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import java.lang.reflect.InvocationHandler;
import java.lang.reflect.Method;
import java.lang.reflect.Proxy;
 
public class Main {
 
    interface Foo { }
 
    interface Bar { }
 
    static class FooBar1 implements Foo, Bar {
        public String toString() {
            return "FooBar1";
        }
    }
 
    static class FooBar2 implements Foo, Bar {
        public String toString() {
            return "FooBar2";
        }
    }
 
 
 
    static <T extends Foo & Bar> T getFooBar1() {
        return (T) new FooBar1();
    }
 
    static <T extends Foo & Bar> T getFooBar2() {
        return (T) new FooBar2();
    }
 
    static <T extends Foo & Bar> T getFooBar() {
        return (T) Proxy.newProxyInstance(
                Foo.class.getClassLoader(),
                new Class<?>[] {Foo.class, Bar.class},
                new InvocationHandler() {
                    public Object invoke(Object proxy, Method method, Object[] args) {
                        return "PROXY!!!";
                    }
                }
        );
    }
 
    static <U extends Foo & Bar> void show(U u) {
        System.out.println(u);
    }
 
    public static void main(String[] args) {
        show(getFooBar());
        show(getFooBar1());
        show(getFooBar2());
    }
}

Main.java:50: type parameters of <T>T cannot be determined; no unique maximal instance exists for type variable T with upper bounds java.lang.Object,Main.Foo,Main.Bar
        show(getFooBar());
                      ^
Main.java:51: type parameters of <T>T cannot be determined; no unique maximal instance exists for type variable T with upper bounds java.lang.Object,Main.Foo,Main.Bar
        show(getFooBar1());
                       ^
Main.java:52: type parameters of <T>T cannot be determined; no unique maximal instance exists for type variable T with upper bounds java.lang.Object,Main.Foo,Main.Bar
        show(getFooBar2());
                       ^
Note: Main.java uses unchecked or unsafe operations.
Note: Recompile with -Xlint:unchecked for details.
3 errors

Standard output is empty