```
public interface BookieProtocol
```
The packets of the Bookie protocol all have a 4-byte integer indicating the type of request or response at the very beginning of the packet followed by a payload.

Nested Class Summary

Nested Classes
Modifier and Type	Interface	Description
`static class`	`BookieProtocol.AddResponse`	A response that adds data.
`static class`	`BookieProtocol.AuthRequest`	An authentication request.
`static class`	`BookieProtocol.AuthResponse`	A response with an authentication message.
`static class`	`BookieProtocol.BatchedReadRequest`	The request for reading data with batch optimization.
`static class`	`BookieProtocol.BatchedReadResponse`	The response for batched read.
`static class`	`BookieProtocol.ErrorResponse`	An error response.
`static class`	`BookieProtocol.PacketHeader`	The first int of a packet is the header.
`static class`	`BookieProtocol.ParsedAddRequest`	This is similar to add request, but it used when processing the request on the bookie side.
`static class`	`BookieProtocol.ReadRequest`	A Request that reads data.
`static class`	`BookieProtocol.ReadResponse`	A request that reads data.
`static class`	`BookieProtocol.Request`	A Bookie request object.
`static class`	`BookieProtocol.Response`	A response object.

Field Summary

Fields
Modifier and Type	Field	Description
`static byte`	`ADDENTRY`	The Add entry request payload will be a ledger entry exactly as it should be logged.
`static byte`	`AUTH`	Auth message.
`static byte`	`BATCH_READ_ENTRY`
`static byte`	`CURRENT_PROTOCOL_VERSION`	Current version of the protocol, which client will use.
`static int`	`EBADREQ`	The error code that indicates an invalid request type.
`static int`	`EBADVERSION`	The server version is incompatible with the client.
`static int`	`EFENCED`	Attempt to write to fenced ledger.
`static int`	`EIO`	General error occurred at the server.
`static int`	`ENOENTRY`	The error code that indicates that the requested entry does not exist.
`static int`	`ENOLEDGER`	The error code that indicates that the ledger does not exist.
`static int`	`EOK`	The error code that indicates success.
`static int`	`EREADONLY`	The server is running as read-only mode.
`static int`	`ETOOMANYREQUESTS`	Too many concurrent requests.
`static int`	`EUA`	Unauthorized access to ledger.
`static int`	`EUNKNOWNLEDGERSTATE`	Ledger in unknown state.
`static short`	`FLAG_DO_FENCING`
`static short`	`FLAG_HIGH_PRIORITY`
`static short`	`FLAG_NONE`
`static short`	`FLAG_RECOVERY_ADD`
`static byte`	`GET_BOOKIE_INFO`
`static long`	`INVALID_ENTRY_ID`	Entry Entry ID.
`static long`	`LAST_ADD_CONFIRMED`	Entry identifier representing a request to obtain the last add entry confirmed.
`static byte`	`LOWEST_COMPAT_PROTOCOL_VERSION`	Lowest protocol version which will work with the bookie.
`static int`	`MASTER_KEY_LENGTH`	The length of the master key in add packets.
`static byte`	`READ_LAC`
`static byte`	`READENTRY`	The Read entry request payload will be the ledger number and entry number to read.
`static byte`	`WRITE_LAC`

- Field Detail
  - LOWEST_COMPAT_PROTOCOL_VERSION
```
static final byte LOWEST_COMPAT_PROTOCOL_VERSION
```
    Lowest protocol version which will work with the bookie.
    
    See Also:
    
    Constant Field Values
  - CURRENT_PROTOCOL_VERSION
```
static final byte CURRENT_PROTOCOL_VERSION
```
    Current version of the protocol, which client will use.
    
    See Also:
    
    Constant Field Values
  - INVALID_ENTRY_ID
```
static final long INVALID_ENTRY_ID
```
    Entry Entry ID. To be used when no valid entry id can be assigned.
    
    See Also:
    
    Constant Field Values
  - LAST_ADD_CONFIRMED
```
static final long LAST_ADD_CONFIRMED
```
    Entry identifier representing a request to obtain the last add entry confirmed.
    
    See Also:
    
    Constant Field Values
  - MASTER_KEY_LENGTH
```
static final int MASTER_KEY_LENGTH
```
    The length of the master key in add packets. This is fixed at 20 for historic reasons. This is because it is always generated using the MacDigestManager regardless of whether Mac is being used for the digest or not
    
    See Also:
    
    Constant Field Values
  - ADDENTRY
```
static final byte ADDENTRY
```
    The Add entry request payload will be a ledger entry exactly as it should be logged. The response payload will be a 4-byte integer that has the error code followed by the 8-byte ledger number and 8-byte entry number of the entry written.
    
    See Also:
    
    Constant Field Values
  - READENTRY
```
static final byte READENTRY
```
    The Read entry request payload will be the ledger number and entry number to read. (The ledger number is an 8-byte integer and the entry number is a 8-byte integer.) The response payload will be a 4-byte integer representing an error code and a ledger entry if the error code is EOK, otherwise it will be the 8-byte ledger number and the 4-byte entry number requested. (Note that the first sixteen bytes of the entry happen to be the ledger number and entry number as well.)
    
    See Also:
    
    Constant Field Values
  - AUTH
```
static final byte AUTH
```
    Auth message. This code is for passing auth messages between the auth providers on the client and bookie. The message payload is determined by the auth providers themselves.
    
    See Also:
    
    Constant Field Values
  - READ_LAC
```
static final byte READ_LAC
```
    See Also:
    
    Constant Field Values
  - WRITE_LAC
```
static final byte WRITE_LAC
```
    See Also:
    
    Constant Field Values
  - GET_BOOKIE_INFO
```
static final byte GET_BOOKIE_INFO
```
    See Also:
    
    Constant Field Values
  - BATCH_READ_ENTRY
```
static final byte BATCH_READ_ENTRY
```
    See Also:
    
    Constant Field Values
  - EOK
```
static final int EOK
```
    The error code that indicates success.
    
    See Also:
    
    Constant Field Values
  - ENOLEDGER
```
static final int ENOLEDGER
```
    The error code that indicates that the ledger does not exist.
    
    See Also:
    
    Constant Field Values
  - ENOENTRY
```
static final int ENOENTRY
```
    The error code that indicates that the requested entry does not exist.
    
    See Also:
    
    Constant Field Values
  - EBADREQ
```
static final int EBADREQ
```
    The error code that indicates an invalid request type.
    
    See Also:
    
    Constant Field Values
  - EIO
```
static final int EIO
```
    General error occurred at the server.
    
    See Also:
    
    Constant Field Values
  - EUA
```
static final int EUA
```
    Unauthorized access to ledger.
    
    See Also:
    
    Constant Field Values
  - EBADVERSION
```
static final int EBADVERSION
```
    The server version is incompatible with the client.
    
    See Also:
    
    Constant Field Values
  - EFENCED
```
static final int EFENCED
```
    Attempt to write to fenced ledger.
    
    See Also:
    
    Constant Field Values
  - EREADONLY
```
static final int EREADONLY
```
    The server is running as read-only mode.
    
    See Also:
    
    Constant Field Values
  - ETOOMANYREQUESTS
```
static final int ETOOMANYREQUESTS
```
    Too many concurrent requests.
    
    See Also:
    
    Constant Field Values
  - EUNKNOWNLEDGERSTATE
```
static final int EUNKNOWNLEDGERSTATE
```
    Ledger in unknown state.
    
    See Also:
    
    Constant Field Values
  - FLAG_NONE
```
static final short FLAG_NONE
```
    See Also:
    
    Constant Field Values
  - FLAG_DO_FENCING
```
static final short FLAG_DO_FENCING
```
    See Also:
    
    Constant Field Values
  - FLAG_RECOVERY_ADD
```
static final short FLAG_RECOVERY_ADD
```
    See Also:
    
    Constant Field Values
  - FLAG_HIGH_PRIORITY
```
static final short FLAG_HIGH_PRIORITY
```
    See Also:
    
    Constant Field Values

Interface BookieProtocol

Nested Class Summary

Field Summary

Field Detail

LOWEST_COMPAT_PROTOCOL_VERSION

CURRENT_PROTOCOL_VERSION

INVALID_ENTRY_ID

LAST_ADD_CONFIRMED

MASTER_KEY_LENGTH

ADDENTRY

READENTRY

AUTH

READ_LAC

WRITE_LAC

GET_BOOKIE_INFO

BATCH_READ_ENTRY

EOK

ENOLEDGER

ENOENTRY

EBADREQ

EIO

EUA

EBADVERSION

EFENCED

EREADONLY

ETOOMANYREQUESTS

EUNKNOWNLEDGERSTATE

FLAG_NONE

FLAG_DO_FENCING

FLAG_RECOVERY_ADD

FLAG_HIGH_PRIORITY