Package com.blackrook.redis.io

Class RESPReader

java.lang.Object

com.blackrook.redis.io.RESPReader

public class RESPReader
extends Object

Reader class for reading responses from a Redis Socket connection.

Author:

Matthew Tropiano

Constructor Summary

Constructors

Constructor	Description
RESPReader(InputStream in)	Creates a RedisReader attached to an input stream.

Method Summary

Modifier and Type	Method	Description
String[]	readArray()	Reads and expects an Array Reply from Redis.
protected int	readBulk(DataList dl, int len)	Reads bytes until CRLF and returns how many bytes in the "string" (before CRLF).
Long	readInteger()	Reads and expects an Integer Reply from Redis.
protected int	readLine(DataList dl)	Reads bytes until CRLF and returns how many bytes in the "string" (before CRLF).
RedisObject	readObject()	Reads a full Redis data structure as a RedisObject.
boolean	readOK()	Reads and expects "OK" from Redis.
boolean	readPong()	Reads and expects "PONG" from Redis.
boolean	readQueued()	Reads and expects "QUEUED" from Redis.
String	readRaw()	Reads until a full Redis data structure is read.
String	readString()	Reads and expects a String Reply from Redis, bulk or otherwise.

Methods inherited from class java.lang.Object

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

Constructor Detail

RESPReader

public RESPReader(InputStream in)

Creates a RedisReader attached to an input stream.

Parameters:

in - the InputStream to wrap.

Method Detail

readOK

public boolean readOK()

Reads and expects "OK" from Redis. Will block until something is read from the stream. Should be used if AND ONLY IF "OK" is expected.

Returns:

true.

Throws:

RedisException - if the server reports an error, or isn't OK.

RedisParseException - if an error occurs during the read.

readQueued

public boolean readQueued()

Reads and expects "QUEUED" from Redis. Will block until something is read from the stream. Should be used if AND ONLY IF "QUEUED" is expected.

Returns:

true.

Throws:

RedisException - if the server reports an error, or isn't QUEUED.

RedisParseException - if an error occurs during the read.

readPong

public boolean readPong()

Reads and expects "PONG" from Redis. Will block until something is read from the stream. Should be used if AND ONLY IF "PONG" is expected.

Returns:

true.

Throws:

RedisException - if the server reports an error, or isn't PONG.

RedisParseException - if an error occurs during the read.

readInteger

public Long readInteger()

Reads and expects an Integer Reply from Redis. Will block until something is read from the stream. Should be used if AND ONLY IF an Integer or Null is expected.

Returns:

a long or null reply.

Throws:

RedisException - if the server reports an error.

RedisParseException - if an error occurs during the read.

readString

public String readString()

Reads and expects a String Reply from Redis, bulk or otherwise. Will block until something is read from the stream. Should be used if AND ONLY IF a non-array or Null is expected. Integers are cast to Strings.

Returns:

a long or null reply.

Throws:

RedisException - if the server reports an error.

RedisParseException - if an error occurs during the read.

readArray

public String[] readArray()

Reads and expects an Array Reply from Redis. Will block until something is read from the stream. Should be used if AND ONLY IF an array or Null is expected. Integers are cast to Strings.

Returns:

an array or null reply. Arrays may contain null elements!

Throws:

RedisException - if the server reports an error.

RedisParseException - if an error occurs during the read.

readObject

public RedisObject readObject()

Reads a full Redis data structure as a RedisObject. This is useful for commands that return complex or not-yet-supported responses. Will block until something is read completely from the stream.

Returns:

a full string with all breaks and newlines.

Throws:

RedisException - if the server reports an error.

RedisParseException - if an error occurs during the read.

readRaw

public String readRaw()

Reads until a full Redis data structure is read. Will block until something is read completely from the stream.

Returns:

a full string with all breaks and newlines.

Throws:

RedisException - if the server reports an error.

RedisParseException - if an error occurs during the read.

readLine

protected int readLine(DataList dl)
                throws IOException

Reads bytes until CRLF and returns how many bytes in the "string" (before CRLF).

Parameters:

dl - the data buffer to read from.

Returns:

the amount of bytes read.

Throws:

IOException

readBulk

protected int readBulk(DataList dl,
                       int len)
                throws IOException

Reads bytes until CRLF and returns how many bytes in the "string" (before CRLF).

Parameters:

dl - the data buffer to read from.

len - the maximum amount of bytes to read.

Returns:

the amount of bytes read.

Throws:

IOException