I wonder why they didn't use generic exception type in their java.util.function classes. That would propagate checked exceptions statically.

Something like

  @FunctionalInterface
  interface Function {
      R apply(T t) throws E;
  }
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