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.io.BaseEncoding$3 extends java.io.Reader
  minor version: 0
  major version: 59
  flags: flags: (0x0020) ACC_SUPER
  this_class: com.google.common.io.BaseEncoding$3
  super_class: java.io.Reader
{
  private final java.io.Reader val$delegate;
    descriptor: Ljava/io/Reader;
    flags: (0x1012) ACC_PRIVATE, ACC_FINAL, ACC_SYNTHETIC

  private final java.lang.String val$toIgnore;
    descriptor: Ljava/lang/String;
    flags: (0x1012) ACC_PRIVATE, ACC_FINAL, ACC_SYNTHETIC

  void <init>(java.io.Reader, java.lang.String);
    descriptor: (Ljava/io/Reader;Ljava/lang/String;)V
    flags: (0x0000) 
    Code:
      stack=2, locals=3, args_size=3
        start local 0 // com.google.common.io.BaseEncoding$3 this
         0: .line 978
            aload 0 /* this */
            aload 1
            putfield com.google.common.io.BaseEncoding$3.val$delegate:Ljava/io/Reader;
            aload 0 /* this */
            aload 2
            putfield com.google.common.io.BaseEncoding$3.val$toIgnore:Ljava/lang/String;
            aload 0 /* this */
            invokespecial java.io.Reader.<init>:()V
            return
        end local 0 // com.google.common.io.BaseEncoding$3 this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    1     0  this  Lcom/google/common/io/BaseEncoding$3;
    MethodParameters:
              Name  Flags
      val$delegate  final
      val$toIgnore  final

  public int read();
    descriptor: ()I
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=2, locals=2, args_size=1
        start local 0 // com.google.common.io.BaseEncoding$3 this
         0: .line 983
      StackMap locals:
      StackMap stack:
            aload 0 /* this */
            getfield com.google.common.io.BaseEncoding$3.val$delegate:Ljava/io/Reader;
            invokevirtual java.io.Reader.read:()I
            istore 1 /* readChar */
        start local 1 // int readChar
         1: .line 984
            iload 1 /* readChar */
            iconst_m1
            if_icmpeq 3
            aload 0 /* this */
            getfield com.google.common.io.BaseEncoding$3.val$toIgnore:Ljava/lang/String;
            iload 1 /* readChar */
            i2c
            invokevirtual java.lang.String.indexOf:(I)I
         2: .line 982
            ifge 0
         3: .line 985
      StackMap locals: int
      StackMap stack:
            iload 1 /* readChar */
            ireturn
        end local 1 // int readChar
        end local 0 // com.google.common.io.BaseEncoding$3 this
      LocalVariableTable:
        Start  End  Slot      Name  Signature
            0    4     0      this  Lcom/google/common/io/BaseEncoding$3;
            1    4     1  readChar  I
    Exceptions:
      throws java.io.IOException

  public int read(char[], int, int);
    descriptor: ([CII)I
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=2, locals=4, args_size=4
        start local 0 // com.google.common.io.BaseEncoding$3 this
        start local 1 // char[] cbuf
        start local 2 // int off
        start local 3 // int len
         0: .line 990
            new java.lang.UnsupportedOperationException
            dup
            invokespecial java.lang.UnsupportedOperationException.<init>:()V
            athrow
        end local 3 // int len
        end local 2 // int off
        end local 1 // char[] cbuf
        end local 0 // com.google.common.io.BaseEncoding$3 this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    1     0  this  Lcom/google/common/io/BaseEncoding$3;
            0    1     1  cbuf  [C
            0    1     2   off  I
            0    1     3   len  I
    Exceptions:
      throws java.io.IOException
    MethodParameters:
      Name  Flags
      cbuf  
      off   
      len   

  public void close();
    descriptor: ()V
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=1, locals=1, args_size=1
        start local 0 // com.google.common.io.BaseEncoding$3 this
         0: .line 995
            aload 0 /* this */
            getfield com.google.common.io.BaseEncoding$3.val$delegate:Ljava/io/Reader;
            invokevirtual java.io.Reader.close:()V
         1: .line 996
            return
        end local 0 // com.google.common.io.BaseEncoding$3 this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    2     0  this  Lcom/google/common/io/BaseEncoding$3;
    Exceptions:
      throws java.io.IOException
}
SourceFile: "BaseEncoding.java"
EnclosingMethod: com.google.common.io.BaseEncoding.ignoringReader:(Ljava/io/Reader;Ljava/lang/String;)Ljava/io/Reader;
NestHost: com.google.common.io.BaseEncoding
InnerClasses:
  com.google.common.io.BaseEncoding$3