Java Circular Reference - Can’t Compile

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By : Islam Ahmed

Date : November 28 2020, 08:01 AM

this one helps. File: A.java , They should compile fine if you compile them both at once:

code :

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Why does this generic constraint compile when it seems to have a circular reference

By : user2321695

Date : March 29 2020, 07:55 AM

hope this fix your issue UPDATE: This question was the basis of my blog article on the 3rd of February 2011. for the great question!

code :

abstract class Animal<T> where T : Animal<T>
{
    public abstract void MakeFriends(IEnumerable<T> newFriends);
}
class Cat : Animal<Cat>
{
    public override void MakeFriends(IEnumerable<Cat> newFriends) { ... }
}

class Tiger: Animal<Cat>
{
    public override void MakeFriends(IEnumerable<Cat> newFriends) { ... }
}

abstract class Animal 
{
    public abstract void MakeFriends(IEnumerable<THISTYPE> newFriends);
}

class Cat : Animal 
{
    public override void MakeFriends(IEnumerable<Cat> newFriends) {}
}

class Tiger: Animal
{
    // illegal!
    public override void MakeFriends(IEnumerable<Cat> newFriends) { ... }
}

Animal animal = new Cat();
animal.MakeFriends(new Animal[] {new Tiger()});

class SortedList<T> where T : IComparable<T>

class C<T, U> where T : U where U : T

Java Refactor led to a Circular reference

By : Harleymax

Date : March 29 2020, 07:55 AM

Hope this helps Check out this blog post on the topic; guice is smart enough, given the bindings you provide in your guice Module, to detect the circular reference and then use a temporary proxy so that the injection can be resolved.

Json and Java - Circular Reference

By : Temporary

Date : March 29 2020, 07:55 AM

wish of those help There are two ways you can go about this. If you must expose your entity to the outside world, I recommend adding @JsonIgnore on the property that is causing the circular reference. This will tell Jackson not to serialize that property.
Another way is to use the bidirectional features provided by Jackson. You can either use @JsonManagedReference or @JsonBackReference. @JsonManagedReference is the "forward" part of the property and it will get serialized normally. @JsonBackReference is the "back" part of the reference; it will not be serialized, but will be reconstructed when the "forward" type is deserialized.

Java - Enums - Logical circular reference

By : Nakul Bhojani

Date : March 29 2020, 07:55 AM

I think the issue was by ths following , You cannot assign SCISSORS to ROCK before it is defined. You can, instead, assign the values in a static block.
I have seen a lot examples where people use String values in the constructors, but this is more concrete to assign the actual values after they have been declared. This is encapsulated and the beats instance variable cannot be changed (unless you use reflection).

code :

public enum Hand {
    ROCK,
    PAPER,
    SCISSORS;

    private Hand beats;

    static {
        ROCK.beats = SCISSORS;
        PAPER.beats = ROCK;
        SCISSORS.beats = PAPER;
    }

    public Hand getBeats() {
        return beats;
    }

    public static void main(String[] args) {
        for (Hand hand : Hand.values()) {
            System.out.printf("%s beats %s%n", hand, hand.getBeats());
        }
    }
}

ROCK beats SCISSORS
PAPER beats ROCK
SCISSORS beats PAPER

Equivalent Java generic circular reference C#

By : user1718786

Date : March 29 2020, 07:55 AM

Any of those help What you see is not a circular reference. The type parameter constraint just lets you pass in a type which is a descendant of the generic type specified by the constraint.
The following code example compiles and I think will do what you need:

code :

public class UserAgentAnalyzerDirect { }

public class UserAgentAnalyzerDirectBuilder<UAA, B> 
    where UAA : UserAgentAnalyzerDirect 
    where B : UserAgentAnalyzerDirectBuilder<UAA, B>
{
    // this method is supposed to implement the effect of the 
    // constructor in the original Java code
    public void SetUAA(UAA a) { }

    // further implementation
}

public static UserAgentAnalyzerDirectBuilder<UAA, B> NewBuilder<UAA, B>()
    where UAA : UserAgentAnalyzerDirect, new()
    where B : UserAgentAnalyzerDirectBuilder<UAA, B>, new()
{
    // Unlike in Java, C# allows instantiating generic type parameters only using 
    // a parameter-less constructor. Hence we use the SetUAA method here instead.
    var a = new UAA();
    var b = new B();
    b.SetUAA(a);
    return b;
}

public class CustomUserAgentAnalyzerDirect : UserAgentAnalyzerDirect { }

public class CustomUserAgentAnalyzerDirectBuilder : UserAgentAnalyzerDirectBuilder<CustomUserAgentAnalyzerDirect, CustomUserAgentAnalyzerDirectBuilder> { }