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. 
final class com.google.common.base.Platform
  minor version: 0
  major version: 59
  flags: flags: (0x0030) ACC_FINAL, ACC_SUPER
  this_class: com.google.common.base.Platform
  super_class: java.lang.Object
{
  private static final java.util.logging.Logger logger;
    descriptor: Ljava/util/logging/Logger;
    flags: (0x001a) ACC_PRIVATE, ACC_STATIC, ACC_FINAL

  private static final com.google.common.base.PatternCompiler patternCompiler;
    descriptor: Lcom/google/common/base/PatternCompiler;
    flags: (0x001a) ACC_PRIVATE, ACC_STATIC, ACC_FINAL

  static void <clinit>();
    descriptor: ()V
    flags: (0x0008) ACC_STATIC
    Code:
      stack=1, locals=0, args_size=0
         0: .line 33
            ldc Lcom/google/common/base/Platform;
            invokevirtual java.lang.Class.getName:()Ljava/lang/String;
            invokestatic java.util.logging.Logger.getLogger:(Ljava/lang/String;)Ljava/util/logging/Logger;
            putstatic com.google.common.base.Platform.logger:Ljava/util/logging/Logger;
         1: .line 34
            invokestatic com.google.common.base.Platform.loadPatternCompiler:()Lcom/google/common/base/PatternCompiler;
            putstatic com.google.common.base.Platform.patternCompiler:Lcom/google/common/base/PatternCompiler;
            return
      LocalVariableTable:
        Start  End  Slot  Name  Signature

  private void <init>();
    descriptor: ()V
    flags: (0x0002) ACC_PRIVATE
    Code:
      stack=1, locals=1, args_size=1
        start local 0 // com.google.common.base.Platform this
         0: .line 36
            aload 0 /* this */
            invokespecial java.lang.Object.<init>:()V
            return
        end local 0 // com.google.common.base.Platform this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    1     0  this  Lcom/google/common/base/Platform;

  static long systemNanoTime();
    descriptor: ()J
    flags: (0x0008) ACC_STATIC
    Code:
      stack=2, locals=0, args_size=0
         0: .line 41
            invokestatic java.lang.System.nanoTime:()J
            lreturn
      LocalVariableTable:
        Start  End  Slot  Name  Signature

  static com.google.common.base.CharMatcher precomputeCharMatcher(com.google.common.base.CharMatcher);
    descriptor: (Lcom/google/common/base/CharMatcher;)Lcom/google/common/base/CharMatcher;
    flags: (0x0008) ACC_STATIC
    Code:
      stack=1, locals=1, args_size=1
        start local 0 // com.google.common.base.CharMatcher matcher
         0: .line 45
            aload 0 /* matcher */
            invokevirtual com.google.common.base.CharMatcher.precomputedInternal:()Lcom/google/common/base/CharMatcher;
            areturn
        end local 0 // com.google.common.base.CharMatcher matcher
      LocalVariableTable:
        Start  End  Slot     Name  Signature
            0    1     0  matcher  Lcom/google/common/base/CharMatcher;
    MethodParameters:
         Name  Flags
      matcher  

  static <T extends java.lang.Enum<T>> com.google.common.base.Optional<T> getEnumIfPresent(java.lang.Class<T>, java.lang.String);
    descriptor: (Ljava/lang/Class;Ljava/lang/String;)Lcom/google/common/base/Optional;
    flags: (0x0008) ACC_STATIC
    Code:
      stack=2, locals=3, args_size=2
        start local 0 // java.lang.Class enumClass
        start local 1 // java.lang.String value
         0: .line 49
            aload 0 /* enumClass */
            invokestatic com.google.common.base.Enums.getEnumConstants:(Ljava/lang/Class;)Ljava/util/Map;
            aload 1 /* value */
            invokeinterface java.util.Map.get:(Ljava/lang/Object;)Ljava/lang/Object;
            checkcast java.lang.ref.WeakReference
            astore 2 /* ref */
        start local 2 // java.lang.ref.WeakReference ref
         1: .line 50
            aload 2 /* ref */
            ifnonnull 2
            invokestatic com.google.common.base.Optional.absent:()Lcom/google/common/base/Optional;
            goto 3
      StackMap locals: java.lang.ref.WeakReference
      StackMap stack:
         2: aload 0 /* enumClass */
            aload 2 /* ref */
            invokevirtual java.lang.ref.WeakReference.get:()Ljava/lang/Object;
            invokevirtual java.lang.Class.cast:(Ljava/lang/Object;)Ljava/lang/Object;
            checkcast java.lang.Enum
            invokestatic com.google.common.base.Optional.of:(Ljava/lang/Object;)Lcom/google/common/base/Optional;
      StackMap locals:
      StackMap stack: com.google.common.base.Optional
         3: areturn
        end local 2 // java.lang.ref.WeakReference ref
        end local 1 // java.lang.String value
        end local 0 // java.lang.Class enumClass
      LocalVariableTable:
        Start  End  Slot       Name  Signature
            0    4     0  enumClass  Ljava/lang/Class<TT;>;
            0    4     1      value  Ljava/lang/String;
            1    4     2        ref  Ljava/lang/ref/WeakReference<+Ljava/lang/Enum<*>;>;
    Signature: <T:Ljava/lang/Enum<TT;>;>(Ljava/lang/Class<TT;>;Ljava/lang/String;)Lcom/google/common/base/Optional<TT;>;
    MethodParameters:
           Name  Flags
      enumClass  
      value      

  static java.lang.String formatCompact4Digits(double);
    descriptor: (D)Ljava/lang/String;
    flags: (0x0008) ACC_STATIC
    Code:
      stack=7, locals=2, args_size=1
        start local 0 // double value
         0: .line 54
            getstatic java.util.Locale.ROOT:Ljava/util/Locale;
            ldc "%.4g"
            iconst_1
            anewarray java.lang.Object
            dup
            iconst_0
            dload 0 /* value */
            invokestatic java.lang.Double.valueOf:(D)Ljava/lang/Double;
            aastore
            invokestatic java.lang.String.format:(Ljava/util/Locale;Ljava/lang/String;[Ljava/lang/Object;)Ljava/lang/String;
            areturn
        end local 0 // double value
      LocalVariableTable:
        Start  End  Slot   Name  Signature
            0    1     0  value  D
    MethodParameters:
       Name  Flags
      value  

  static boolean stringIsNullOrEmpty(java.lang.String);
    descriptor: (Ljava/lang/String;)Z
    flags: (0x0008) ACC_STATIC
    Code:
      stack=1, locals=1, args_size=1
        start local 0 // java.lang.String string
         0: .line 58
            aload 0 /* string */
            ifnull 1
            aload 0 /* string */
            invokevirtual java.lang.String.isEmpty:()Z
            ifne 1
            iconst_0
            ireturn
      StackMap locals:
      StackMap stack:
         1: iconst_1
            ireturn
        end local 0 // java.lang.String string
      LocalVariableTable:
        Start  End  Slot    Name  Signature
            0    2     0  string  Ljava/lang/String;
    RuntimeVisibleTypeAnnotations: 
      METHOD_FORMAL_PARAMETER
        org.checkerframework.checker.nullness.qual.Nullable()
    MethodParameters:
        Name  Flags
      string  

  static java.lang.String nullToEmpty(java.lang.String);
    descriptor: (Ljava/lang/String;)Ljava/lang/String;
    flags: (0x0008) ACC_STATIC
    Code:
      stack=1, locals=1, args_size=1
        start local 0 // java.lang.String string
         0: .line 62
            aload 0 /* string */
            ifnonnull 1
            ldc ""
            goto 2
      StackMap locals:
      StackMap stack:
         1: aload 0 /* string */
      StackMap locals:
      StackMap stack: java.lang.String
         2: areturn
        end local 0 // java.lang.String string
      LocalVariableTable:
        Start  End  Slot    Name  Signature
            0    3     0  string  Ljava/lang/String;
    RuntimeVisibleTypeAnnotations: 
      METHOD_FORMAL_PARAMETER
        org.checkerframework.checker.nullness.qual.Nullable()
    MethodParameters:
        Name  Flags
      string  

  static java.lang.String emptyToNull(java.lang.String);
    descriptor: (Ljava/lang/String;)Ljava/lang/String;
    flags: (0x0008) ACC_STATIC
    Code:
      stack=1, locals=1, args_size=1
        start local 0 // java.lang.String string
         0: .line 66
            aload 0 /* string */
            invokestatic com.google.common.base.Platform.stringIsNullOrEmpty:(Ljava/lang/String;)Z
            ifeq 1
            aconst_null
            goto 2
      StackMap locals:
      StackMap stack:
         1: aload 0 /* string */
      StackMap locals:
      StackMap stack: java.lang.String
         2: areturn
        end local 0 // java.lang.String string
      LocalVariableTable:
        Start  End  Slot    Name  Signature
            0    3     0  string  Ljava/lang/String;
    RuntimeVisibleTypeAnnotations: 
      METHOD_FORMAL_PARAMETER
        org.checkerframework.checker.nullness.qual.Nullable()
    MethodParameters:
        Name  Flags
      string  

  static com.google.common.base.CommonPattern compilePattern(java.lang.String);
    descriptor: (Ljava/lang/String;)Lcom/google/common/base/CommonPattern;
    flags: (0x0008) ACC_STATIC
    Code:
      stack=2, locals=1, args_size=1
        start local 0 // java.lang.String pattern
         0: .line 70
            aload 0 /* pattern */
            invokestatic com.google.common.base.Preconditions.checkNotNull:(Ljava/lang/Object;)Ljava/lang/Object;
            pop
         1: .line 71
            getstatic com.google.common.base.Platform.patternCompiler:Lcom/google/common/base/PatternCompiler;
            aload 0 /* pattern */
            invokeinterface com.google.common.base.PatternCompiler.compile:(Ljava/lang/String;)Lcom/google/common/base/CommonPattern;
            areturn
        end local 0 // java.lang.String pattern
      LocalVariableTable:
        Start  End  Slot     Name  Signature
            0    2     0  pattern  Ljava/lang/String;
    MethodParameters:
         Name  Flags
      pattern  

  static boolean patternCompilerIsPcreLike();
    descriptor: ()Z
    flags: (0x0008) ACC_STATIC
    Code:
      stack=1, locals=0, args_size=0
         0: .line 75
            getstatic com.google.common.base.Platform.patternCompiler:Lcom/google/common/base/PatternCompiler;
            invokeinterface com.google.common.base.PatternCompiler.isPcreLike:()Z
            ireturn
      LocalVariableTable:
        Start  End  Slot  Name  Signature

  private static com.google.common.base.PatternCompiler loadPatternCompiler();
    descriptor: ()Lcom/google/common/base/PatternCompiler;
    flags: (0x000a) ACC_PRIVATE, ACC_STATIC
    Code:
      stack=2, locals=0, args_size=0
         0: .line 79
            new com.google.common.base.Platform$JdkPatternCompiler
            dup
            invokespecial com.google.common.base.Platform$JdkPatternCompiler.<init>:()V
            areturn
      LocalVariableTable:
        Start  End  Slot  Name  Signature

  private static void logPatternCompilerError(java.util.ServiceConfigurationError);
    descriptor: (Ljava/util/ServiceConfigurationError;)V
    flags: (0x000a) ACC_PRIVATE, ACC_STATIC
    Code:
      stack=4, locals=1, args_size=1
        start local 0 // java.util.ServiceConfigurationError e
         0: .line 83
            getstatic com.google.common.base.Platform.logger:Ljava/util/logging/Logger;
            getstatic java.util.logging.Level.WARNING:Ljava/util/logging/Level;
            ldc "Error loading regex compiler, falling back to next option"
            aload 0 /* e */
            invokevirtual java.util.logging.Logger.log:(Ljava/util/logging/Level;Ljava/lang/String;Ljava/lang/Throwable;)V
         1: .line 84
            return
        end local 0 // java.util.ServiceConfigurationError e
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    2     0     e  Ljava/util/ServiceConfigurationError;
    MethodParameters:
      Name  Flags
      e     

  static void checkGwtRpcEnabled();
    descriptor: ()V
    flags: (0x0008) ACC_STATIC
    Code:
      stack=7, locals=1, args_size=0
         0: .line 99
            ldc "guava.gwt.emergency_reenable_rpc"
            astore 0 /* propertyName */
        start local 0 // java.lang.String propertyName
         1: .line 101
            aload 0 /* propertyName */
            ldc "false"
            invokestatic java.lang.System.getProperty:(Ljava/lang/String;Ljava/lang/String;)Ljava/lang/String;
            invokestatic java.lang.Boolean.parseBoolean:(Ljava/lang/String;)Z
            ifne 9
         2: .line 102
            new java.lang.UnsupportedOperationException
            dup
         3: .line 104
            ldc "We are removing GWT-RPC support for Guava types. You can temporarily reenable support by setting the system property %s to true. For more about system properties, see %s. For more about Guava's GWT-RPC support, see %s."
            iconst_3
            anewarray java.lang.Object
            dup
            iconst_0
         4: .line 107
            aload 0 /* propertyName */
            aastore
            dup
            iconst_1
         5: .line 108
            ldc "https://stackoverflow.com/q/5189914/28465"
            aastore
            dup
            iconst_2
         6: .line 109
            ldc "https://groups.google.com/d/msg/guava-announce/zHZTFg7YF3o/rQNnwdHeEwAJ"
            aastore
         7: .line 103
            invokestatic com.google.common.base.Strings.lenientFormat:(Ljava/lang/String;[Ljava/lang/Object;)Ljava/lang/String;
         8: .line 102
            invokespecial java.lang.UnsupportedOperationException.<init>:(Ljava/lang/String;)V
            athrow
         9: .line 111
      StackMap locals: java.lang.String
      StackMap stack:
            getstatic com.google.common.base.Platform.logger:Ljava/util/logging/Logger;
        10: .line 112
            getstatic java.util.logging.Level.WARNING:Ljava/util/logging/Level;
        11: .line 113
            ldc "Later in 2020, we will remove GWT-RPC support for Guava types. You are seeing this warning because you are sending a Guava type over GWT-RPC, which will break. You can identify which type by looking at the class name in the attached stack trace."
        12: .line 116
            new java.lang.Throwable
            dup
            invokespecial java.lang.Throwable.<init>:()V
        13: .line 111
            invokevirtual java.util.logging.Logger.log:(Ljava/util/logging/Level;Ljava/lang/String;Ljava/lang/Throwable;)V
        14: .line 118
            return
        end local 0 // java.lang.String propertyName
      LocalVariableTable:
        Start  End  Slot          Name  Signature
            1   15     0  propertyName  Ljava/lang/String;
}
SourceFile: "Platform.java"
NestMembers:
  com.google.common.base.Platform$JdkPatternCompiler
InnerClasses:
  private final JdkPatternCompiler = com.google.common.base.Platform$JdkPatternCompiler of com.google.common.base.Platform
    RuntimeInvisibleAnnotations: 
      com.google.common.annotations.GwtCompatible(emulated = true)