com.allanbank.mongodb.client.message

Class AbstractMessage

java.lang.Object

com.allanbank.mongodb.client.message.AbstractMessage

All Implemented Interfaces:

Message

Direct Known Subclasses:

Command, Delete, GetMore, Insert, KillCursors, Query, Reply, Update

public abstract class AbstractMessage
extends Object
implements Message

Base class for a MongoDB message.

API Warning:

This class is NOT part of the drivers API. This class may be mutated in incompatible ways between any two releases of the driver.

Copyright ©:

2011-2013, Allanbank Consulting, Inc., All Rights Reserved

Field Summary

Fields

Modifier and Type	Field and Description
static int	HEADER_SIZE The size of a message header.
protected String	myCollectionName The name of the collection to operate on.
protected String	myDatabaseName The name of the database to operate on.

Constructor Summary

Constructors

Constructor and Description
AbstractMessage() Create a new AbstractMessage.
AbstractMessage(String databaseName, String collectionName, ReadPreference readPreference) Create a new AbstractMessage.
AbstractMessage(String databaseName, String collectionName, ReadPreference readPreference, VersionRange versionRange) Creates a new AbstractMessage.

Method Summary

Methods

Modifier and Type	Method and Description
boolean	equals(Object object) Determines if the passed object is of this same type as this object and if so that its fields are equal.
protected void	finishHeader(BufferingBsonOutputStream stream, long start) Writes the MsgHeader messageLengthField in the header stream.
String	getCollectionName() Returns the name of the collection.
String	getDatabaseName() Returns the name of the database.
ReadPreference	getReadPreference() Provides the details on which servers are eligible to receive the message.
VersionRange	getRequiredVersionRange() Returns the required version range for the message.
int	hashCode() Computes a reasonable hash code.
protected void	init(String name) Initializes the database and collection name from the full database name.
protected void	writeHeader(BsonOutputStream stream, int requestId, int responseTo, Operation op, int length) Writes the MsgHeader to the stream.
protected long	writeHeader(BufferingBsonOutputStream stream, int requestId, int responseTo, Operation op) Writes the MsgHeader to the stream.

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface com.allanbank.mongodb.client.Message

getOperationName, size, validateSize, write, write

Field Detail

HEADER_SIZE

public static final int HEADER_SIZE

The size of a message header.

See Also:

Constant Field Values

myCollectionName

protected String myCollectionName

The name of the collection to operate on.

myDatabaseName

protected String myDatabaseName

The name of the database to operate on.

Constructor Detail

AbstractMessage

public AbstractMessage()

Create a new AbstractMessage.

AbstractMessage

public AbstractMessage(String databaseName,
               String collectionName,
               ReadPreference readPreference)

Create a new AbstractMessage.

Parameters:

databaseName - The name of the database.

collectionName - The name of the collection.

readPreference - The preferences for which servers to send the message.

AbstractMessage

public AbstractMessage(String databaseName,
               String collectionName,
               ReadPreference readPreference,
               VersionRange versionRange)

Creates a new AbstractMessage.

Parameters:

databaseName - The name of the database.

collectionName - The name of the collection.

readPreference - The preferences for which servers to send the message.

versionRange - The required range of versions of the server to support processing the message.

Method Detail

equals

public boolean equals(Object object)

Determines if the passed object is of this same type as this object and if so that its fields are equal.

Overrides:

equals in class Object

Parameters:

object - The object to compare to.

See Also:

Object.equals(java.lang.Object)

getCollectionName

public String getCollectionName()

Returns the name of the collection.

Returns:

The name of the collection.

getDatabaseName

public String getDatabaseName()

Returns the name of the database.

Specified by:

getDatabaseName in interface Message

Returns:

The name of the database.

getReadPreference

public ReadPreference getReadPreference()

Provides the details on which servers are eligible to receive the message.

Returns the message's read preference.

Specified by:

getReadPreference in interface Message

Returns:

The ReadPreference for which servers should be sent the request.

getRequiredVersionRange

public VersionRange getRequiredVersionRange()

Returns the required version range for the message.

This may be null which should be interpreted to mean that all versions of the server support the message's operation. In reality that is probably more accurately stated as all supported versions.

Specified by:

getRequiredVersionRange in interface Message

Returns:

The version of the server that introduced support for the operation.

hashCode

public int hashCode()

Computes a reasonable hash code.

Overrides:

hashCode in class Object

Returns:

The hash code value.

finishHeader

protected void finishHeader(BufferingBsonOutputStream stream,
                long start)

Writes the MsgHeader messageLengthField in the header stream.

 
 struct MsgHeader {
     int32   messageLength; // total message size, including this
     int32   requestID;     // identifier for this message
     int32   responseTo;    // requestID from the original request
                            //   (used in reponses from db)
     int32   opCode;        // request type - see table below
 }
 
 

Parameters:

stream - The stream to write to.

start - The position of the start of the header for the message.

init

protected void init(String name)

Initializes the database and collection name from the full database name.

Parameters:

name - The full database name.

writeHeader

protected void writeHeader(BsonOutputStream stream,
               int requestId,
               int responseTo,
               Operation op,
               int length)

Writes the MsgHeader to the stream.

 
 struct MsgHeader {
     int32   messageLength; // total message size, including this
     int32   requestID;     // identifier for this message
     int32   responseTo;    // requestID from the original request
                            //   (used in reponses from db)
     int32   opCode;        // request type - see table below
 }
 
 

Parameters:

stream - The stream to write to.

requestId - The requestID from above.

responseTo - The responseTo from above.

op - The operation for the opCode field.

length - The length of the message including the header.

writeHeader

protected long writeHeader(BufferingBsonOutputStream stream,
               int requestId,
               int responseTo,
               Operation op)

Writes the MsgHeader to the stream.

 
 struct MsgHeader {
     int32   messageLength; // total message size, including this
     int32   requestID;     // identifier for this message
     int32   responseTo;    // requestID from the original request
                            //   (used in reponses from db)
     int32   opCode;        // request type - see table below
 }
 
 

Parameters:

stream - The stream to write to.

requestId - The requestID from above.

responseTo - The responseTo from above.

op - The operation for the opCode field.

Returns:

The position of the start of the header for the message.