org.apache.avro

Class Protocol

java.lang.Object

org.apache.avro.Protocol

public class Protocol
extends Object

A set of messages forming an application protocol.

A protocol consists of:

• a name for the protocol;
• an optional namespace, further qualifying the name;
• a list of types, or named schemas;
• a list of errors, or named schemas for exceptions;
• a list of named messages, each of which specifies,
  • request, the parameter schemas;
  • one of either;
    • one-way
    or
    • response, the response schema;
    • errors, an optional list of potential error schema names.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
class	Protocol.Message A protocol message.

Field Summary

Fields

Modifier and Type	Field and Description
static Schema	SYSTEM_ERROR An error that can be thrown by any message.
static Schema	SYSTEM_ERRORS Union type for generating system errors.
static long	VERSION The version of the protocol specification implemented here.

Constructor Summary

Constructors

Constructor and Description
Protocol(String name, String namespace)
Protocol(String name, String doc, String namespace)

Method Summary

Methods

Modifier and Type	Method and Description
void	addProp(String name, String value) Adds a property with the given name name and value value.
Protocol.Message	createMessage(String name, String doc, Map<String,String> propMap, Schema request) Create a one-way message.
Protocol.Message	createMessage(String name, String doc, Map<String,String> propMap, Schema request, Schema response, Schema errors) Create a two-way message.
Protocol.Message	createMessage(String name, String doc, Schema request) Deprecated.
Protocol.Message	createMessage(String name, String doc, Schema request, Schema response, Schema errors) Deprecated.
boolean	equals(Object o)
String	getDoc() Doc string for this protocol.
byte[]	getMD5() Return the MD5 hash of the text of this protocol.
Map<String,Protocol.Message>	getMessages() The messages of this protocol.
String	getName() The name of this protocol.
String	getNamespace() The namespace of this protocol.
String	getProp(String name) Returns the value of the named property in this schema.
Map<String,String>	getProps() Return the defined properties as an unmodifieable Map.
Schema	getType(String name) Returns the named type.
Collection<Schema>	getTypes() The types of this protocol.
int	hashCode()
static void	main(String[] args)
static Protocol	parse(File file) Read a protocol from a Json file.
static Protocol	parse(InputStream stream) Read a protocol from a Json stream.
static Protocol	parse(String string) Read a protocol from a Json string.
void	setTypes(Collection<Schema> newTypes) Set the types of this protocol.
String	toString() Render this as JSON.
String	toString(boolean pretty) Render this as JSON.

Methods inherited from class java.lang.Object

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

Field Detail

VERSION

public static final long VERSION

The version of the protocol specification implemented here.

See Also:

Constant Field Values

SYSTEM_ERROR

public static final Schema SYSTEM_ERROR

An error that can be thrown by any message.

SYSTEM_ERRORS

public static final Schema SYSTEM_ERRORS

Union type for generating system errors.

Constructor Detail

Protocol

public Protocol(String name,
        String doc,
        String namespace)

Protocol

public Protocol(String name,
        String namespace)

Method Detail

getName

public String getName()

The name of this protocol.

getNamespace

public String getNamespace()

The namespace of this protocol. Qualifies its name.

getDoc

public String getDoc()

Doc string for this protocol.

getTypes

public Collection<Schema> getTypes()

The types of this protocol.

getType

public Schema getType(String name)

Returns the named type.

setTypes

public void setTypes(Collection<Schema> newTypes)

Set the types of this protocol.

getMessages

public Map<String,Protocol.Message> getMessages()

The messages of this protocol.

createMessage

@Deprecated
public Protocol.Message createMessage(String name,
                                        String doc,
                                        Schema request)

Deprecated.

Create a one-way message.

createMessage

public Protocol.Message createMessage(String name,
                             String doc,
                             Map<String,String> propMap,
                             Schema request)

Create a one-way message.

createMessage

@Deprecated
public Protocol.Message createMessage(String name,
                                        String doc,
                                        Schema request,
                                        Schema response,
                                        Schema errors)

Deprecated.

Create a two-way message.

createMessage

public Protocol.Message createMessage(String name,
                             String doc,
                             Map<String,String> propMap,
                             Schema request,
                             Schema response,
                             Schema errors)

Create a two-way message.

getProp

public String getProp(String name)

Returns the value of the named property in this schema. Returns null if there is no property with that name.

Parameters:

name -

addProp

public void addProp(String name,
           String value)

Adds a property with the given name name and value value. Neither name nor value can be null. It is illegal to add a property if another with the same name but different value already exists in this schema.

Parameters:

name - The name of the property to add

value - The value for the property to add

getProps

public Map<String,String> getProps()

Return the defined properties as an unmodifieable Map.

equals

public boolean equals(Object o)

Overrides:

equals in class Object

hashCode

public int hashCode()

Overrides:

hashCode in class Object

toString

public String toString()

Render this as JSON.

Overrides:

toString in class Object

toString

public String toString(boolean pretty)

Render this as JSON.

Parameters:

pretty - if true, pretty-print JSON.

getMD5

public byte[] getMD5()

Return the MD5 hash of the text of this protocol.

parse

public static Protocol parse(File file)
                      throws IOException

Read a protocol from a Json file.

Throws:

IOException

parse

public static Protocol parse(InputStream stream)
                      throws IOException

Read a protocol from a Json stream.

Throws:

IOException

parse

public static Protocol parse(String string)

Read a protocol from a Json string.

main

public static void main(String[] args)
                 throws Exception

Throws:

Exception