Java
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How to handle exceptions in Java 8 stream?
I have a method. I traverse the list and create the list In doing so, I call a method (createresult) to throw a custom…… -
Java – instantiate ArrayList by reading rows from scanner, where to declare objects?
I want to fill the array list with lines from the input file, which is as follows: 7f000000000000000000000000000000000…… -
Java – play location service getlastlocation returns null
I'm trying to listen to location changes, but sometimes the onlocationchanged callback is never called, getlastlocatio…… -
Java – querydsl does not use spring boot and Maven to generate Q classes
I don't know why, but I can't use spring boot and query DSL to generate query classes This is my POM xml： <propert…… -
Java – horizontal recycler view with left and right arrow indicators
I'm trying to use the left and right arrow indicators to achieve a horizontal loop view So what happens is that if you…… -
Java – if first is true, it is logical or the second statement is ignored
See English answers > java logical operator short circuiting 9 Solution No, No >Using the Boolean operator |, if…… -
Java – hibernate condition groups start with timestamp by date
I have a table with a timestamp column and want to create a hibernate conditional projection. The results are grouped …… -
Java – compile a multi module Maven project without installing it into a local repository
There is a compilation (and packaging) problem in my multi module Maven project There was a problem compiling one of t…… -
Java – throw exceptions in finally and catch blocks
There is a problem with the exception thrown in catch. Finally, stop: class MyExc1 extends Exception {} class MyExc2 e…… -
Java – improve code that breaks down faster?
I want to finish this code faster It returns all the factors (prime) of a long number If longnumber is specific, it ob…… -
java – AlarmManager. AlarmClockinfo. Getnextalarmclock() caused NullPointerException
problem When I try to use AlarmManager The alarmclockinfo object getnextalarmclock() is thrown by my application: tryi…… -
Will JavaFX alert truncate messages?
See English answers > JavaFX alerts and their size 4 Example: import javafx.application.Application; import javafx.…… -
Java – exceptions in Google guava eventbus and event handlers
The guava eventbus documentation illustrates this If you know that some exceptions may occur, you can register the sub…… -
Java – how to delete firebase data after “n” days
I want to delete some old data in my friedbase I know this question has been asked a lot here, but it is still difficu…… -
Java – how to resolve jar conflicts at run time?
I have two jars in conflict They all contain a class with the same package name and class name For the same reason, I …… -
Java – dynamodbmapppingexception: mapping without hash key
When writing dynamodb Java application, if the table and its data model are not configured correctly, you can receive …… -
Java – stream mapping to find the value of the latest key
I have a map < < element, attributes >, which consists of the following (example) classes and instances of en…… -
Java – “unable to parse the symbol ‘request’ of Facebook graph API” error
I will the latest Facebook SDK 4.0 1 is included in the Android studio project I want to make the basic graph API call…… -
When they are Is java integer always = = when equals()?
See English answer > java: integer equals vs. = = 5 Integer x = 5; Integer y = x + 1; Integer z = y - 1; x.equals(z…… -
Get errors in C using vector and struct
What is the error in this Code: #include <iostream> #include <vector> #include <algorithm> using nam…… -
Java – ‘CMD’ is not recognized as an internal or external command and can run programs or batch files
When I build my project in NetBeans, it shows: 'cmd' is not recognized as an internal or external command,operable pro…… -
Is java “public static void main (string [] args)” the only way to create a main method?
I wonder if "Java main method" is the only way to create a main method in Java Java main methods: Solution The JVM nee…… -
What does Java – compareto() actually return?
The CompareTo () method in Java returns a value greater than / equal to / less than 0 But value itself is my problem W…… -
Java – hashcode contract that maintains specific conditions, and equals () depends on two integers
I have a basic structure class: class Employee { int eId; String eName; Employee(int id,String name) { this.eId= …… -
java – Stream. Is findany a short circuit operation?
Consider this code Object found = collection.stream() .filter( s -> myPredicate1(s)) .filter( s -> myPre…… -
Rxjava in scheduler IO () does not work in the thread
The problem is: I have observable and subscriber I'm trying Start observable in the IO () thread because it applies to…… -
Set boolean flag in Java 8 stream
I wonder what is the best practice for setting boolean flag values from Java streams Here is an example I want to do: …… -
Java – how to correctly throw a NullPointerException?
I need to write a method delete (), which accepts an int parameter K and deletes the k-th element in the linked list (…… -
When using java 8 update101, HashMap Entries cannot be cast to collection
After updating to Java 8 update 101, I encountered an exception in the following code It works well with Java 8 update…… -
How to effectively convert java code to Python?
I would be glad if you could tell me how to translate code from Java to python Solution If you want to translate java …… -
Java – insert different arrays in ArrayList
I inserted an array in ArrayList, but after inserting the second array, the first array is the same as the second arra…… -
Why doesn’t my java exchange function work?
See English answer > is java "pass by reference" or "pass by value"? 78 void swap(int a,int b) { int temp = a; ……