Why is this an issue?

According to the Java Code Conventions as defined by Oracle, the members of a class or interface declaration should appear in the following order in the source files:

Noncompliant code example

public class Foo{
   private int field = 0;
   public boolean isTrue() {...}
   public Foo() {...}                         // Noncompliant, constructor defined after methods
   public static final int OPEN = 4;  //Noncompliant, variable defined after constructors and methods
}

Compliant solution

public class Foo{
   public static final int OPEN = 4;
   private int field = 0;
   public Foo() {...}
   public boolean isTrue() {...}
}