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. 
class com.google.common.base.Predicates$InPredicate<T> implements com.google.common.base.Predicate<T>, java.io.Serializable
  minor version: 0
  major version: 59
  flags: flags: (0x0020) ACC_SUPER
  this_class: com.google.common.base.Predicates$InPredicate
  super_class: java.lang.Object
{
  private final java.util.Collection<?> target;
    descriptor: Ljava/util/Collection;
    flags: (0x0012) ACC_PRIVATE, ACC_FINAL
    Signature: Ljava/util/Collection<*>;

  private static final long serialVersionUID;
    descriptor: J
    flags: (0x001a) ACC_PRIVATE, ACC_STATIC, ACC_FINAL
    ConstantValue: 0

  private void <init>(java.util.Collection<?>);
    descriptor: (Ljava/util/Collection;)V
    flags: (0x0002) ACC_PRIVATE
    Code:
      stack=2, locals=2, args_size=2
        start local 0 // com.google.common.base.Predicates$InPredicate this
        start local 1 // java.util.Collection target
         0: .line 549
            aload 0 /* this */
            invokespecial java.lang.Object.<init>:()V
         1: .line 550
            aload 0 /* this */
            aload 1 /* target */
            invokestatic com.google.common.base.Preconditions.checkNotNull:(Ljava/lang/Object;)Ljava/lang/Object;
            checkcast java.util.Collection
            putfield com.google.common.base.Predicates$InPredicate.target:Ljava/util/Collection;
         2: .line 551
            return
        end local 1 // java.util.Collection target
        end local 0 // com.google.common.base.Predicates$InPredicate this
      LocalVariableTable:
        Start  End  Slot    Name  Signature
            0    3     0    this  Lcom/google/common/base/Predicates$InPredicate<TT;>;
            0    3     1  target  Ljava/util/Collection<*>;
    Signature: (Ljava/util/Collection<*>;)V
    MethodParameters:
        Name  Flags
      target  

  public boolean apply();
    descriptor: (Ljava/lang/Object;)Z
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=2, locals=2, args_size=2
        start local 0 // com.google.common.base.Predicates$InPredicate this
        start local 1 // java.lang.Object t
         0: .line 556
            aload 0 /* this */
            getfield com.google.common.base.Predicates$InPredicate.target:Ljava/util/Collection;
            aload 1 /* t */
            invokeinterface java.util.Collection.contains:(Ljava/lang/Object;)Z
         1: ireturn
         2: .line 557
      StackMap locals:
      StackMap stack: java.lang.RuntimeException
            pop
         3: .line 558
            iconst_0
            ireturn
        end local 1 // java.lang.Object t
        end local 0 // com.google.common.base.Predicates$InPredicate this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    4     0  this  Lcom/google/common/base/Predicates$InPredicate<TT;>;
            0    4     1     t  TT;
      Exception table:
        from    to  target  type
           0     1       2  Class java.lang.NullPointerException
           0     1       2  Class java.lang.ClassCastException
    Signature: (TT;)Z
    RuntimeVisibleTypeAnnotations: 
      METHOD_FORMAL_PARAMETER
        org.checkerframework.checker.nullness.qual.Nullable()
    MethodParameters:
      Name  Flags
      t     

  public boolean equals(java.lang.Object);
    descriptor: (Ljava/lang/Object;)Z
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=2, locals=3, args_size=2
        start local 0 // com.google.common.base.Predicates$InPredicate this
        start local 1 // java.lang.Object obj
         0: .line 564
            aload 1 /* obj */
            instanceof com.google.common.base.Predicates$InPredicate
            ifeq 3
         1: .line 565
            aload 1 /* obj */
            checkcast com.google.common.base.Predicates$InPredicate
            astore 2 /* that */
        start local 2 // com.google.common.base.Predicates$InPredicate that
         2: .line 566
            aload 0 /* this */
            getfield com.google.common.base.Predicates$InPredicate.target:Ljava/util/Collection;
            aload 2 /* that */
            getfield com.google.common.base.Predicates$InPredicate.target:Ljava/util/Collection;
            invokeinterface java.util.Collection.equals:(Ljava/lang/Object;)Z
            ireturn
        end local 2 // com.google.common.base.Predicates$InPredicate that
         3: .line 568
      StackMap locals:
      StackMap stack:
            iconst_0
            ireturn
        end local 1 // java.lang.Object obj
        end local 0 // com.google.common.base.Predicates$InPredicate this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    4     0  this  Lcom/google/common/base/Predicates$InPredicate<TT;>;
            0    4     1   obj  Ljava/lang/Object;
            2    3     2  that  Lcom/google/common/base/Predicates$InPredicate<*>;
    RuntimeVisibleTypeAnnotations: 
      METHOD_FORMAL_PARAMETER
        org.checkerframework.checker.nullness.qual.Nullable()
    MethodParameters:
      Name  Flags
      obj   

  public int hashCode();
    descriptor: ()I
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=1, locals=1, args_size=1
        start local 0 // com.google.common.base.Predicates$InPredicate this
         0: .line 573
            aload 0 /* this */
            getfield com.google.common.base.Predicates$InPredicate.target:Ljava/util/Collection;
            invokeinterface java.util.Collection.hashCode:()I
            ireturn
        end local 0 // com.google.common.base.Predicates$InPredicate this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    1     0  this  Lcom/google/common/base/Predicates$InPredicate<TT;>;

  public java.lang.String toString();
    descriptor: ()Ljava/lang/String;
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=3, locals=1, args_size=1
        start local 0 // com.google.common.base.Predicates$InPredicate this
         0: .line 578
            new java.lang.StringBuilder
            dup
            ldc "Predicates.in("
            invokespecial java.lang.StringBuilder.<init>:(Ljava/lang/String;)V
            aload 0 /* this */
            getfield com.google.common.base.Predicates$InPredicate.target:Ljava/util/Collection;
            invokevirtual java.lang.StringBuilder.append:(Ljava/lang/Object;)Ljava/lang/StringBuilder;
            ldc ")"
            invokevirtual java.lang.StringBuilder.append:(Ljava/lang/String;)Ljava/lang/StringBuilder;
            invokevirtual java.lang.StringBuilder.toString:()Ljava/lang/String;
            areturn
        end local 0 // com.google.common.base.Predicates$InPredicate this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    1     0  this  Lcom/google/common/base/Predicates$InPredicate<TT;>;
}
Signature: <T:Ljava/lang/Object;>Ljava/lang/Object;Lcom/google/common/base/Predicate<TT;>;Ljava/io/Serializable;
SourceFile: "Predicates.java"
NestHost: com.google.common.base.Predicates
InnerClasses:
  private InPredicate = com.google.common.base.Predicates$InPredicate of com.google.common.base.Predicates