java.io
Interfaces 
DataInput
DataOutput
Externalizable
FileFilter
FilenameFilter
ObjectInput
ObjectInputValidation
ObjectOutput
ObjectStreamConstants
Serializable
Classes 
Bits
BufferedInputStream
BufferedOutputStream
BufferedReader
BufferedWriter
ByteArrayInputStream
ByteArrayOutputStream
CharArrayReader
CharArrayWriter
DataInputStream
DataOutputStream
File
FileDescriptor
FileInputStream
FileOutputStream
FilePermission
FilePermissionCollection
FileReader
FileSystem
FileWriter
FilterInputStream
FilterOutputStream
FilterReader
FilterWriter
InputStream
InputStreamReader
LineNumberInputStream
LineNumberReader
ObjectInputStream
ObjectOutputStream
ObjectStreamClass
ObjectStreamField
OutputStream
OutputStreamWriter
PipedInputStream
PipedOutputStream
PipedReader
PipedWriter
PrintStream
PrintWriter
PushbackInputStream
PushbackReader
RandomAccessFile
Reader
SequenceInputStream
SerializablePermission
StreamTokenizer
StringBufferInputStream
StringReader
StringWriter
Win32FileSystem
WinNTFileSystem
Writer
Exceptions 
CharConversionException
EOFException
FileNotFoundException
InterruptedIOException
InvalidClassException
InvalidObjectException
IOException
NotActiveException
NotSerializableException
ObjectStreamException
OptionalDataException
StreamCorruptedException
SyncFailedException
UnsupportedEncodingException
UTFDataFormatException
WriteAbortedException