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 class org.eclipse.collections.impl.map.immutable.primitive.ImmutableIntDoubleHashMap$ImmutableIntDoubleMapSerializationProxy implements java.io.Externalizable
  minor version: 0
  major version: 59
  flags: flags: (0x0021) ACC_PUBLIC, ACC_SUPER
  this_class: org.eclipse.collections.impl.map.immutable.primitive.ImmutableIntDoubleHashMap$ImmutableIntDoubleMapSerializationProxy
  super_class: java.lang.Object
{
  private static final long serialVersionUID;
    descriptor: J
    flags: (0x001a) ACC_PRIVATE, ACC_STATIC, ACC_FINAL
    ConstantValue: 1

  private org.eclipse.collections.api.map.primitive.IntDoubleMap map;
    descriptor: Lorg/eclipse/collections/api/map/primitive/IntDoubleMap;
    flags: (0x0002) ACC_PRIVATE

  public void <init>();
    descriptor: ()V
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=1, locals=1, args_size=1
        start local 0 // org.eclipse.collections.impl.map.immutable.primitive.ImmutableIntDoubleHashMap$ImmutableIntDoubleMapSerializationProxy this
         0: .line 501
            aload 0 /* this */
            invokespecial java.lang.Object.<init>:()V
         1: .line 504
            return
        end local 0 // org.eclipse.collections.impl.map.immutable.primitive.ImmutableIntDoubleHashMap$ImmutableIntDoubleMapSerializationProxy this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    2     0  this  Lorg/eclipse/collections/impl/map/immutable/primitive/ImmutableIntDoubleHashMap$ImmutableIntDoubleMapSerializationProxy;

  protected void <init>(org.eclipse.collections.api.map.primitive.IntDoubleMap);
    descriptor: (Lorg/eclipse/collections/api/map/primitive/IntDoubleMap;)V
    flags: (0x0004) ACC_PROTECTED
    Code:
      stack=2, locals=2, args_size=2
        start local 0 // org.eclipse.collections.impl.map.immutable.primitive.ImmutableIntDoubleHashMap$ImmutableIntDoubleMapSerializationProxy this
        start local 1 // org.eclipse.collections.api.map.primitive.IntDoubleMap map
         0: .line 506
            aload 0 /* this */
            invokespecial java.lang.Object.<init>:()V
         1: .line 508
            aload 0 /* this */
            aload 1 /* map */
            putfield org.eclipse.collections.impl.map.immutable.primitive.ImmutableIntDoubleHashMap$ImmutableIntDoubleMapSerializationProxy.map:Lorg/eclipse/collections/api/map/primitive/IntDoubleMap;
         2: .line 509
            return
        end local 1 // org.eclipse.collections.api.map.primitive.IntDoubleMap map
        end local 0 // org.eclipse.collections.impl.map.immutable.primitive.ImmutableIntDoubleHashMap$ImmutableIntDoubleMapSerializationProxy this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    3     0  this  Lorg/eclipse/collections/impl/map/immutable/primitive/ImmutableIntDoubleHashMap$ImmutableIntDoubleMapSerializationProxy;
            0    3     1   map  Lorg/eclipse/collections/api/map/primitive/IntDoubleMap;
    MethodParameters:
      Name  Flags
      map   

  public void writeExternal(java.io.ObjectOutput);
    descriptor: (Ljava/io/ObjectOutput;)V
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=5, locals=3, args_size=2
        start local 0 // org.eclipse.collections.impl.map.immutable.primitive.ImmutableIntDoubleHashMap$ImmutableIntDoubleMapSerializationProxy this
        start local 1 // java.io.ObjectOutput out
         0: .line 514
            aload 1 /* out */
            aload 0 /* this */
            getfield org.eclipse.collections.impl.map.immutable.primitive.ImmutableIntDoubleHashMap$ImmutableIntDoubleMapSerializationProxy.map:Lorg/eclipse/collections/api/map/primitive/IntDoubleMap;
            invokeinterface org.eclipse.collections.api.map.primitive.IntDoubleMap.size:()I
            invokeinterface java.io.ObjectOutput.writeInt:(I)V
         1: .line 517
            aload 0 /* this */
            getfield org.eclipse.collections.impl.map.immutable.primitive.ImmutableIntDoubleHashMap$ImmutableIntDoubleMapSerializationProxy.map:Lorg/eclipse/collections/api/map/primitive/IntDoubleMap;
            new org.eclipse.collections.impl.map.immutable.primitive.ImmutableIntDoubleHashMap$ImmutableIntDoubleMapSerializationProxy$1
            dup
            aload 0 /* this */
            aload 1 /* out */
            invokespecial org.eclipse.collections.impl.map.immutable.primitive.ImmutableIntDoubleHashMap$ImmutableIntDoubleMapSerializationProxy$1.<init>:(Lorg/eclipse/collections/impl/map/immutable/primitive/ImmutableIntDoubleHashMap$ImmutableIntDoubleMapSerializationProxy;Ljava/io/ObjectOutput;)V
            invokeinterface org.eclipse.collections.api.map.primitive.IntDoubleMap.forEachKeyValue:(Lorg/eclipse/collections/api/block/procedure/primitive/IntDoubleProcedure;)V
         2: .line 526
            goto 7
         3: .line 527
      StackMap locals:
      StackMap stack: java.lang.RuntimeException
            astore 2 /* e */
        start local 2 // java.lang.RuntimeException e
         4: .line 529
            aload 2 /* e */
            invokevirtual java.lang.RuntimeException.getCause:()Ljava/lang/Throwable;
            instanceof java.io.IOException
            ifeq 6
         5: .line 531
            aload 2 /* e */
            invokevirtual java.lang.RuntimeException.getCause:()Ljava/lang/Throwable;
            checkcast java.io.IOException
            athrow
         6: .line 533
      StackMap locals: java.lang.RuntimeException
      StackMap stack:
            aload 2 /* e */
            athrow
        end local 2 // java.lang.RuntimeException e
         7: .line 535
      StackMap locals:
      StackMap stack:
            return
        end local 1 // java.io.ObjectOutput out
        end local 0 // org.eclipse.collections.impl.map.immutable.primitive.ImmutableIntDoubleHashMap$ImmutableIntDoubleMapSerializationProxy this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    8     0  this  Lorg/eclipse/collections/impl/map/immutable/primitive/ImmutableIntDoubleHashMap$ImmutableIntDoubleMapSerializationProxy;
            0    8     1   out  Ljava/io/ObjectOutput;
            4    7     2     e  Ljava/lang/RuntimeException;
      Exception table:
        from    to  target  type
           1     2       3  Class java.lang.RuntimeException
    Exceptions:
      throws java.io.IOException
    MethodParameters:
      Name  Flags
      out   final

  public void readExternal(java.io.ObjectInput);
    descriptor: (Ljava/io/ObjectInput;)V
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=4, locals=5, args_size=2
        start local 0 // org.eclipse.collections.impl.map.immutable.primitive.ImmutableIntDoubleHashMap$ImmutableIntDoubleMapSerializationProxy this
        start local 1 // java.io.ObjectInput in
         0: .line 540
            aload 1 /* in */
            invokeinterface java.io.ObjectInput.readInt:()I
            istore 2 /* size */
        start local 2 // int size
         1: .line 541
            new org.eclipse.collections.impl.map.mutable.primitive.IntDoubleHashMap
            dup
            invokespecial org.eclipse.collections.impl.map.mutable.primitive.IntDoubleHashMap.<init>:()V
            astore 3 /* deserializedMap */
        start local 3 // org.eclipse.collections.api.map.primitive.MutableIntDoubleMap deserializedMap
         2: .line 543
            iconst_0
            istore 4 /* i */
        start local 4 // int i
         3: goto 6
         4: .line 545
      StackMap locals: int org.eclipse.collections.api.map.primitive.MutableIntDoubleMap int
      StackMap stack:
            aload 3 /* deserializedMap */
            aload 1 /* in */
            invokeinterface java.io.ObjectInput.readInt:()I
            aload 1 /* in */
            invokeinterface java.io.ObjectInput.readDouble:()D
            invokeinterface org.eclipse.collections.api.map.primitive.MutableIntDoubleMap.put:(ID)V
         5: .line 543
            iinc 4 /* i */ 1
      StackMap locals:
      StackMap stack:
         6: iload 4 /* i */
            iload 2 /* size */
            if_icmplt 4
        end local 4 // int i
         7: .line 548
            aload 0 /* this */
            aload 3 /* deserializedMap */
            putfield org.eclipse.collections.impl.map.immutable.primitive.ImmutableIntDoubleHashMap$ImmutableIntDoubleMapSerializationProxy.map:Lorg/eclipse/collections/api/map/primitive/IntDoubleMap;
         8: .line 549
            return
        end local 3 // org.eclipse.collections.api.map.primitive.MutableIntDoubleMap deserializedMap
        end local 2 // int size
        end local 1 // java.io.ObjectInput in
        end local 0 // org.eclipse.collections.impl.map.immutable.primitive.ImmutableIntDoubleHashMap$ImmutableIntDoubleMapSerializationProxy this
      LocalVariableTable:
        Start  End  Slot             Name  Signature
            0    9     0             this  Lorg/eclipse/collections/impl/map/immutable/primitive/ImmutableIntDoubleHashMap$ImmutableIntDoubleMapSerializationProxy;
            0    9     1               in  Ljava/io/ObjectInput;
            1    9     2             size  I
            2    9     3  deserializedMap  Lorg/eclipse/collections/api/map/primitive/MutableIntDoubleMap;
            3    7     4                i  I
    Exceptions:
      throws java.io.IOException, java.lang.ClassNotFoundException
    MethodParameters:
      Name  Flags
      in    

  protected java.lang.Object readResolve();
    descriptor: ()Ljava/lang/Object;
    flags: (0x0004) ACC_PROTECTED
    Code:
      stack=1, locals=1, args_size=1
        start local 0 // org.eclipse.collections.impl.map.immutable.primitive.ImmutableIntDoubleHashMap$ImmutableIntDoubleMapSerializationProxy this
         0: .line 553
            aload 0 /* this */
            getfield org.eclipse.collections.impl.map.immutable.primitive.ImmutableIntDoubleHashMap$ImmutableIntDoubleMapSerializationProxy.map:Lorg/eclipse/collections/api/map/primitive/IntDoubleMap;
            invokeinterface org.eclipse.collections.api.map.primitive.IntDoubleMap.toImmutable:()Lorg/eclipse/collections/api/map/primitive/ImmutableIntDoubleMap;
            areturn
        end local 0 // org.eclipse.collections.impl.map.immutable.primitive.ImmutableIntDoubleHashMap$ImmutableIntDoubleMapSerializationProxy this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    1     0  this  Lorg/eclipse/collections/impl/map/immutable/primitive/ImmutableIntDoubleHashMap$ImmutableIntDoubleMapSerializationProxy;
}
SourceFile: "ImmutableIntDoubleHashMap.java"
NestHost: org.eclipse.collections.impl.map.immutable.primitive.ImmutableIntDoubleHashMap
InnerClasses:
  protected ImmutableIntDoubleMapSerializationProxy = org.eclipse.collections.impl.map.immutable.primitive.ImmutableIntDoubleHashMap$ImmutableIntDoubleMapSerializationProxy of org.eclipse.collections.impl.map.immutable.primitive.ImmutableIntDoubleHashMap
  org.eclipse.collections.impl.map.immutable.primitive.ImmutableIntDoubleHashMap$ImmutableIntDoubleMapSerializationProxy$1