https://github.com/eclipse/eclipse-collections/eclipse-collections: Eclipse Collections is a collections framework for Java. It has JDK-compatible List, Set and Map implementations with a rich API and set of utility classes that work with any JDK compatible Collections, Arrays, Maps or Strings. The iteration protocol was inspired by the Smalltalk collection framework.
  • Craig P. Motlin
  • Donald Raab
  • Mohammad A. Rezaei
  • Hiroshi Ito
  • Nikhil J. Nanivadekar 
public final class org.eclipse.collections.impl.block.procedure.NonMutatingAggregationProcedure<T, K, V> implements org.eclipse.collections.api.block.procedure.Procedure<T>
  minor version: 0
  major version: 59
  flags: flags: (0x0031) ACC_PUBLIC, ACC_FINAL, ACC_SUPER
  this_class: org.eclipse.collections.impl.block.procedure.NonMutatingAggregationProcedure
  super_class: java.lang.Object
{
  private static final long serialVersionUID;
    descriptor: J
    flags: (0x001a) ACC_PRIVATE, ACC_STATIC, ACC_FINAL
    ConstantValue: 1

  private final org.eclipse.collections.api.map.MutableMap<K, V> map;
    descriptor: Lorg/eclipse/collections/api/map/MutableMap;
    flags: (0x0012) ACC_PRIVATE, ACC_FINAL
    Signature: Lorg/eclipse/collections/api/map/MutableMap<TK;TV;>;

  private final org.eclipse.collections.api.block.function.Function<? super T, ? extends K> groupBy;
    descriptor: Lorg/eclipse/collections/api/block/function/Function;
    flags: (0x0012) ACC_PRIVATE, ACC_FINAL
    Signature: Lorg/eclipse/collections/api/block/function/Function<-TT;+TK;>;

  private final org.eclipse.collections.api.block.function.Function0<? extends V> zeroValueFactory;
    descriptor: Lorg/eclipse/collections/api/block/function/Function0;
    flags: (0x0012) ACC_PRIVATE, ACC_FINAL
    Signature: Lorg/eclipse/collections/api/block/function/Function0<+TV;>;

  private final org.eclipse.collections.api.block.function.Function2<? super V, ? super T, ? extends V> nonMutatingAggregator;
    descriptor: Lorg/eclipse/collections/api/block/function/Function2;
    flags: (0x0012) ACC_PRIVATE, ACC_FINAL
    Signature: Lorg/eclipse/collections/api/block/function/Function2<-TV;-TT;+TV;>;

  public void <init>(org.eclipse.collections.api.map.MutableMap<K, V>, org.eclipse.collections.api.block.function.Function<? super T, ? extends K>, org.eclipse.collections.api.block.function.Function0<? extends V>, org.eclipse.collections.api.block.function.Function2<? super V, ? super T, ? extends V>);
    descriptor: (Lorg/eclipse/collections/api/map/MutableMap;Lorg/eclipse/collections/api/block/function/Function;Lorg/eclipse/collections/api/block/function/Function0;Lorg/eclipse/collections/api/block/function/Function2;)V
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=2, locals=5, args_size=5
        start local 0 // org.eclipse.collections.impl.block.procedure.NonMutatingAggregationProcedure this
        start local 1 // org.eclipse.collections.api.map.MutableMap map
        start local 2 // org.eclipse.collections.api.block.function.Function groupBy
        start local 3 // org.eclipse.collections.api.block.function.Function0 zeroValueFactory
        start local 4 // org.eclipse.collections.api.block.function.Function2 nonMutatingAggregator
         0: .line 32
            aload 0 /* this */
            invokespecial java.lang.Object.<init>:()V
         1: .line 34
            aload 0 /* this */
            aload 1 /* map */
            putfield org.eclipse.collections.impl.block.procedure.NonMutatingAggregationProcedure.map:Lorg/eclipse/collections/api/map/MutableMap;
         2: .line 35
            aload 0 /* this */
            aload 2 /* groupBy */
            putfield org.eclipse.collections.impl.block.procedure.NonMutatingAggregationProcedure.groupBy:Lorg/eclipse/collections/api/block/function/Function;
         3: .line 36
            aload 0 /* this */
            aload 3 /* zeroValueFactory */
            putfield org.eclipse.collections.impl.block.procedure.NonMutatingAggregationProcedure.zeroValueFactory:Lorg/eclipse/collections/api/block/function/Function0;
         4: .line 37
            aload 0 /* this */
            aload 4 /* nonMutatingAggregator */
            putfield org.eclipse.collections.impl.block.procedure.NonMutatingAggregationProcedure.nonMutatingAggregator:Lorg/eclipse/collections/api/block/function/Function2;
         5: .line 38
            return
        end local 4 // org.eclipse.collections.api.block.function.Function2 nonMutatingAggregator
        end local 3 // org.eclipse.collections.api.block.function.Function0 zeroValueFactory
        end local 2 // org.eclipse.collections.api.block.function.Function groupBy
        end local 1 // org.eclipse.collections.api.map.MutableMap map
        end local 0 // org.eclipse.collections.impl.block.procedure.NonMutatingAggregationProcedure this
      LocalVariableTable:
        Start  End  Slot                   Name  Signature
            0    6     0                   this  Lorg/eclipse/collections/impl/block/procedure/NonMutatingAggregationProcedure<TT;TK;TV;>;
            0    6     1                    map  Lorg/eclipse/collections/api/map/MutableMap<TK;TV;>;
            0    6     2                groupBy  Lorg/eclipse/collections/api/block/function/Function<-TT;+TK;>;
            0    6     3       zeroValueFactory  Lorg/eclipse/collections/api/block/function/Function0<+TV;>;
            0    6     4  nonMutatingAggregator  Lorg/eclipse/collections/api/block/function/Function2<-TV;-TT;+TV;>;
    Signature: (Lorg/eclipse/collections/api/map/MutableMap<TK;TV;>;Lorg/eclipse/collections/api/block/function/Function<-TT;+TK;>;Lorg/eclipse/collections/api/block/function/Function0<+TV;>;Lorg/eclipse/collections/api/block/function/Function2<-TV;-TT;+TV;>;)V
    MethodParameters:
                       Name  Flags
      map                    
      groupBy                
      zeroValueFactory       
      nonMutatingAggregator  

  public void value();
    descriptor: (Ljava/lang/Object;)V
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=5, locals=3, args_size=2
        start local 0 // org.eclipse.collections.impl.block.procedure.NonMutatingAggregationProcedure this
        start local 1 // java.lang.Object each
         0: .line 43
            aload 0 /* this */
            getfield org.eclipse.collections.impl.block.procedure.NonMutatingAggregationProcedure.groupBy:Lorg/eclipse/collections/api/block/function/Function;
            aload 1 /* each */
            invokeinterface org.eclipse.collections.api.block.function.Function.valueOf:(Ljava/lang/Object;)Ljava/lang/Object;
            astore 2 /* key */
        start local 2 // java.lang.Object key
         1: .line 44
            aload 0 /* this */
            getfield org.eclipse.collections.impl.block.procedure.NonMutatingAggregationProcedure.map:Lorg/eclipse/collections/api/map/MutableMap;
            aload 2 /* key */
            aload 0 /* this */
            getfield org.eclipse.collections.impl.block.procedure.NonMutatingAggregationProcedure.zeroValueFactory:Lorg/eclipse/collections/api/block/function/Function0;
            aload 0 /* this */
            getfield org.eclipse.collections.impl.block.procedure.NonMutatingAggregationProcedure.nonMutatingAggregator:Lorg/eclipse/collections/api/block/function/Function2;
            aload 1 /* each */
            invokeinterface org.eclipse.collections.api.map.MutableMap.updateValueWith:(Ljava/lang/Object;Lorg/eclipse/collections/api/block/function/Function0;Lorg/eclipse/collections/api/block/function/Function2;Ljava/lang/Object;)Ljava/lang/Object;
            pop
         2: .line 45
            return
        end local 2 // java.lang.Object key
        end local 1 // java.lang.Object each
        end local 0 // org.eclipse.collections.impl.block.procedure.NonMutatingAggregationProcedure this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    3     0  this  Lorg/eclipse/collections/impl/block/procedure/NonMutatingAggregationProcedure<TT;TK;TV;>;
            0    3     1  each  TT;
            1    3     2   key  TK;
    Signature: (TT;)V
    MethodParameters:
      Name  Flags
      each  
}
Signature: <T:Ljava/lang/Object;K:Ljava/lang/Object;V:Ljava/lang/Object;>Ljava/lang/Object;Lorg/eclipse/collections/api/block/procedure/Procedure<TT;>;
SourceFile: "NonMutatingAggregationProcedure.java"