org.springframework.messaging.support

Class MessageBuilder<T>

java.lang.Object

org.springframework.messaging.support.MessageBuilder<T>

Type Parameters:

T - the message payload type

public final class MessageBuilder<T>
extends Object

A builder for creating a GenericMessage (or ErrorMessage if the payload is of type Throwable).

Since:

4.0

Author:

Arjen Poutsma, Mark Fisher, Rossen Stoyanchev

See Also:

GenericMessage, ErrorMessage

Method Summary

Modifier and Type	Method and Description
Message<T>	build()
MessageBuilder<T>	copyHeaders(Map<String,?> headersToCopy) Copy the name-value pairs from the provided Map.
MessageBuilder<T>	copyHeadersIfAbsent(Map<String,?> headersToCopy) Copy the name-value pairs from the provided Map.
static <T> Message<T>	createMessage(T payload, MessageHeaders messageHeaders) A shortcut factory method for creating a message with the given payload and MessageHeaders.
static <T> MessageBuilder<T>	fromMessage(Message<T> message) Create a builder for a new Message instance pre-populated with all of the headers copied from the provided message.
MessageBuilder<T>	removeHeader(String headerName) Remove the value for the given header name.
MessageBuilder<T>	removeHeaders(String... headerPatterns) Removes all headers provided via array of 'headerPatterns'.
MessageBuilder<T>	setErrorChannel(MessageChannel errorChannel)
MessageBuilder<T>	setErrorChannelName(String errorChannelName)
MessageBuilder<T>	setHeader(String headerName, Object headerValue) Set the value for the given header name.
MessageBuilder<T>	setHeaderIfAbsent(String headerName, Object headerValue) Set the value for the given header name only if the header name is not already associated with a value.
MessageBuilder<T>	setHeaders(MessageHeaderAccessor accessor) Set the message headers to use by providing a MessageHeaderAccessor.
MessageBuilder<T>	setReplyChannel(MessageChannel replyChannel)
MessageBuilder<T>	setReplyChannelName(String replyChannelName)
static <T> MessageBuilder<T>	withPayload(T payload) Create a new builder for a message with the given payload.

Methods inherited from class java.lang.Object

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

Method Detail

setHeaders

public MessageBuilder<T> setHeaders(MessageHeaderAccessor accessor)

Set the message headers to use by providing a MessageHeaderAccessor.

Parameters:

accessor - the headers to use

setHeader

public MessageBuilder<T> setHeader(String headerName,
                                   @Nullable
                                   Object headerValue)

Set the value for the given header name. If the provided value is null, the header will be removed.

setHeaderIfAbsent

public MessageBuilder<T> setHeaderIfAbsent(String headerName,
                                           Object headerValue)

Set the value for the given header name only if the header name is not already associated with a value.

removeHeaders

public MessageBuilder<T> removeHeaders(String... headerPatterns)

Removes all headers provided via array of 'headerPatterns'. As the name suggests the array may contain simple matching patterns for header names. Supported pattern styles are: "xxx*", "*xxx", "*xxx*" and "xxx*yyy".

removeHeader

public MessageBuilder<T> removeHeader(String headerName)

Remove the value for the given header name.

copyHeaders

public MessageBuilder<T> copyHeaders(@Nullable
                                     Map<String,?> headersToCopy)

Copy the name-value pairs from the provided Map. This operation will overwrite any existing values. Use { copyHeadersIfAbsent(Map) to avoid overwriting values. Note that the 'id' and 'timestamp' header values will never be overwritten.

copyHeadersIfAbsent

public MessageBuilder<T> copyHeadersIfAbsent(@Nullable
                                             Map<String,?> headersToCopy)

Copy the name-value pairs from the provided Map. This operation will not overwrite any existing values.

setReplyChannel

public MessageBuilder<T> setReplyChannel(MessageChannel replyChannel)

setReplyChannelName

public MessageBuilder<T> setReplyChannelName(String replyChannelName)

setErrorChannel

public MessageBuilder<T> setErrorChannel(MessageChannel errorChannel)

setErrorChannelName

public MessageBuilder<T> setErrorChannelName(String errorChannelName)

build

public Message<T> build()

fromMessage

public static <T> MessageBuilder<T> fromMessage(Message<T> message)

Create a builder for a new Message instance pre-populated with all of the headers copied from the provided message. The payload of the provided Message will also be used as the payload for the new message.

Parameters:

message - the Message from which the payload and all headers will be copied

withPayload

public static <T> MessageBuilder<T> withPayload(T payload)

Create a new builder for a message with the given payload.

Parameters:

payload - the payload

createMessage

public static <T> Message<T> createMessage(@Nullable
                                           T payload,
                                           MessageHeaders messageHeaders)

A shortcut factory method for creating a message with the given payload and MessageHeaders.

Note: the given MessageHeaders instance is used directly in the new message, i.e. it is not copied.

Parameters:

payload - the payload to use (never null)

messageHeaders - the headers to use (never null)

Returns:

the created message

Since:

4.1