collections

问题 I have a question or rather an issue with the JObject. This is just a small example, I have large lists with more than 20 elements and I am saving these in JSON format and it is really bad to read if every value is in a new line. Can someone explain to me how to fix this? Code: var myObj = new { Vector = new List<int>{ 1,2,3,4,5 } }; Console.WriteLine(JToken.FromObject(myObj).ToString(Formatting.Indented)); Output is like this: { "Vector": [ 1, 2, 3, 4, 5 ] } But I want it to be like this: {

问题 I have some Spring @Components with @Qualifier annotations, let's say it's in example "A" and "B". I want to inject them (using only annotations) into List. How can I do that ? @Component public class WhatIHave { @Autowired @Qualifier("A") private MyType firstBean; @Autowired @Qualifier("B") private MyType secondBean; .... } @Component public class WhatIWantToHave { @Autowired @Qualifier("A", "B") //something like that private List<MyType> beans; ... } Do I need to make it in @Configuration

问题 I'm creating MutableStateFlow like this: val intSet = MutableStateFlow(HashSet<Int>()) And in some moment later I want to update collection in this flow: intSet.value.add(0) And this doesn't seem to work (the collection updates, but observers are not notified). The way that I found it working: val list = HashSet<Int>(intSet.value) list.add(0) intSet.value = list But it creates copy of the collection, so it doesn't look proper for me. Is there any simpler way to update collection in StateFlow?

问题 I'm creating MutableStateFlow like this: val intSet = MutableStateFlow(HashSet<Int>()) And in some moment later I want to update collection in this flow: intSet.value.add(0) And this doesn't seem to work (the collection updates, but observers are not notified). The way that I found it working: val list = HashSet<Int>(intSet.value) list.add(0) intSet.value = list But it creates copy of the collection, so it doesn't look proper for me. Is there any simpler way to update collection in StateFlow?

问题 I could sort an array with respect to another if there is unique value. But since i am trying sort the below given array: initial fuel[]={1,9,9,2,9,9}; initial cost[]={2,6,5,4,3,1}; I wanted to sort fuel array then again wanted to sort cost array with respect to fuel array. I wanted output like given below: final fuel[]={1,2,9,9,9,9}; final cost[]={2,4,6,5,3,1}; Below is my code: public static void sort(List<Integer> c, List<Integer> f) { List<Integer> cc = new ArrayList<>(c); Collections

问题 Why is my collect Collectors.toList() showing this error: Expected 3 argument but found 1 package com.knoldus; import java.util.Arrays; import java.util.List; import java.util.stream.Collector; import java.util.stream.Collectors; import java.util.stream.IntStream; interface Cityeration<T> { public abstract List<T> Cityeration(List<T> first, List<T> Second); } public class ListMultiplication { public static void main(String s[]) { List firstList = Arrays.asList(1, 2, 3, 4, 5); List secondList

问题 Why is my collect Collectors.toList() showing this error: Expected 3 argument but found 1 package com.knoldus; import java.util.Arrays; import java.util.List; import java.util.stream.Collector; import java.util.stream.Collectors; import java.util.stream.IntStream; interface Cityeration<T> { public abstract List<T> Cityeration(List<T> first, List<T> Second); } public class ListMultiplication { public static void main(String s[]) { List firstList = Arrays.asList(1, 2, 3, 4, 5); List secondList

问题 Given any two classes, e.g. ClassA and ClassB below: class ClassA { private int intA; private String strA; private boolean boolA; // Constructor public ClassA (int intA, String strA, boolean boolA) { this.intA = intA; this.strA = strA; this.boolA = boolA; } // Getters and setters etc. below... } class ClassB { private int intB; private String strB; private boolean boolB; // Constructor public ClassB (int intB, String strB, boolean boolB) { this.intB = intB; this.strB = strB; this.boolB =

问题 Given any two classes, e.g. ClassA and ClassB below: class ClassA { private int intA; private String strA; private boolean boolA; // Constructor public ClassA (int intA, String strA, boolean boolA) { this.intA = intA; this.strA = strA; this.boolA = boolA; } // Getters and setters etc. below... } class ClassB { private int intB; private String strB; private boolean boolB; // Constructor public ClassB (int intB, String strB, boolean boolB) { this.intB = intB; this.strB = strB; this.boolB =

问题 What is the best way to drop a collection in MongoDB? I am using the following: db.collection.drop() As described in the manual: db.collection.drop() Removes a collection from the database. The method also removes any indexes associated with the dropped collection. The method provides a wrapper around the drop command. But how can I drop it from the command line? 回答1: So either of these are valid ways to do it: mongo <dbname> --eval 'db.<collection>.drop()' # ^^^^^^^^ ^^^^^^^^^^^^ db.