https://github.com/google/guava/guava: Guava is a suite of core and expanded libraries that include utility classes, google's collections, io classes, and much much more. 
public interface com.google.common.util.concurrent.CheckedFuture<V, X extends java.lang.Exception> extends com.google.common.util.concurrent.ListenableFuture<V>
  minor version: 0
  major version: 59
  flags: flags: (0x0601) ACC_PUBLIC, ACC_INTERFACE, ACC_ABSTRACT
  this_class: com.google.common.util.concurrent.CheckedFuture
  super_class: java.lang.Object
{
  public abstract V checkedGet() throws X;
    descriptor: ()Ljava/lang/Object;
    flags: (0x0401) ACC_PUBLIC, ACC_ABSTRACT
    Exceptions:
      throws java.lang.Exception
    Signature: ()TV;^TX;

  public abstract V checkedGet(long, java.util.concurrent.TimeUnit) throws java.util.concurrent.TimeoutException, X;
    descriptor: (JLjava/util/concurrent/TimeUnit;)Ljava/lang/Object;
    flags: (0x0401) ACC_PUBLIC, ACC_ABSTRACT
    Exceptions:
      throws java.util.concurrent.TimeoutException, java.lang.Exception
    Signature: (JLjava/util/concurrent/TimeUnit;)TV;^Ljava/util/concurrent/TimeoutException;^TX;
    MethodParameters:
         Name  Flags
      timeout  
      unit     
}
Signature: <V:Ljava/lang/Object;X:Ljava/lang/Exception;>Ljava/lang/Object;Lcom/google/common/util/concurrent/ListenableFuture<TV;>;
SourceFile: "CheckedFuture.java"
    RuntimeVisibleAnnotations: 
      java.lang.Deprecated()
    RuntimeInvisibleAnnotations: 
      com.google.common.annotations.Beta()
      com.google.errorprone.annotations.CanIgnoreReturnValue()
      com.google.common.annotations.GwtCompatible()