Java
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Java – hibernate extra query after join fetch on the same entity
I try to query a large number of entities by using this query, although Hibernate: "Select * " + " From Dossie…… -
Java – get the POI Workbook of InputStream for OM Apache
Is there any way to get the InputStream of Apache POI workbook? I need it to pipe to another OutputStream, but I can't…… -
Java – Jackson captures unrecognized fields in the map
I use Jackson in Java rest API to handle request parameters My class: public class ZoneModifBeanParam extends ModifBea…… -
Java – the spring boot cannot parse placeholders in strings
I run spring boot on the embedded Tomcat server through Maven and MVN clean install spring boot: run But every time I …… -
Java – rewrite the same method twice from the same class
I understand how the iterator () method works with the ArrayList class In the ArrayList class, I found that the iterat…… -
Java – missing annotation handling menu in eclipse
I use this manual https://github.com/excilys/androidannotations/wiki/Eclipse-Only-Configuration "5 Go to Java Compiler…… -
Close, destructor and finalize: Java conflict
See English answers > why does a try / catch block create new variable scope? 5 try { FileInputStream in = new Fil…… -
External configurable filtering using java lambda
Suppose I have an external JSON: [{ "condition": "equals","field": "name","value": "jack" },{ "condition": "…… -
Java – Maven: exclude the “meta-inf / Maven” folder from the jar
I use Maven to build jars When I checked the jar, I saw a maven folder in the meta - inf folder I want it to be exclud…… -
String concatenation does not work in Java when concatenating two results of a ternary operator
Dear Java master! Please explain why concatenation does not work properly in Java when connecting two results of terna…… -
Java – programming the difference between POJOs and beans
I have the following two classes Can I say that the first is a POJO class and the second is a bean class? 1) POJO clas…… -
Why is the combiner function reduction operation not performed in the java-8 stream?
See English answers > java 8 stream – reduce function's combiner not getting executed Stream.of(1,2,3,4,5,6,7).redu…… -
Java – returns only the last element in the ArrayList
I've been teaching myself Java. I've always insisted on a problem. No matter what I do, it seems that I can't solve it…… -
Java – use groupingby for nested maps, but collect different types of objects
So I have the code for this "work" (replace some names for simplicity): Map<String,Map<String,ImmutableList<S…… -
How to use multiple streams and in Java 8 with lambda expressions Map function
I have a list County, which only contains the unique county name, and a list txcrarray, which contains the city name, …… -
Bean validation message with dynamic parameters
I started using bean validation, and I'm trying to build constraints My constraint is to verify CPF (personal file in …… -
Java – spring startup projects imported in IntelliJ do not work
I have imported the spring boot project generated by the spring boot initialiazr website, and I can't find the spring …… -
Java – ArrayList to array conversion – toarray() function infers that the type does not meet the upper limit error
This is the code simplet: Excel excel = new Excel(); ArrayList<Integer> a1=excel.readExcelSheet("C:\\Users\\Madh…… -
How to add classes that implement interfaces to ArrayList
In order to implement all methods in the interface, I created an abstract class that implements the interface, and the…… -
Java – why is there no exception in this byte?
I initialized a byte as follows: byte b = (byte) 0b11110000000; Since a byte is 8 bits in size, I expect it to throw s…… -
Lambda – the Java 8 stream is composed of three fields and aggregated by sum and count to produce single line output
I know that similar problems have been raised in the forum, but none of them seem to have completely solved my problem…… -
Java – array initializers are not allowed here
I have some model classes. I try to declare a list with them, but I get that the array initializer is not allowed here…… -
Java – cut and stack arrays
I have an int array as input The length of the array is always 2 ^ n. I want to cut the array in half and stack it Rep…… -
Java cucumber: obtain @ cucumber options from external sources, such as property files
Whether it can be from Java Get the cucumber option value from the properties file? In this so post, it shows that it …… -
Java – Convert list to map and filter null keys
Using the Java 8 stream, I want to convert the list into a map as described in the solution of Java 8 list < V >…… -
Java — call Runtime. in the onLowMemory method. gc()
Should we use runtime GC () or system GC () to clear the memory in the production code in the onlowmemory () method in…… -
Java Runtime. getRuntime(). Freememory() problem
I searched and saw some threads, but none solved the specific problem I encountered I tried to use runtime getRuntime(…… -
Using java to convert children to parent problems
class Parent { class Parent { int i = 60; } class Child extends Parent { int i = 70; } class Main { pub…… -
Java – how do I use group mapping streams?
I have a long child // ordered by parent.id / child.id Stream<Child> childStream; Say, Child(id = 1,parent(id = …… -
Java – how do I check that the value is equal to at least one field in the list?
I have this method: for (String fieldName : fieldArray) { Query query = new Query(); query.addCriteria…… -
Java – 25 even and even random number generator
I need to generate 25 random numbers and divide them into two arrays, depending on whether they are odd or even This i…… -
How do I scroll down to click an element in Android using appium and Java?
I wonder how to scroll down to click an element in Android using appium and Java? I have a list of elements in "Androi……