http://netty.io/netty-all/: Netty is an asynchronous event-driven network application framework for rapid development of maintainable high performance protocol servers and clients. (The Netty Project) 
public class io.netty.channel.DefaultFileRegion extends io.netty.util.AbstractReferenceCounted implements io.netty.channel.FileRegion
  minor version: 0
  major version: 59
  flags: flags: (0x0021) ACC_PUBLIC, ACC_SUPER
  this_class: io.netty.channel.DefaultFileRegion
  super_class: io.netty.util.AbstractReferenceCounted
{
  private static final io.netty.util.internal.logging.InternalLogger logger;
    descriptor: Lio/netty/util/internal/logging/InternalLogger;
    flags: (0x001a) ACC_PRIVATE, ACC_STATIC, ACC_FINAL

  private final java.io.File f;
    descriptor: Ljava/io/File;
    flags: (0x0012) ACC_PRIVATE, ACC_FINAL

  private final long position;
    descriptor: J
    flags: (0x0012) ACC_PRIVATE, ACC_FINAL

  private final long count;
    descriptor: J
    flags: (0x0012) ACC_PRIVATE, ACC_FINAL

  private long transferred;
    descriptor: J
    flags: (0x0002) ACC_PRIVATE

  private java.nio.channels.FileChannel file;
    descriptor: Ljava/nio/channels/FileChannel;
    flags: (0x0002) ACC_PRIVATE

  static void <clinit>();
    descriptor: ()V
    flags: (0x0008) ACC_STATIC
    Code:
      stack=1, locals=0, args_size=0
         0: .line 37
            ldc Lio/netty/channel/DefaultFileRegion;
            invokestatic io.netty.util.internal.logging.InternalLoggerFactory.getInstance:(Ljava/lang/Class;)Lio/netty/util/internal/logging/InternalLogger;
            putstatic io.netty.channel.DefaultFileRegion.logger:Lio/netty/util/internal/logging/InternalLogger;
            return
      LocalVariableTable:
        Start  End  Slot  Name  Signature

  public void <init>(java.nio.channels.FileChannel, long, long);
    descriptor: (Ljava/nio/channels/FileChannel;JJ)V
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=5, locals=6, args_size=4
        start local 0 // io.netty.channel.DefaultFileRegion this
        start local 1 // java.nio.channels.FileChannel file
        start local 2 // long position
        start local 4 // long count
         0: .line 51
            aload 0 /* this */
            invokespecial io.netty.util.AbstractReferenceCounted.<init>:()V
         1: .line 52
            aload 1 /* file */
            ifnonnull 3
         2: .line 53
            new java.lang.NullPointerException
            dup
            ldc "file"
            invokespecial java.lang.NullPointerException.<init>:(Ljava/lang/String;)V
            athrow
         3: .line 55
      StackMap locals: io.netty.channel.DefaultFileRegion java.nio.channels.FileChannel long long
      StackMap stack:
            lload 2 /* position */
            lconst_0
            lcmp
            ifge 5
         4: .line 56
            new java.lang.IllegalArgumentException
            dup
            new java.lang.StringBuilder
            dup
            ldc "position must be >= 0 but was "
            invokespecial java.lang.StringBuilder.<init>:(Ljava/lang/String;)V
            lload 2 /* position */
            invokevirtual java.lang.StringBuilder.append:(J)Ljava/lang/StringBuilder;
            invokevirtual java.lang.StringBuilder.toString:()Ljava/lang/String;
            invokespecial java.lang.IllegalArgumentException.<init>:(Ljava/lang/String;)V
            athrow
         5: .line 58
      StackMap locals:
      StackMap stack:
            lload 4 /* count */
            lconst_0
            lcmp
            ifge 7
         6: .line 59
            new java.lang.IllegalArgumentException
            dup
            new java.lang.StringBuilder
            dup
            ldc "count must be >= 0 but was "
            invokespecial java.lang.StringBuilder.<init>:(Ljava/lang/String;)V
            lload 4 /* count */
            invokevirtual java.lang.StringBuilder.append:(J)Ljava/lang/StringBuilder;
            invokevirtual java.lang.StringBuilder.toString:()Ljava/lang/String;
            invokespecial java.lang.IllegalArgumentException.<init>:(Ljava/lang/String;)V
            athrow
         7: .line 61
      StackMap locals:
      StackMap stack:
            aload 0 /* this */
            aload 1 /* file */
            putfield io.netty.channel.DefaultFileRegion.file:Ljava/nio/channels/FileChannel;
         8: .line 62
            aload 0 /* this */
            lload 2 /* position */
            putfield io.netty.channel.DefaultFileRegion.position:J
         9: .line 63
            aload 0 /* this */
            lload 4 /* count */
            putfield io.netty.channel.DefaultFileRegion.count:J
        10: .line 64
            aload 0 /* this */
            aconst_null
            putfield io.netty.channel.DefaultFileRegion.f:Ljava/io/File;
        11: .line 65
            return
        end local 4 // long count
        end local 2 // long position
        end local 1 // java.nio.channels.FileChannel file
        end local 0 // io.netty.channel.DefaultFileRegion this
      LocalVariableTable:
        Start  End  Slot      Name  Signature
            0   12     0      this  Lio/netty/channel/DefaultFileRegion;
            0   12     1      file  Ljava/nio/channels/FileChannel;
            0   12     2  position  J
            0   12     4     count  J
    MethodParameters:
          Name  Flags
      file      
      position  
      count     

  public void <init>(java.io.File, long, long);
    descriptor: (Ljava/io/File;JJ)V
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=5, locals=6, args_size=4
        start local 0 // io.netty.channel.DefaultFileRegion this
        start local 1 // java.io.File f
        start local 2 // long position
        start local 4 // long count
         0: .line 75
            aload 0 /* this */
            invokespecial io.netty.util.AbstractReferenceCounted.<init>:()V
         1: .line 76
            aload 1 /* f */
            ifnonnull 3
         2: .line 77
            new java.lang.NullPointerException
            dup
            ldc "f"
            invokespecial java.lang.NullPointerException.<init>:(Ljava/lang/String;)V
            athrow
         3: .line 79
      StackMap locals: io.netty.channel.DefaultFileRegion java.io.File long long
      StackMap stack:
            lload 2 /* position */
            lconst_0
            lcmp
            ifge 5
         4: .line 80
            new java.lang.IllegalArgumentException
            dup
            new java.lang.StringBuilder
            dup
            ldc "position must be >= 0 but was "
            invokespecial java.lang.StringBuilder.<init>:(Ljava/lang/String;)V
            lload 2 /* position */
            invokevirtual java.lang.StringBuilder.append:(J)Ljava/lang/StringBuilder;
            invokevirtual java.lang.StringBuilder.toString:()Ljava/lang/String;
            invokespecial java.lang.IllegalArgumentException.<init>:(Ljava/lang/String;)V
            athrow
         5: .line 82
      StackMap locals:
      StackMap stack:
            lload 4 /* count */
            lconst_0
            lcmp
            ifge 7
         6: .line 83
            new java.lang.IllegalArgumentException
            dup
            new java.lang.StringBuilder
            dup
            ldc "count must be >= 0 but was "
            invokespecial java.lang.StringBuilder.<init>:(Ljava/lang/String;)V
            lload 4 /* count */
            invokevirtual java.lang.StringBuilder.append:(J)Ljava/lang/StringBuilder;
            invokevirtual java.lang.StringBuilder.toString:()Ljava/lang/String;
            invokespecial java.lang.IllegalArgumentException.<init>:(Ljava/lang/String;)V
            athrow
         7: .line 85
      StackMap locals:
      StackMap stack:
            aload 0 /* this */
            lload 2 /* position */
            putfield io.netty.channel.DefaultFileRegion.position:J
         8: .line 86
            aload 0 /* this */
            lload 4 /* count */
            putfield io.netty.channel.DefaultFileRegion.count:J
         9: .line 87
            aload 0 /* this */
            aload 1 /* f */
            putfield io.netty.channel.DefaultFileRegion.f:Ljava/io/File;
        10: .line 88
            return
        end local 4 // long count
        end local 2 // long position
        end local 1 // java.io.File f
        end local 0 // io.netty.channel.DefaultFileRegion this
      LocalVariableTable:
        Start  End  Slot      Name  Signature
            0   11     0      this  Lio/netty/channel/DefaultFileRegion;
            0   11     1         f  Ljava/io/File;
            0   11     2  position  J
            0   11     4     count  J
    MethodParameters:
          Name  Flags
      f         
      position  
      count     

  public boolean isOpen();
    descriptor: ()Z
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=1, locals=1, args_size=1
        start local 0 // io.netty.channel.DefaultFileRegion this
         0: .line 94
            aload 0 /* this */
            getfield io.netty.channel.DefaultFileRegion.file:Ljava/nio/channels/FileChannel;
            ifnull 1
            iconst_1
            ireturn
      StackMap locals:
      StackMap stack:
         1: iconst_0
            ireturn
        end local 0 // io.netty.channel.DefaultFileRegion this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    2     0  this  Lio/netty/channel/DefaultFileRegion;

  public void open();
    descriptor: ()V
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=5, locals=1, args_size=1
        start local 0 // io.netty.channel.DefaultFileRegion this
         0: .line 101
            aload 0 /* this */
            invokevirtual io.netty.channel.DefaultFileRegion.isOpen:()Z
            ifne 2
            aload 0 /* this */
            invokevirtual io.netty.channel.DefaultFileRegion.refCnt:()I
            ifle 2
         1: .line 103
            aload 0 /* this */
            new java.io.RandomAccessFile
            dup
            aload 0 /* this */
            getfield io.netty.channel.DefaultFileRegion.f:Ljava/io/File;
            ldc "r"
            invokespecial java.io.RandomAccessFile.<init>:(Ljava/io/File;Ljava/lang/String;)V
            invokevirtual java.io.RandomAccessFile.getChannel:()Ljava/nio/channels/FileChannel;
            putfield io.netty.channel.DefaultFileRegion.file:Ljava/nio/channels/FileChannel;
         2: .line 105
      StackMap locals:
      StackMap stack:
            return
        end local 0 // io.netty.channel.DefaultFileRegion this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    3     0  this  Lio/netty/channel/DefaultFileRegion;
    Exceptions:
      throws java.io.IOException

  public long position();
    descriptor: ()J
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=2, locals=1, args_size=1
        start local 0 // io.netty.channel.DefaultFileRegion this
         0: .line 109
            aload 0 /* this */
            getfield io.netty.channel.DefaultFileRegion.position:J
            lreturn
        end local 0 // io.netty.channel.DefaultFileRegion this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    1     0  this  Lio/netty/channel/DefaultFileRegion;

  public long count();
    descriptor: ()J
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=2, locals=1, args_size=1
        start local 0 // io.netty.channel.DefaultFileRegion this
         0: .line 114
            aload 0 /* this */
            getfield io.netty.channel.DefaultFileRegion.count:J
            lreturn
        end local 0 // io.netty.channel.DefaultFileRegion this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    1     0  this  Lio/netty/channel/DefaultFileRegion;

  public long transfered();
    descriptor: ()J
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=2, locals=1, args_size=1
        start local 0 // io.netty.channel.DefaultFileRegion this
         0: .line 120
            aload 0 /* this */
            getfield io.netty.channel.DefaultFileRegion.transferred:J
            lreturn
        end local 0 // io.netty.channel.DefaultFileRegion this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    1     0  this  Lio/netty/channel/DefaultFileRegion;
    RuntimeVisibleAnnotations: 
      java.lang.Deprecated()

  public long transferred();
    descriptor: ()J
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=2, locals=1, args_size=1
        start local 0 // io.netty.channel.DefaultFileRegion this
         0: .line 125
            aload 0 /* this */
            getfield io.netty.channel.DefaultFileRegion.transferred:J
            lreturn
        end local 0 // io.netty.channel.DefaultFileRegion this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    1     0  this  Lio/netty/channel/DefaultFileRegion;

  public long transferTo(java.nio.channels.WritableByteChannel, long);
    descriptor: (Ljava/nio/channels/WritableByteChannel;J)J
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=7, locals=8, args_size=3
        start local 0 // io.netty.channel.DefaultFileRegion this
        start local 1 // java.nio.channels.WritableByteChannel target
        start local 2 // long position
         0: .line 130
            aload 0 /* this */
            getfield io.netty.channel.DefaultFileRegion.count:J
            lload 2 /* position */
            lsub
            lstore 4 /* count */
        start local 4 // long count
         1: .line 131
            lload 4 /* count */
            lconst_0
            lcmp
            iflt 2
            lload 2 /* position */
            lconst_0
            lcmp
            ifge 7
         2: .line 132
      StackMap locals: long
      StackMap stack:
            new java.lang.IllegalArgumentException
            dup
         3: .line 133
            new java.lang.StringBuilder
            dup
            ldc "position out of range: "
            invokespecial java.lang.StringBuilder.<init>:(Ljava/lang/String;)V
            lload 2 /* position */
            invokevirtual java.lang.StringBuilder.append:(J)Ljava/lang/StringBuilder;
         4: .line 134
            ldc " (expected: 0 - "
            invokevirtual java.lang.StringBuilder.append:(Ljava/lang/String;)Ljava/lang/StringBuilder;
            aload 0 /* this */
            getfield io.netty.channel.DefaultFileRegion.count:J
            lconst_1
            lsub
            invokevirtual java.lang.StringBuilder.append:(J)Ljava/lang/StringBuilder;
            bipush 41
            invokevirtual java.lang.StringBuilder.append:(C)Ljava/lang/StringBuilder;
         5: .line 133
            invokevirtual java.lang.StringBuilder.toString:()Ljava/lang/String;
         6: .line 132
            invokespecial java.lang.IllegalArgumentException.<init>:(Ljava/lang/String;)V
            athrow
         7: .line 136
      StackMap locals:
      StackMap stack:
            lload 4 /* count */
            lconst_0
            lcmp
            ifne 9
         8: .line 137
            lconst_0
            lreturn
         9: .line 139
      StackMap locals:
      StackMap stack:
            aload 0 /* this */
            invokevirtual io.netty.channel.DefaultFileRegion.refCnt:()I
            ifne 11
        10: .line 140
            new io.netty.util.IllegalReferenceCountException
            dup
            iconst_0
            invokespecial io.netty.util.IllegalReferenceCountException.<init>:(I)V
            athrow
        11: .line 143
      StackMap locals:
      StackMap stack:
            aload 0 /* this */
            invokevirtual io.netty.channel.DefaultFileRegion.open:()V
        12: .line 145
            aload 0 /* this */
            getfield io.netty.channel.DefaultFileRegion.file:Ljava/nio/channels/FileChannel;
            aload 0 /* this */
            getfield io.netty.channel.DefaultFileRegion.position:J
            lload 2 /* position */
            ladd
            lload 4 /* count */
            aload 1 /* target */
            invokevirtual java.nio.channels.FileChannel.transferTo:(JJLjava/nio/channels/WritableByteChannel;)J
            lstore 6 /* written */
        start local 6 // long written
        13: .line 146
            lload 6 /* written */
            lconst_0
            lcmp
            ifle 15
        14: .line 147
            aload 0 /* this */
            dup
            getfield io.netty.channel.DefaultFileRegion.transferred:J
            lload 6 /* written */
            ladd
            putfield io.netty.channel.DefaultFileRegion.transferred:J
        15: .line 149
      StackMap locals: long
      StackMap stack:
            lload 6 /* written */
            lreturn
        end local 6 // long written
        end local 4 // long count
        end local 2 // long position
        end local 1 // java.nio.channels.WritableByteChannel target
        end local 0 // io.netty.channel.DefaultFileRegion this
      LocalVariableTable:
        Start  End  Slot      Name  Signature
            0   16     0      this  Lio/netty/channel/DefaultFileRegion;
            0   16     1    target  Ljava/nio/channels/WritableByteChannel;
            0   16     2  position  J
            1   16     4     count  J
           13   16     6   written  J
    Exceptions:
      throws java.io.IOException
    MethodParameters:
          Name  Flags
      target    
      position  

  protected void deallocate();
    descriptor: ()V
    flags: (0x0004) ACC_PROTECTED
    Code:
      stack=3, locals=3, args_size=1
        start local 0 // io.netty.channel.DefaultFileRegion this
         0: .line 154
            aload 0 /* this */
            getfield io.netty.channel.DefaultFileRegion.file:Ljava/nio/channels/FileChannel;
            astore 1 /* file */
        start local 1 // java.nio.channels.FileChannel file
         1: .line 156
            aload 1 /* file */
            ifnonnull 3
         2: .line 157
            return
         3: .line 159
      StackMap locals: java.nio.channels.FileChannel
      StackMap stack:
            aload 0 /* this */
            aconst_null
            putfield io.netty.channel.DefaultFileRegion.file:Ljava/nio/channels/FileChannel;
         4: .line 162
            aload 1 /* file */
            invokevirtual java.nio.channels.FileChannel.close:()V
         5: .line 163
            goto 9
      StackMap locals:
      StackMap stack: java.io.IOException
         6: astore 2 /* e */
        start local 2 // java.io.IOException e
         7: .line 164
            getstatic io.netty.channel.DefaultFileRegion.logger:Lio/netty/util/internal/logging/InternalLogger;
            invokeinterface io.netty.util.internal.logging.InternalLogger.isWarnEnabled:()Z
            ifeq 9
         8: .line 165
            getstatic io.netty.channel.DefaultFileRegion.logger:Lio/netty/util/internal/logging/InternalLogger;
            ldc "Failed to close a file."
            aload 2 /* e */
            invokeinterface io.netty.util.internal.logging.InternalLogger.warn:(Ljava/lang/String;Ljava/lang/Throwable;)V
        end local 2 // java.io.IOException e
         9: .line 168
      StackMap locals:
      StackMap stack:
            return
        end local 1 // java.nio.channels.FileChannel file
        end local 0 // io.netty.channel.DefaultFileRegion this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0   10     0  this  Lio/netty/channel/DefaultFileRegion;
            1   10     1  file  Ljava/nio/channels/FileChannel;
            7    9     2     e  Ljava/io/IOException;
      Exception table:
        from    to  target  type
           4     5       6  Class java.io.IOException

  public io.netty.channel.FileRegion retain();
    descriptor: ()Lio/netty/channel/FileRegion;
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=1, locals=1, args_size=1
        start local 0 // io.netty.channel.DefaultFileRegion this
         0: .line 172
            aload 0 /* this */
            invokespecial io.netty.util.AbstractReferenceCounted.retain:()Lio/netty/util/ReferenceCounted;
            pop
         1: .line 173
            aload 0 /* this */
            areturn
        end local 0 // io.netty.channel.DefaultFileRegion this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    2     0  this  Lio/netty/channel/DefaultFileRegion;

  public io.netty.channel.FileRegion retain(int);
    descriptor: (I)Lio/netty/channel/FileRegion;
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=2, locals=2, args_size=2
        start local 0 // io.netty.channel.DefaultFileRegion this
        start local 1 // int increment
         0: .line 178
            aload 0 /* this */
            iload 1 /* increment */
            invokespecial io.netty.util.AbstractReferenceCounted.retain:(I)Lio/netty/util/ReferenceCounted;
            pop
         1: .line 179
            aload 0 /* this */
            areturn
        end local 1 // int increment
        end local 0 // io.netty.channel.DefaultFileRegion this
      LocalVariableTable:
        Start  End  Slot       Name  Signature
            0    2     0       this  Lio/netty/channel/DefaultFileRegion;
            0    2     1  increment  I
    MethodParameters:
           Name  Flags
      increment  

  public io.netty.channel.FileRegion touch();
    descriptor: ()Lio/netty/channel/FileRegion;
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=1, locals=1, args_size=1
        start local 0 // io.netty.channel.DefaultFileRegion this
         0: .line 184
            aload 0 /* this */
            areturn
        end local 0 // io.netty.channel.DefaultFileRegion this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    1     0  this  Lio/netty/channel/DefaultFileRegion;

  public io.netty.channel.FileRegion touch(java.lang.Object);
    descriptor: (Ljava/lang/Object;)Lio/netty/channel/FileRegion;
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=1, locals=2, args_size=2
        start local 0 // io.netty.channel.DefaultFileRegion this
        start local 1 // java.lang.Object hint
         0: .line 189
            aload 0 /* this */
            areturn
        end local 1 // java.lang.Object hint
        end local 0 // io.netty.channel.DefaultFileRegion this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    1     0  this  Lio/netty/channel/DefaultFileRegion;
            0    1     1  hint  Ljava/lang/Object;
    MethodParameters:
      Name  Flags
      hint  

  public io.netty.util.ReferenceCounted retain(int);
    descriptor: (I)Lio/netty/util/ReferenceCounted;
    flags: (0x1041) ACC_PUBLIC, ACC_BRIDGE, ACC_SYNTHETIC
    Code:
      stack=2, locals=2, args_size=2
         0: .line 1
            aload 0
            iload 1
            invokevirtual io.netty.channel.DefaultFileRegion.retain:(I)Lio/netty/channel/FileRegion;
            areturn
      LocalVariableTable:
        Start  End  Slot  Name  Signature

  public io.netty.util.ReferenceCounted retain();
    descriptor: ()Lio/netty/util/ReferenceCounted;
    flags: (0x1041) ACC_PUBLIC, ACC_BRIDGE, ACC_SYNTHETIC
    Code:
      stack=1, locals=1, args_size=1
         0: .line 1
            aload 0
            invokevirtual io.netty.channel.DefaultFileRegion.retain:()Lio/netty/channel/FileRegion;
            areturn
      LocalVariableTable:
        Start  End  Slot  Name  Signature

  public io.netty.util.ReferenceCounted touch(java.lang.Object);
    descriptor: (Ljava/lang/Object;)Lio/netty/util/ReferenceCounted;
    flags: (0x1041) ACC_PUBLIC, ACC_BRIDGE, ACC_SYNTHETIC
    Code:
      stack=2, locals=2, args_size=2
         0: .line 1
            aload 0
            aload 1
            invokevirtual io.netty.channel.DefaultFileRegion.touch:(Ljava/lang/Object;)Lio/netty/channel/FileRegion;
            areturn
      LocalVariableTable:
        Start  End  Slot  Name  Signature

  public io.netty.util.ReferenceCounted touch();
    descriptor: ()Lio/netty/util/ReferenceCounted;
    flags: (0x1041) ACC_PUBLIC, ACC_BRIDGE, ACC_SYNTHETIC
    Code:
      stack=1, locals=1, args_size=1
         0: .line 1
            aload 0
            invokevirtual io.netty.channel.DefaultFileRegion.touch:()Lio/netty/channel/FileRegion;
            areturn
      LocalVariableTable:
        Start  End  Slot  Name  Signature
}
SourceFile: "DefaultFileRegion.java"