Java
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Convert an existing c# synchronous method to asynchronous using async / await?
Starting with the synchronous I / O binding method (shown below), how do I use async / await to make it asynchronous? …… -
java – android. support. v7. app. ActionBarImplICS. Getthemedcontext NullPointerException in Android
Please help me get Java lang.NullPointerException java.lang.NullPointerException at android.support.v7.app.ActionBarIm…… -
Java – eclipse / ant creates a jar in version 1.9, even if everything seems to be set to 1.8
I have a project built using ant and eclipse, and I want it to be compatible with Java 8 When I try to run jar using j…… -
Java – where does Maven search for log4j Properties file?
I am using log4j with Maven to face problems I have a properties file, log4j Properties, I put this file in the POM. N…… -
Java 8: default method for automatically synthesizing multiple interfaces
I have classes that implement multiple interfaces with the same default methods I want to know how to synthesize defau…… -
Java – spring: you cannot connect to JMX server from behind the firewall using RMI
My spring application runs on the machine behind the NAT firewall (pfsense) The internal IP of the machine is a.b.c.d …… -
How do I provide an implementation for enumeration values in Java?
I have the value of the enumeration class. Assuming that it will grow over time, I hope the user adding the new enumer…… -
Java – why does the clear HashMap method clear the map added in the array list
I'm trying to reuse the same HashMap, such as the following example to populate the list First, I add some values to t…… -
Java – how to use reduce only to find the minimum value in the list?
I want to use reduce only to find the minimum value in list < integer > This is my original idea: List<Intege…… -
Asynchronous – f# asynchronous workflow / task combined with free Monad
I'm trying to build a pipeline for message processing using the free monad pattern. My code looks like this: module Pi…… -
Constructor: final double in Java
I can't understand why the double XX and YY are placed last in the constructor Why don't I double them XX and double Y…… -
Java: triple curl support
I received some comment codes, unlike any code I've encountered before: //{{{ Imports import imports; //}}} Each metho…… -
How does Java 8 add custom elements to a collection?
Is there a Java 8 mode to perform the following operations? for(int i;i<=100;i++){ Person person=new Person(); …… -
Java – if the else statement has four results, but only two seem to work
So I'm studying my first project on programming Never tried any programming I want it to be able to choose between fou…… -
Java – why does changing an object in an ArrayList change it in all other ArrayLists?
I'm making a CPU scheduling simulator (for school projects) There is a problem with my roundrobin function When I do c…… -
Invoking non abstract methods in abstract class java
I have three classes This seems to be a basic problem But I can't find the answer through Google search public abstrac…… -
RX Java – share() and publish() What is the difference between autoconnect()?
In my opinion I thinkhare () and release () Autoconnect () is the same But in this code, the result is different Obser…… -
How do I resize JavaFX images?
I have a JavaFX scene. image. Image, I want to resize it, for example, scale it by a given factor What to do (not conv…… -
A better way to use Java 8
I convert the following code into Java 8 code I wonder if I'm doing it right or if there are other good ways Java 7 fo…… -
java – ！ list. Isempty() and list Size () > 0, same conditions?
I see such code if (!substanceList.isEmpty() && (substanceList.size() > 0)) { substanceText = createAmoun…… -
Java – display integers on toast
I tried to display a toast message with an integer in it Toast.makeText(this,bignum,Toast.LENGTH_LONG).show(); But it …… -
Java – why does kotlin use = = for structural equality and introduce = = = for reference equality
In general, every design decision made by kotlin feels great in itself and provides a good java transition As a java d…… -
Java – can I create a file in my S3 lambda function?
I am creating a Java function for AWS lambda, which imports a file from AWS S3, as shown below: InputStream videoObjec…… -
Java 8 – how do I copy attribute values from one list to another?
I have two lists, for example: List<Foo> list1 = Lists.newArrayList(new Foo(...),...); List<Bar> list2 = L…… -
Java – define new variables
I'm a novice in Java programming. I met something I don't quite understand: if (Object.getSomething() != null) { …… -
Java – how to use recursion to check whether all values in an array are equal?
I try to solve this algorithm recursively; I want to check that all values in the array are the same (or equal to each…… -
Java ternary compared with large objects
Ternary operators are usually just a topic of philosophical discussion: a=b>5?1:0; More readable, faster, cooler if…… -
Java interrupts or exits a thread
I have a thread that performs several different tasks Each task depends on the success of the previous task If this is…… -
Inheriting a class without a parent type in Java
How do I inherit from other classes without using a parent type? For example, I hope that car can adopt all methods an…… -
Java chess: not sure how to clone correctly
I am writing a basic java chess game and have written the following classes: game, player, chessboard, square, pieces …… -
How do I convert UTC date strings and delete T and Z in Java?
I am using java 1.7 Attempt to convert: 2018-05-23T23:18:31.000Z become 2018-05-23 23:18:31 Dateutils class: public cl…… -
Is it correct to infer that the default method is used in the interface to make it like an abstract class in Java?
Since we now have default methods in the interface, is it more like an abstract class using both abstract and non abst……