http://fastutil.di.unimi.it/: fastutil extends the Java Collections Framework by providing type-specific maps, sets, lists and priority queues with a small memory footprint and fast access and insertion; provides also big (64-bit) arrays, sets and lists, and fast, practical I/O classes for binary and text files.
  • Sebastiano Vigna 
public interface it.unimi.dsi.fastutil.PriorityQueue<K>
  minor version: 0
  major version: 59
  flags: flags: (0x0601) ACC_PUBLIC, ACC_INTERFACE, ACC_ABSTRACT
  this_class: it.unimi.dsi.fastutil.PriorityQueue
  super_class: java.lang.Object
{
  public abstract void enqueue();
    descriptor: (Ljava/lang/Object;)V
    flags: (0x0401) ACC_PUBLIC, ACC_ABSTRACT
    Signature: (TK;)V
    MethodParameters:
      Name  Flags
      x     

  public abstract K dequeue();
    descriptor: ()Ljava/lang/Object;
    flags: (0x0401) ACC_PUBLIC, ACC_ABSTRACT
    Signature: ()TK;

  public boolean isEmpty();
    descriptor: ()Z
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=1, locals=1, args_size=1
        start local 0 // it.unimi.dsi.fastutil.PriorityQueue this
         0: .line 64
            aload 0 /* this */
            invokeinterface it.unimi.dsi.fastutil.PriorityQueue.size:()I
            ifne 1
            iconst_1
            ireturn
      StackMap locals:
      StackMap stack:
         1: iconst_0
            ireturn
        end local 0 // it.unimi.dsi.fastutil.PriorityQueue this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    2     0  this  Lit/unimi/dsi/fastutil/PriorityQueue<TK;>;

  public abstract int size();
    descriptor: ()I
    flags: (0x0401) ACC_PUBLIC, ACC_ABSTRACT

  public abstract void clear();
    descriptor: ()V
    flags: (0x0401) ACC_PUBLIC, ACC_ABSTRACT

  public abstract K first();
    descriptor: ()Ljava/lang/Object;
    flags: (0x0401) ACC_PUBLIC, ACC_ABSTRACT
    Signature: ()TK;

  public K last();
    descriptor: ()Ljava/lang/Object;
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=2, locals=1, args_size=1
        start local 0 // it.unimi.dsi.fastutil.PriorityQueue this
         0: .line 94
            new java.lang.UnsupportedOperationException
            dup
            invokespecial java.lang.UnsupportedOperationException.<init>:()V
            athrow
        end local 0 // it.unimi.dsi.fastutil.PriorityQueue this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    1     0  this  Lit/unimi/dsi/fastutil/PriorityQueue<TK;>;
    Signature: ()TK;

  public void changed();
    descriptor: ()V
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=2, locals=1, args_size=1
        start local 0 // it.unimi.dsi.fastutil.PriorityQueue this
         0: .line 100
            new java.lang.UnsupportedOperationException
            dup
            invokespecial java.lang.UnsupportedOperationException.<init>:()V
            athrow
        end local 0 // it.unimi.dsi.fastutil.PriorityQueue this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    1     0  this  Lit/unimi/dsi/fastutil/PriorityQueue<TK;>;

  public abstract java.util.Comparator<? super K> comparator();
    descriptor: ()Ljava/util/Comparator;
    flags: (0x0401) ACC_PUBLIC, ACC_ABSTRACT
    Signature: ()Ljava/util/Comparator<-TK;>;
}
Signature: <K:Ljava/lang/Object;>Ljava/lang/Object;
SourceFile: "PriorityQueue.java"