Java-7 | Source code for the Java 7 java | Build Tool library

Spark 1.6 / Java-7

Initial dataframe with a new column

I am trying to switch from java version java-8-openjdk-amd6 to java-11-openjdk-amd6 without using sudo since its not allowed.

i tried the following:

I have a simple snippet as below. I referred this

I need to derive an EC Public Key from an EC private key string without the "help" of any third party library.

The Private key is externally produced and provided and I need to get the Public Key to generate a Bitcoin address. As my project is working "offline" I do not need a library like Bouncy Castle for any other purpose, so I would like to eliminate it.

The following program is fully working and shows the (very short) example when working with Bouncy Castle to get a solution. The second part is the native Java solution with the kindly help from the routines by the so user SkateScout, for details see his answer https://stackoverflow.com/a/42797410/8166854.

Please keep in mind that this solution is working only for the Elliptic curve "secp256k1". You can check my keypair on https://gobittest.appspot.com/Address.

My question: is there any other solution available to avoid the mass of code for scalar operations?

I am trying to create a two dimensional list in java.

My first and preferred method is as so:

The code below takes about 15 seconds to generate a vector of 10k UUIDs. I will need to generate 1M or more and I calculate that this will take 15 * 10 * 10 / 60 minutes, or about 25 minutes. Is there a faster way to achieve this?

I have reactivated my dormant Amazon EC2 microinstance with Ubuntu 16.04.LTS and RStudio (see sessionInfo() output below) running (thanks to AMI by Louis Aslett). After ssh-ing to the AWS instance first I've run sudo apt-get update.

When I tried installing some packages (e.g xlsx and others) in R Studio (I've got an error because of missing Java, which seems to be a common problem). I followed advices to 1) install dependencies (for e.g. xlsx like rJava, and xlsxjars) separately; 2) apt-get install r-cran-rjava as suggested here. Then checking the installed java -version showed

openjdk version "1.8.0_131"
OpenJDK Runtime Environment (build 1.8.0_131-8u131-b11-0ubuntu1.16.04.2-b11)
OpenJDK 64-Bit Server VM (build 25.131-b11, mixed mode)

Similar problems were proposed "rJava load error in RStudio/R after “upgrading” to OSX Yosemite" and here "error: unable to load installed packages...", where the solution seemed to be linking the path of java to R export LD_LIBRARY_PATH=$JAVA_LD_LIBRARY_PATH or setting R's env. variables Sys.setenv(JAVA_HOME='/usr/lib/jvm/java-7-openjdk-amd64/jre/lib/amd64/server').

However, running R CMD javareconf -e revealed (I suppose) some deeper issues (see Image) &/or snippet:

I am having trouble understanding how precise rethrow works in Java 7 and later versions. As pointed out in https://www.theserverside.com/tutorial/OCPJP-Use-more-precise-rethrow-in-exceptions-Objective-Java-7, in Java 7 and later versions we can use the throws clause, in a method declaration, with a comma-separated list of specific exceptions that the method could throw. If all these exceptions are subtypes of the general exception java.lang.Exception, we will be able to catch any of them in a catch block that catches this supertype, while letting client code (eg. a caller method) to know which of the possible subtypes exceptions actually occurred.

Initially, I thought that in order to let know client code which exception actually occurred, we needed to specify the list of specific exceptions in the throws clause. Nevertheless, in the following example the client code (the main() method) seems able to retrieve that information, even if we only specify the exception java.lang.Exception in the throws clause of the called method. Therefore, my question is:

Why the following code outputs the same, regardless of whether the throws clause of the method runException() is throws ExceptionA, ExceptionB or throws Exception ?

I am using Oracle JVM-12 in Eclipse. Thanks in advance!

I'm posting this as a possible bug report because this page says,

Troubleshooting

Please report any issues on our StackOverflow page: https://stackoverflow.com/questions/tagged/corda

Maybe these instructions for installing Java on Ubuntu are wrong (obsolete):

https://docs.corda.net/getting-set-up.html#id4

Java

1. Open a new terminal and add the Oracle PPA to your repositories by typing sudo add-apt-repository ppa:webupd8team/java. Press ENTER when prompted.
2. Update your packages list with the command sudo apt update
3. Install the Oracle JDK 8 by typing sudo apt install oracle-java8-installer.
4. Press Y when prompted and agree to the licence terms.

Because what I see when I do that is as follows: