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Java – how to improve on this function (Java 8 streams)

I’ve coded a function that finds the unique characters in a string using Java 8 streams, based on an example here. To me, it’s pretty non-intuitive, maybe because I’m still learning streams. Is there any way to make this more readable? Here’s the code: Answer For calculating the actual frequencies, you’re pretty much at a minimal example already! And for

Why is my maven build not finding Netty’s EventLoopGroup class when executing?

I wrote my code following Netty’s documentation, then I execute: It builds successfully. Then I run: And it promts me with this error: Exception in thread “main” java.lang.NoClassDefFoundError: io/netty/channel/EventLoopGroup at java.lang.Class.getDeclaredMethods0(Native Method) at java.lang.Class.privateGetDeclaredMethods(Class.java:2701) at java.lang.Class.privateGetMethodRecursive(Class.java:3048) at java.lang.Class.getMethod0(Class.java:3018) at java.lang.Class.getMethod(Class.java:1784) at sun.launcher.LauncherHelper.validateMainClass(LauncherHelper.java:544) at sun.launcher.LauncherHelper.checkAndLoadMain(LauncherHelper.java:526) Caused by: java.lang.ClassNotFoundException: io.netty.channel.EventLoopGroup at java.net.URLClassLoader.findClass(URLClassLoader.java:381) at java.lang.ClassLoader.loadClass(ClassLoader.java:424) at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:331) at java.lang.ClassLoader.loadClass(ClassLoader.java:357) … 7 more To

To open file in Java/jena API

Hi I’m currently learning semantic web on java and Jena API. I have an error to open a file which is in the same directory with my class My code : The error : Exception in thread “main” java.lang.IllegalArgumentException: File: vc-db-1.rdf not found NB : The file is in the same directory Answer Already resolved by static final String inputFileName

hibernate validator throws exception ValidationException: HV000028 for @Past annotation

I am validating an entity with a hibernate validator in a spring boot project. I got an exception for the Date validator @Past . I faced javax.validation.ValidationException: HV000028: Unexpected exception during isValid call This is the dependency I have in my gradle.build file implementation ‘org.springframework.boot:spring-boot-starter-validation’ The following my a similar entity I have This is a log trace Answer This

Adjust classpath / change spring version in azure databricks

I’m trying to use Apache Spark/Ignite integration in Azure Databricks. I install the org.apache.ignite:ignite-spark-2.4:2.9.0 maven library using the Databricks UI. And I have an error while accessing my ignite cahces: Here the AbstractApplicationContext is compiled with ReflectionUtils of different spring version. I see the spring-core-4.3.26.RELEASE.jar is installed in the /dbfs/FileStore/jars/maven/org/springframework during the org.apache.ignite:ignite-spark-2.4:2.9.0 installation and there are no other spring

The numbers never occur next to each other

I wrote a program that reads an array of integers and two numbers n and m. The program check that n and m never occur next to each other (in any order) in the array. Test input: Correct output: true My output is blank. What am I doing wrong? Answer Your code will throw ArrayIndexOutOfBoundsException as you are using array[j+1]

FilterRegistrationBean url pattern doesn’t work

I am registering a filter as shown below For log output i want url pattern : /*/api/* Answer Since the code registers a Servlet Filter, the URL pattern must conform to the URL mappings supported by Servlets/Filters, as specified in the Servlet Specification: 12.2 Specification of Mappings In the Web application deployment descriptor, the following syntax is used to define

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