Interface Message
- All Known Subinterfaces:
BytesMessage
,MapMessage
,ObjectMessage
,StreamMessage
,TextMessage
Message
interface is the root interface of all JMS
messages. It defines the message header and the acknowledge
method used for all messages.
Most message-oriented middleware (MOM) products treat messages as lightweight entities that consist of a header and a body. The header contains fields used for message routing and identification; the body contains the application data being sent.
Within this general form, the definition of a message varies significantly across products. It would be quite difficult for the JMS API to support all of these message models.
With this in mind, the JMS message model has the following goals:
- Provide a single, unified message API
- Provide an API suitable for creating messages that match the format used by provider-native messaging applications
- Support the development of heterogeneous applications that span operating systems, machine architectures, and computer languages
- Support messages containing objects in the Java programming language ("Java objects")
- Support messages containing Extensible Markup Language (XML) pages
JMS messages are composed of the following parts:
- Header - All messages support the same set of header fields. Header fields contain values used by both clients and providers to identify and route messages.
- Properties - Each message contains a built-in facility for supporting application-defined property values. Properties provide an efficient mechanism for supporting application-defined message filtering.
- Body - The JMS API defines several types of message body, which cover the majority of messaging styles currently in use.
Message Bodies
The JMS API defines five types of message body:
- Stream - A
StreamMessage
object's message body contains a stream of primitive values in the Java programming language ("Java primitives"). It is filled and read sequentially. - Map - A
MapMessage
object's message body contains a set of name-value pairs, where names areString
objects, and values are Java primitives. The entries can be accessed sequentially or randomly by name. The order of the entries is undefined. - Text - A
TextMessage
object's message body contains ajava.lang.String
object. This message type can be used to transport plain-text messages, and XML messages. - Object - An
ObjectMessage
object's message body contains aSerializable
Java object. - Bytes - A
BytesMessage
object's message body contains a stream of uninterpreted bytes. This message type is for literally encoding a body to match an existing message format. In many cases, it is possible to use one of the other body types, which are easier to use. Although the JMS API allows the use of message properties with byte messages, they are typically not used, since the inclusion of properties may affect the format.
Message Headers
The JMSCorrelationID
header field is used for linking one
message with
another. It typically links a reply message with its requesting message.
JMSCorrelationID
can hold a provider-specific message ID,
an application-specific String
object, or a provider-native
byte[]
value.
Message Properties
A Message
object contains a built-in facility for supporting
application-defined property values. In effect, this provides a mechanism
for adding application-specific header fields to a message.
Properties allow an application, via message selectors, to have a JMS provider select, or filter, messages on its behalf using application-specific criteria.
Property names must obey the rules for a message selector identifier.
Property names must not be null, and must not be empty strings. If a property
name is set and it is either null or an empty string, an
IllegalArgumentException
must be thrown.
Property values can be boolean
, byte
,
short
, int
, long
, float
,
double
, and String
.
Property values are set prior to sending a message. When a client
receives a message, its properties are in read-only mode. If a
client attempts to set properties at this point, a
MessageNotWriteableException
is thrown. If
clearProperties
is called, the properties can now be both
read from and written to. Note that header fields are distinct from
properties. Header fields are never in read-only mode.
A property value may duplicate a value in a message's body, or it may not. Although JMS does not define a policy for what should or should not be made a property, application developers should note that JMS providers will likely handle data in a message's body more efficiently than data in a message's properties. For best performance, applications should use message properties only when they need to customize a message's header. The primary reason for doing this is to support customized message selection.
Message properties support the following conversion table. The marked
cases must be supported. The unmarked cases must throw a
JMSException
. The String
-to-primitive conversions
may throw a runtime exception if the
primitive's valueOf
method does not accept the
String
as a valid representation of the primitive.
A value written as the row type can be read as the column type.
| | boolean byte short int long float double String |---------------------------------------------------------- |boolean | X X |byte | X X X X X |short | X X X X |int | X X X |long | X X |float | X X X |double | X X |String | X X X X X X X X |----------------------------------------------------------
In addition to the type-specific set/get methods for properties, JMS
provides the setObjectProperty
and
getObjectProperty
methods. These support the same set of
property types using the objectified primitive values. Their purpose is
to allow the decision of property type to made at execution time rather
than at compile time. They support the same property value conversions.
The setObjectProperty
method accepts values of class
Boolean
, Byte
, Short
,
Integer
, Long
, Float
,
Double
, and String
. An attempt
to use any other class must throw a JMSException
.
The getObjectProperty
method only returns values of class
Boolean
, Byte
, Short
,
Integer
, Long
, Float
,
Double
, and String
.
The order of property values is not defined. To iterate through a
message's property values, use getPropertyNames
to retrieve
a property name enumeration and then use the various property get methods
to retrieve their values.
A message's properties are deleted by the clearProperties
method. This leaves the message with an empty set of properties.
Getting a property value for a name which has not been set returns a
null value. Only the getStringProperty
and
getObjectProperty
methods can return a null value.
Attempting to read a null value as a primitive type must be treated as
calling the primitive's corresponding valueOf(String)
conversion method with a null value.
The JMS API reserves the JMSX
property name prefix for JMS
defined properties.
The full set of these properties is defined in the Java Message Service
specification. The specification also defines whether support for each
property is mandatory or optional.
New JMS defined properties may be added in later versions
of the JMS API. The
String[] ConnectionMetaData.getJMSXPropertyNames
method
returns the names of the JMSX properties supported by a connection.
JMSX properties may be referenced in message selectors whether or not they are supported by a connection. If they are not present in a message, they are treated like any other absent property. The effect of setting a message selector on a property which is set by the provider on receive is undefined.
JMSX properties defined in the specification as "set by provider on send" are available to both the producer and the consumers of the message. JMSX properties defined in the specification as "set by provider on receive" are available only to the consumers.
JMSXGroupID
and JMSXGroupSeq
are standard
properties that clients
should use if they want to group messages. All providers must support them.
Unless specifically noted, the values and semantics of the JMSX properties
are undefined.
The JMS API reserves the JMS_<I>vendor_name</I>
property
name prefix for provider-specific properties. Each provider defines its own
value for <I>vendor_name</I>
. This is the mechanism a JMS
provider uses to make its special per-message services available to a JMS
client.
The purpose of provider-specific properties is to provide special features needed to integrate JMS clients with provider-native clients in a single JMS application. They should not be used for messaging between JMS clients.
Provider Implementations of JMS Message Interfaces
The JMS API provides a set of message interfaces that define the JMS message model. It does not provide implementations of these interfaces.
Each JMS provider supplies a set of message factories with its
Session
object for creating instances of messages. This allows
a provider to use message implementations tailored to its specific needs.
A provider must be prepared to accept message implementations that are not its own. They may not be handled as efficiently as its own implementation; however, they must be handled.
Note the following exception case when a provider is handling a foreign
message implementation. If the foreign message implementation contains a
JMSReplyTo
header field that is set to a foreign destination
implementation, the provider is not required to handle or preserve the
value of this header field.
Message Selectors
A JMS message selector allows a client to specify, by
header field references and property references, the
messages it is interested in. Only messages whose header
and property values
match the
selector are delivered. What it means for a message not to be delivered
depends on the MessageConsumer
being used (see
QueueReceiver
and
TopicSubscriber
).
Message selectors cannot reference message body values.
A message selector matches a message if the selector evaluates to true when the message's header field values and property values are substituted for their corresponding identifiers in the selector.
A message selector is a String
whose syntax is based on a
subset of
the SQL92 conditional expression syntax. If the value of a message selector
is an empty string, the value is treated as a null and indicates that there
is no message selector for the message consumer.
The order of evaluation of a message selector is from left to right within precedence level. Parentheses can be used to change this order.
Predefined selector literals and operator names are shown here in uppercase; however, they are case insensitive.
A selector can contain:
- Literals:
- A string literal is enclosed in single quotes, with a single quote
represented by doubled single quote; for example,
'literal'
and'literal''s'
. Like string literals in the Java programming language, these use the Unicode character encoding. - An exact numeric literal is a numeric value without a decimal
point, such as
57
,-957
, and+62
; numbers in the range oflong
are supported. Exact numeric literals use the integer literal syntax of the Java programming language. - An approximate numeric literal is a numeric value in scientific
notation, such as
7E3
and-57.9E2
, or a numeric value with a decimal, such as7.
,-95.7
, and+6.2
; numbers in the range ofdouble
are supported. Approximate literals use the floating-point literal syntax of the Java programming language. - The boolean literals
TRUE
andFALSE
.
- A string literal is enclosed in single quotes, with a single quote
represented by doubled single quote; for example,
- Identifiers:
- An identifier is an unlimited-length sequence of letters
and digits, the first of which must be a letter. A letter is any
character for which the method
Character.isJavaLetter
returns true. This includes'_'
and'$'
. A letter or digit is any character for which the methodCharacter.isJavaLetterOrDigit
returns true. - Identifiers cannot be the names
NULL
,TRUE
, andFALSE
. - Identifiers cannot be
NOT
,AND
,OR
,BETWEEN
,LIKE
,IN
,IS
, orESCAPE
. - Identifiers are either header field references or property
references. The type of a property value in a message selector
corresponds to the type used to set the property. If a property
that does not exist in a message is referenced, its value is
NULL
. - The conversions that apply to the get methods for properties do not
apply when a property is used in a message selector expression.
For example, suppose you set a property as a string value, as in the
following:
myMessage.setStringProperty("NumberOfOrders", "2");
The following expression in a message selector would evaluate to false, because a string cannot be used in an arithmetic expression:"NumberOfOrders > 1"
- Identifiers are case-sensitive.
- Message header field references are restricted to
JMSDeliveryMode
,JMSPriority
,JMSMessageID
,JMSTimestamp
,JMSCorrelationID
, andJMSType
.JMSMessageID
,JMSCorrelationID
, andJMSType
values may be null and if so are treated as aNULL
value. - Any name beginning with
'JMSX'
is a JMS defined property name. - Any name beginning with
'JMS_'
is a provider-specific property name. - Any name that does not begin with
'JMS'
is an application-specific property name.
- An identifier is an unlimited-length sequence of letters
and digits, the first of which must be a letter. A letter is any
character for which the method
- White space is the same as that defined for the Java programming language: space, horizontal tab, form feed, and line terminator.
- Expressions:
- A selector is a conditional expression; a selector that evaluates
to
true
matches; a selector that evaluates tofalse
or unknown does not match. - Arithmetic expressions are composed of themselves, arithmetic operations, identifiers (whose value is treated as a numeric literal), and numeric literals.
- Conditional expressions are composed of themselves, comparison operations, and logical operations.
- A selector is a conditional expression; a selector that evaluates
to
- Standard bracketing
()
for ordering expression evaluation is supported. - Logical operators in precedence order:
NOT
,AND
,OR
- Comparison operators:
=
,>
,>=
,<
,<=
,<>
(not equal)- Only like type values can be compared. One exception is that it
is valid to compare exact numeric values and approximate numeric
values; the type conversion required is defined by the rules of
numeric promotion in the Java programming language. If the
comparison of non-like type values is attempted, the value of the
operation is false. If either of the type values evaluates to
NULL
, the value of the expression is unknown. - String and boolean comparison is restricted to
=
and<>
. Two strings are equal if and only if they contain the same sequence of characters.
- Only like type values can be compared. One exception is that it
is valid to compare exact numeric values and approximate numeric
values; the type conversion required is defined by the rules of
numeric promotion in the Java programming language. If the
comparison of non-like type values is attempted, the value of the
operation is false. If either of the type values evaluates to
- Arithmetic operators in precedence order:
+
,-
(unary)*
,/
(multiplication and division)+
,-
(addition and subtraction)- Arithmetic operations must use numeric promotion in the Java programming language.
<I>arithmetic-expr1</I> [NOT] BETWEEN <I>arithmetic-expr2</I> AND <I>arithmetic-expr3</I>
(comparison operator)"age BETWEEN 15 AND 19"
is equivalent to"age >= 15 AND age <= 19"
"age NOT BETWEEN 15 AND 19"
is equivalent to"age < 15 OR age > 19"
<I>identifier</I> [NOT] IN (<I>string-literal1</I>, <I>string-literal2</I>,...)
(comparison operator where<I>identifier</I>
has aString
orNULL
value)"Country IN (' UK', 'US', 'France')"
is true for'UK'
and false for'Peru'
; it is equivalent to the expression"(Country = ' UK') OR (Country = ' US') OR (Country = ' France')"
"Country NOT IN (' UK', 'US', 'France')"
is false for'UK'
and true for'Peru'
; it is equivalent to the expression"NOT ((Country = ' UK') OR (Country = ' US') OR (Country = ' France'))"
- If identifier of an
IN
orNOT IN
operation isNULL
, the value of the operation is unknown.
<I>identifier</I> [NOT] LIKE <I>pattern-value</I> [ESCAPE <I>escape-character</I>]
(comparison operator, where<I>identifier</I>
has aString
value;<I>pattern-value</I>
is a string literal where'_'
stands for any single character;'%'
stands for any sequence of characters, including the empty sequence; and all other characters stand for themselves. The optional<I>escape-character</I>
is a single-character string literal whose character is used to escape the special meaning of the'_'
and'%'
in<I>pattern-value</I>
.)"phone LIKE '12%3'"
is true for'123'
or'12993'
and false for'1234'
"word LIKE 'l_se'"
is true for'lose'
and false for'loose'
"underscored LIKE '\_%' ESCAPE '\'"
is true for'_foo'
and false for'bar'
"phone NOT LIKE '12%3'"
is false for'123'
or'12993'
and true for'1234'
- If
<I>identifier</I>
of aLIKE
orNOT LIKE
operation isNULL
, the value of the operation is unknown.
<I>identifier</I> IS NULL
(comparison operator that tests for a null header field value or a missing property value)"prop_name IS NULL"
<I>identifier</I> IS NOT NULL
(comparison operator that tests for the existence of a non-null header field value or a property value)"prop_name IS NOT NULL"
JMS providers are required to verify the syntactic correctness of a message selector at the time it is presented. A method that provides a syntactically incorrect selector must result in a
JMSException
. JMS providers may also optionally provide some semantic checking at the time the selector is presented. Not all semantic checking can be performed at the time a message selector is presented, because property types are not known.The following message selector selects messages with a message type of car and color of blue and weight greater than 2500 pounds:
"JMSType = 'car' AND color = 'blue' AND weight > 2500"
Null Values
As noted above, property values may be
NULL
. The evaluation of selector expressions containingNULL
values is defined by SQL92NULL
semantics. A brief description of these semantics is provided here.SQL treats a
NULL
value as unknown. Comparison or arithmetic with an unknown value always yields an unknown value.The
IS NULL
andIS NOT NULL
operators convert an unknown value into the respectiveTRUE
andFALSE
values.The boolean operators use three-valued logic as defined by the following tables:
The definition of the
AND
operator| AND | T | F | U +------+-------+-------+------- | T | T | F | U | F | F | F | F | U | U | F | U +------+-------+-------+-------
The definition of the
OR
operator| OR | T | F | U +------+-------+-------+-------- | T | T | T | T | F | T | F | U | U | T | U | U +------+-------+-------+-------
The definition of the
NOT
operator| NOT +------+------ | T | F | F | T | U | U +------+-------
Special Notes
When used in a message selector, the
JMSDeliveryMode
header field is treated as having the values'PERSISTENT'
and'NON_PERSISTENT'
.Date and time values should use the standard
long
millisecond value. When a date or time literal is included in a message selector, it should be an integer literal for a millisecond value. The standard way to produce millisecond values is to usejava.util.Calendar
.Although SQL supports fixed decimal comparison and arithmetic, JMS message selectors do not. This is the reason for restricting exact numeric literals to those without a decimal (and the addition of numerics with a decimal as an alternate representation for approximate numeric values).
SQL comments are not supported.
-
Field Summary
Modifier and TypeFieldDescriptionstatic final long
The message producer's default delivery delay is zero.static final int
The message producer's default delivery mode isPERSISTENT
.static final int
The message producer's default priority is 4.static final long
The message producer's default time to live is unlimited; the message never expires. -
Method Summary
Modifier and TypeMethodDescriptionvoid
Acknowledges all consumed messages of the session of this consumed message.void
Clears out the message body.void
Clears a message's properties.<T> T
Returns the message body as an object of the specified type.boolean
getBooleanProperty
(String name) Returns the value of theboolean
property with the specified name.byte
getByteProperty
(String name) Returns the value of thebyte
property with the specified name.double
getDoubleProperty
(String name) Returns the value of thedouble
property with the specified name.float
getFloatProperty
(String name) Returns the value of thefloat
property with the specified name.int
getIntProperty
(String name) Returns the value of theint
property with the specified name.Gets the correlation ID for the message.byte[]
Gets the correlation ID as an array of bytes for the message.int
Gets theDeliveryMode
value specified for this message.long
Gets the message's delivery time value.Gets theDestination
object for this message.long
Gets the message's expiration time.Gets the message ID.int
Gets the message priority level.boolean
Gets an indication of whether this message is being redelivered.Gets theDestination
object to which a reply to this message should be sent.long
Gets the message timestamp.Gets the message type identifier supplied by the client when the message was sent.long
getLongProperty
(String name) Returns the value of thelong
property with the specified name.getObjectProperty
(String name) Returns the value of the Java object property with the specified name.Returns anEnumeration
of all the property names.short
getShortProperty
(String name) Returns the value of theshort
property with the specified name.getStringProperty
(String name) Returns the value of theString
property with the specified name.boolean
Returns whether the message body is capable of being assigned to the specified type.boolean
propertyExists
(String name) Indicates whether a property value exists.void
setBooleanProperty
(String name, boolean value) Sets aboolean
property value with the specified name into the message.void
setByteProperty
(String name, byte value) Sets abyte
property value with the specified name into the message.void
setDoubleProperty
(String name, double value) Sets adouble
property value with the specified name into the message.void
setFloatProperty
(String name, float value) Sets afloat
property value with the specified name into the message.void
setIntProperty
(String name, int value) Sets anint
property value with the specified name into the message.void
setJMSCorrelationID
(String correlationID) Sets the correlation ID for the message.void
setJMSCorrelationIDAsBytes
(byte[] correlationID) Sets the correlation ID as an array of bytes for the message.void
setJMSDeliveryMode
(int deliveryMode) Sets theDeliveryMode
value for this message.void
setJMSDeliveryTime
(long deliveryTime) Sets the message's delivery time value.void
setJMSDestination
(Destination destination) Sets theDestination
object for this message.void
setJMSExpiration
(long expiration) Sets the message's expiration value.void
Sets the message ID.void
setJMSPriority
(int priority) Sets the priority level for this message.void
setJMSRedelivered
(boolean redelivered) Specifies whether this message is being redelivered.void
setJMSReplyTo
(Destination replyTo) Sets theDestination
object to which a reply to this message should be sent.void
setJMSTimestamp
(long timestamp) Sets the message timestamp.void
setJMSType
(String type) Sets the message type.void
setLongProperty
(String name, long value) Sets along
property value with the specified name into the message.void
setObjectProperty
(String name, Object value) Sets a Java object property value with the specified name into the message.void
setShortProperty
(String name, short value) Sets ashort
property value with the specified name into the message.void
setStringProperty
(String name, String value) Sets aString
property value with the specified name into the message.
-
Field Details
-
DEFAULT_DELIVERY_MODE
static final int DEFAULT_DELIVERY_MODEThe message producer's default delivery mode isPERSISTENT
.- See Also:
-
DEFAULT_PRIORITY
static final int DEFAULT_PRIORITYThe message producer's default priority is 4.- See Also:
-
DEFAULT_TIME_TO_LIVE
static final long DEFAULT_TIME_TO_LIVEThe message producer's default time to live is unlimited; the message never expires.- See Also:
-
DEFAULT_DELIVERY_DELAY
static final long DEFAULT_DELIVERY_DELAYThe message producer's default delivery delay is zero.- Since:
- JMS 2.0
- See Also:
-
-
Method Details
-
getJMSMessageID
Gets the message ID.The
JMSMessageID
header field contains a value that uniquely identifies each message sent by a provider.When a message is sent,
JMSMessageID
can be ignored. When thesend
orpublish
method returns, it contains a provider-assigned value.A
JMSMessageID
is aString
value that should function as a unique key for identifying messages in a historical repository. The exact scope of uniqueness is provider-defined. It should at least cover all messages for a specific installation of a provider, where an installation is some connected set of message routers.All
JMSMessageID
values must start with the prefix'ID:'
. Uniqueness of message ID values across different providers is not required.Since message IDs take some effort to create and increase a message's size, some JMS providers may be able to optimize message overhead if they are given a hint that the message ID is not used by an application. By calling the
MessageProducer.setDisableMessageID
method, a JMS client enables this potential optimization for all messages sent by that message producer. If the JMS provider accepts this hint, these messages must have the message ID set to null; if the provider ignores the hint, the message ID must be set to its normal unique value.- Returns:
- the message ID
- Throws:
JMSException
- if the JMS provider fails to get the message ID due to some internal error.- See Also:
-
setJMSMessageID
Sets the message ID.This method is for use by JMS providers only to set this field when a message is sent. This message cannot be used by clients to configure the message ID. This method is public to allow a JMS provider to set this field when sending a message whose implementation is not its own.
- Parameters:
id
- the ID of the message- Throws:
JMSException
- if the JMS provider fails to set the message ID due to some internal error.- See Also:
-
getJMSTimestamp
Gets the message timestamp.The
JMSTimestamp
header field contains the time a message was handed off to a provider to be sent. It is not the time the message was actually transmitted, because the actual send may occur later due to transactions or other client-side queueing of messages.When a message is sent,
JMSTimestamp
is ignored. When thesend
orpublish
method returns, it contains a time value somewhere in the interval between the call and the return. The value is in the format of a normal millis time value in the Java programming language.Since timestamps take some effort to create and increase a message's size, some JMS providers may be able to optimize message overhead if they are given a hint that the timestamp is not used by an application. By calling the
MessageProducer.setDisableMessageTimestamp
method, a JMS client enables this potential optimization for all messages sent by that message producer. If the JMS provider accepts this hint, these messages must have the timestamp set to zero; if the provider ignores the hint, the timestamp must be set to its normal value.- Returns:
- the message timestamp
- Throws:
JMSException
- if the JMS provider fails to get the timestamp due to some internal error.- See Also:
-
setJMSTimestamp
Sets the message timestamp.This method is for use by JMS providers only to set this field when a message is sent. This message cannot be used by clients to configure the message timestamp. This method is public to allow a JMS provider to set this field when sending a message whose implementation is not its own.
- Parameters:
timestamp
- the timestamp for this message- Throws:
JMSException
- if the JMS provider fails to set the timestamp due to some internal error.- See Also:
-
getJMSCorrelationIDAsBytes
Gets the correlation ID as an array of bytes for the message.The use of a
byte[]
value forJMSCorrelationID
is non-portable.- Returns:
- the correlation ID of a message as an array of bytes
- Throws:
JMSException
- if the JMS provider fails to get the correlation ID due to some internal error.- See Also:
-
setJMSCorrelationIDAsBytes
Sets the correlation ID as an array of bytes for the message.The array is copied before the method returns, so future modifications to the array will not alter this message header.
If a provider supports the native concept of correlation ID, a JMS client may need to assign specific
JMSCorrelationID
values to match those expected by native messaging clients. JMS providers without native correlation ID values are not required to support this method and its corresponding get method; their implementation may throw ajava.lang.UnsupportedOperationException
.The use of a
byte[]
value forJMSCorrelationID
is non-portable.- Parameters:
correlationID
- the correlation ID value as an array of bytes- Throws:
JMSException
- if the JMS provider fails to set the correlation ID due to some internal error.- See Also:
-
setJMSCorrelationID
Sets the correlation ID for the message.A client can use the
JMSCorrelationID
header field to link one message with another. A typical use is to link a response message with its request message.JMSCorrelationID
can hold one of the following:- A provider-specific message ID
- An application-specific
String
- A provider-native
byte[]
value
Since each message sent by a JMS provider is assigned a message ID value, it is convenient to link messages via message ID. All message ID values must start with the
'ID:'
prefix.In some cases, an application (made up of several clients) needs to use an application-specific value for linking messages. For instance, an application may use
JMSCorrelationID
to hold a value referencing some external information. Application-specified values must not start with the'ID:'
prefix; this is reserved for provider-generated message ID values.If a provider supports the native concept of correlation ID, a JMS client may need to assign specific
JMSCorrelationID
values to match those expected by clients that do not use the JMS API. Abyte[]
value is used for this purpose. JMS providers without native correlation ID values are not required to supportbyte[]
values. The use of abyte[]
value forJMSCorrelationID
is non-portable.- Parameters:
correlationID
- the message ID of a message being referred to- Throws:
JMSException
- if the JMS provider fails to set the correlation ID due to some internal error.- See Also:
-
getJMSCorrelationID
Gets the correlation ID for the message.This method is used to return correlation ID values that are either provider-specific message IDs or application-specific
String
values.- Returns:
- the correlation ID of a message as a
String
- Throws:
JMSException
- if the JMS provider fails to get the correlation ID due to some internal error.- See Also:
-
getJMSReplyTo
Gets theDestination
object to which a reply to this message should be sent.- Returns:
Destination
to which to send a response to this message- Throws:
JMSException
- if the JMS provider fails to get theJMSReplyTo
destination due to some internal error.- See Also:
-
setJMSReplyTo
Sets theDestination
object to which a reply to this message should be sent.The
JMSReplyTo
header field contains the destination where a reply to the current message should be sent. If it is null, no reply is expected. The destination may be either aQueue
object or aTopic
object.Messages sent with a null
JMSReplyTo
value may be a notification of some event, or they may just be some data the sender thinks is of interest.Messages with a
JMSReplyTo
value typically expect a response. A response is optional; it is up to the client to decide. These messages are called requests. A message sent in response to a request is called a reply.In some cases a client may wish to match a request it sent earlier with a reply it has just received. The client can use the
JMSCorrelationID
header field for this purpose.- Parameters:
replyTo
-Destination
to which to send a response to this message- Throws:
JMSException
- if the JMS provider fails to set theJMSReplyTo
destination due to some internal error.- See Also:
-
getJMSDestination
Gets theDestination
object for this message.The
JMSDestination
header field contains the destination to which the message is being sent.When a message is sent, this field is ignored. After completion of the
send
orpublish
method, the field holds the destination specified by the method.When a message is received, its
JMSDestination
value must be equivalent to the value assigned when it was sent.- Returns:
- the destination of this message
- Throws:
JMSException
- if the JMS provider fails to get the destination due to some internal error.- See Also:
-
setJMSDestination
Sets theDestination
object for this message.This method is for use by JMS providers only to set this field when a message is sent. This message cannot be used by clients to configure the destination of the message. This method is public to allow a JMS provider to set this field when sending a message whose implementation is not its own.
- Parameters:
destination
- the destination for this message- Throws:
JMSException
- if the JMS provider fails to set the destination due to some internal error.- See Also:
-
getJMSDeliveryMode
Gets theDeliveryMode
value specified for this message.- Returns:
- the delivery mode for this message
- Throws:
JMSException
- if the JMS provider fails to get the delivery mode due to some internal error.- See Also:
-
setJMSDeliveryMode
Sets theDeliveryMode
value for this message.This method is for use by JMS providers only to set this field when a message is sent. This message cannot be used by clients to configure the delivery mode of the message. This method is public to allow a JMS provider to set this field when sending a message whose implementation is not its own.
- Parameters:
deliveryMode
- the delivery mode for this message- Throws:
JMSException
- if the JMS provider fails to set the delivery mode due to some internal error.- See Also:
-
getJMSRedelivered
Gets an indication of whether this message is being redelivered.If a client receives a message with the
JMSRedelivered
field set, it is likely, but not guaranteed, that this message was delivered earlier but that its receipt was not acknowledged at that time.- Returns:
- true if this message is being redelivered
- Throws:
JMSException
- if the JMS provider fails to get the redelivered state due to some internal error.- See Also:
-
setJMSRedelivered
Specifies whether this message is being redelivered.This method is for use by JMS providers only to set this field when a message is delivered. This message cannot be used by clients to configure the redelivered status of the message. This method is public to allow a JMS provider to set this field when sending a message whose implementation is not its own.
- Parameters:
redelivered
- an indication of whether this message is being redelivered- Throws:
JMSException
- if the JMS provider fails to set the redelivered state due to some internal error.- See Also:
-
getJMSType
Gets the message type identifier supplied by the client when the message was sent.- Returns:
- the message type
- Throws:
JMSException
- if the JMS provider fails to get the message type due to some internal error.- See Also:
-
setJMSType
Sets the message type.Some JMS providers use a message repository that contains the definitions of messages sent by applications. The
JMSType
header field may reference a message's definition in the provider's repository.The JMS API does not define a standard message definition repository, nor does it define a naming policy for the definitions it contains.
Some messaging systems require that a message type definition for each application message be created and that each message specify its type. In order to work with such JMS providers, JMS clients should assign a value to
JMSType
, whether the application makes use of it or not. This ensures that the field is properly set for those providers that require it.To ensure portability, JMS clients should use symbolic values for
JMSType
that can be configured at installation time to the values defined in the current provider's message repository. If string literals are used, they may not be valid type names for some JMS providers.- Parameters:
type
- the message type- Throws:
JMSException
- if the JMS provider fails to set the message type due to some internal error.- See Also:
-
getJMSExpiration
Gets the message's expiration time.When a message is sent, the
JMSExpiration
header field is left unassigned. After completion of thesend
orpublish
method, it holds the expiration time of the message. This is the the difference, measured in milliseconds, between the expiration time and midnight, January 1, 1970 UTC.If the time-to-live is specified as zero,
JMSExpiration
is set to zero to indicate that the message does not expire.When a message's expiration time is reached, a provider should discard it. The JMS API does not define any form of notification of message expiration.
Clients should not receive messages that have expired; however, the JMS API does not guarantee that this will not happen.
- Returns:
- the message's expiration time value
- Throws:
JMSException
- if the JMS provider fails to get the message expiration due to some internal error.- See Also:
-
setJMSExpiration
Sets the message's expiration value.This method is for use by JMS providers only to set this field when a message is sent. This message cannot be used by clients to configure the expiration time of the message. This method is public to allow a JMS provider to set this field when sending a message whose implementation is not its own.
- Parameters:
expiration
- the message's expiration time- Throws:
JMSException
- if the JMS provider fails to set the message expiration due to some internal error.- See Also:
-
getJMSDeliveryTime
Gets the message's delivery time value.When a message is sent, the
JMSDeliveryTime
header field is left unassigned. After completion of thesend
orpublish
method, it holds the delivery time of the message. This is the the difference, measured in milliseconds, between the delivery time and midnight, January 1, 1970 UTC.A message's delivery time is the earliest time when a JMS provider may deliver the message to a consumer. The provider must not deliver messages before the delivery time has been reached.
- Returns:
- the message's delivery time value
- Throws:
JMSException
- if the JMS provider fails to get the delivery time due to some internal error.- Since:
- JMS 2.0
- See Also:
-
setJMSDeliveryTime
Sets the message's delivery time value.This method is for use by JMS providers only to set this field when a message is sent. This message cannot be used by clients to configure the delivery time of the message. This method is public to allow a JMS provider to set this field when sending a message whose implementation is not its own.
- Parameters:
deliveryTime
- the message's delivery time value- Throws:
JMSException
- if the JMS provider fails to set the delivery time due to some internal error.- Since:
- JMS 2.0
- See Also:
-
getJMSPriority
Gets the message priority level.The JMS API defines ten levels of priority value, with 0 as the lowest priority and 9 as the highest. In addition, clients should consider priorities 0-4 as gradations of normal priority and priorities 5-9 as gradations of expedited priority.
The JMS API does not require that a provider strictly implement priority ordering of messages; however, it should do its best to deliver expedited messages ahead of normal messages.
- Returns:
- the default message priority
- Throws:
JMSException
- if the JMS provider fails to get the message priority due to some internal error.- See Also:
-
setJMSPriority
Sets the priority level for this message.This method is for use by JMS providers only to set this field when a message is sent. This message cannot be used by clients to configure the priority level of the message. This method is public to allow a JMS provider to set this field when sending a message whose implementation is not its own.
- Parameters:
priority
- the priority of this message- Throws:
JMSException
- if the JMS provider fails to set the message priority due to some internal error.- See Also:
-
clearProperties
Clears a message's properties.The message's header fields and body are not cleared.
- Throws:
JMSException
- if the JMS provider fails to clear the message properties due to some internal error.
-
propertyExists
Indicates whether a property value exists.- Parameters:
name
- the name of the property to test- Returns:
- true if the property exists
- Throws:
JMSException
- if the JMS provider fails to determine if the property exists due to some internal error.
-
getBooleanProperty
Returns the value of theboolean
property with the specified name.- Parameters:
name
- the name of theboolean
property- Returns:
- the
boolean
property value for the specified name - Throws:
JMSException
- if the JMS provider fails to get the property value due to some internal error.MessageFormatException
- if this type conversion is invalid.
-
getByteProperty
Returns the value of thebyte
property with the specified name.- Parameters:
name
- the name of thebyte
property- Returns:
- the
byte
property value for the specified name - Throws:
JMSException
- if the JMS provider fails to get the property value due to some internal error.MessageFormatException
- if this type conversion is invalid.
-
getShortProperty
Returns the value of theshort
property with the specified name.- Parameters:
name
- the name of theshort
property- Returns:
- the
short
property value for the specified name - Throws:
JMSException
- if the JMS provider fails to get the property value due to some internal error.MessageFormatException
- if this type conversion is invalid.
-
getIntProperty
Returns the value of theint
property with the specified name.- Parameters:
name
- the name of theint
property- Returns:
- the
int
property value for the specified name - Throws:
JMSException
- if the JMS provider fails to get the property value due to some internal error.MessageFormatException
- if this type conversion is invalid.
-
getLongProperty
Returns the value of thelong
property with the specified name.- Parameters:
name
- the name of thelong
property- Returns:
- the
long
property value for the specified name - Throws:
JMSException
- if the JMS provider fails to get the property value due to some internal error.MessageFormatException
- if this type conversion is invalid.
-
getFloatProperty
Returns the value of thefloat
property with the specified name.- Parameters:
name
- the name of thefloat
property- Returns:
- the
float
property value for the specified name - Throws:
JMSException
- if the JMS provider fails to get the property value due to some internal error.MessageFormatException
- if this type conversion is invalid.
-
getDoubleProperty
Returns the value of thedouble
property with the specified name.- Parameters:
name
- the name of thedouble
property- Returns:
- the
double
property value for the specified name - Throws:
JMSException
- if the JMS provider fails to get the property value due to some internal error.MessageFormatException
- if this type conversion is invalid.
-
getStringProperty
Returns the value of theString
property with the specified name.- Parameters:
name
- the name of theString
property- Returns:
- the
String
property value for the specified name; if there is no property by this name, a null value is returned - Throws:
JMSException
- if the JMS provider fails to get the property value due to some internal error.MessageFormatException
- if this type conversion is invalid.
-
getObjectProperty
Returns the value of the Java object property with the specified name.This method can be used to return, in objectified format, an object that has been stored as a property in the message with the equivalent
setObjectProperty
method call, or its equivalent primitiveset<I>type</I>Property
method.- Parameters:
name
- the name of the Java object property- Returns:
- the Java object property value with the specified name, in
objectified format (for example, if the property was set as an
int
, anInteger
is returned); if there is no property by this name, a null value is returned - Throws:
JMSException
- if the JMS provider fails to get the property value due to some internal error.
-
getPropertyNames
Returns anEnumeration
of all the property names.Note that JMS standard header fields are not considered properties and are not returned in this enumeration.
- Returns:
- an enumeration of all the names of property values
- Throws:
JMSException
- if the JMS provider fails to get the property names due to some internal error.
-
setBooleanProperty
Sets aboolean
property value with the specified name into the message.- Parameters:
name
- the name of theboolean
propertyvalue
- theboolean
property value to set- Throws:
JMSException
- if the JMS provider fails to set the property due to some internal error.IllegalArgumentException
- if the name is null or if the name is an empty string.MessageNotWriteableException
- if properties are read-only
-
setByteProperty
Sets abyte
property value with the specified name into the message.- Parameters:
name
- the name of thebyte
propertyvalue
- thebyte
property value to set- Throws:
JMSException
- if the JMS provider fails to set the property due to some internal error.IllegalArgumentException
- if the name is null or if the name is an empty string.MessageNotWriteableException
- if properties are read-only
-
setShortProperty
Sets ashort
property value with the specified name into the message.- Parameters:
name
- the name of theshort
propertyvalue
- theshort
property value to set- Throws:
JMSException
- if the JMS provider fails to set the property due to some internal error.IllegalArgumentException
- if the name is null or if the name is an empty string.MessageNotWriteableException
- if properties are read-only
-
setIntProperty
Sets anint
property value with the specified name into the message.- Parameters:
name
- the name of theint
propertyvalue
- theint
property value to set- Throws:
JMSException
- if the JMS provider fails to set the property due to some internal error.IllegalArgumentException
- if the name is null or if the name is an empty string.MessageNotWriteableException
- if properties are read-only
-
setLongProperty
Sets along
property value with the specified name into the message.- Parameters:
name
- the name of thelong
propertyvalue
- thelong
property value to set- Throws:
JMSException
- if the JMS provider fails to set the property due to some internal error.IllegalArgumentException
- if the name is null or if the name is an empty string.MessageNotWriteableException
- if properties are read-only
-
setFloatProperty
Sets afloat
property value with the specified name into the message.- Parameters:
name
- the name of thefloat
propertyvalue
- thefloat
property value to set- Throws:
JMSException
- if the JMS provider fails to set the property due to some internal error.IllegalArgumentException
- if the name is null or if the name is an empty string.MessageNotWriteableException
- if properties are read-only
-
setDoubleProperty
Sets adouble
property value with the specified name into the message.- Parameters:
name
- the name of thedouble
propertyvalue
- thedouble
property value to set- Throws:
JMSException
- if the JMS provider fails to set the property due to some internal error.IllegalArgumentException
- if the name is null or if the name is an empty string.MessageNotWriteableException
- if properties are read-only
-
setStringProperty
Sets aString
property value with the specified name into the message.- Parameters:
name
- the name of theString
propertyvalue
- theString
property value to set- Throws:
JMSException
- if the JMS provider fails to set the property due to some internal error.IllegalArgumentException
- if the name is null or if the name is an empty string.MessageNotWriteableException
- if properties are read-only
-
setObjectProperty
Sets a Java object property value with the specified name into the message.Note that this method works only for the objectified primitive object types (
Integer
,Double
,Long
...) andString
objects.- Parameters:
name
- the name of the Java object propertyvalue
- the Java object property value to set- Throws:
JMSException
- if the JMS provider fails to set the property due to some internal error.IllegalArgumentException
- if the name is null or if the name is an empty string.MessageFormatException
- if the object is invalidMessageNotWriteableException
- if properties are read-only
-
acknowledge
Acknowledges all consumed messages of the session of this consumed message.All consumed JMS messages support the
acknowledge
method for use when a client has specified that its JMS session's consumed messages are to be explicitly acknowledged. By invokingacknowledge
on a consumed message, a client acknowledges all messages consumed by the session that the message was delivered to.Calls to
acknowledge
are ignored for both transacted sessions and sessions specified to use implicit acknowledgement modes.A client may individually acknowledge each message as it is consumed, or it may choose to acknowledge messages as an application-defined group (which is done by calling acknowledge on the last received message of the group, thereby acknowledging all messages consumed by the session.)
Messages that have been received but not acknowledged may be redelivered.
- Throws:
JMSException
- if the JMS provider fails to acknowledge the messages due to some internal error.IllegalStateException
- if this method is called on a closed session.- See Also:
-
clearBody
Clears out the message body. Clearing a message's body does not clear its header values or property entries.If this message body was read-only, calling this method leaves the message body in the same state as an empty body in a newly created message.
- Throws:
JMSException
- if the JMS provider fails to clear the message body due to some internal error.
-
getBody
Returns the message body as an object of the specified type. This method may be called on any type of message except for StreamMessage. The message body must be capable of being assigned to the specified type. This means that the specified class or interface must be either the same as, or a superclass or superinterface of, the class of the message body. If the message has no body then any type may be specified and null is returned.- Parameters:
c
- The type to which the message body will be assigned.
If the message is aTextMessage
then this parameter must be set toString.class
or another type to which aString
is assignable.
If the message is aObjectMessage
then parameter must must be set tojava.io.Serializable.class
or another type to which the body is assignable.
If the message is aMapMessage
then this parameter must be set tojava.util.Map.class
(orjava.lang.Object.class
).
If the message is aBytesMessage
then this parameter must be set tobyte[].class
(orjava.lang.Object.class
). This method will reset theBytesMessage
before and after use.
If the message is aTextMessage
,ObjectMessage
,MapMessage
orBytesMessage
and the message has no body, then the above does not apply and this parameter may be set to any type; the returned value will always be null.
If the message is aMessage
(but not one of its subtypes) then this parameter may be set to any type; the returned value will always be null.- Returns:
- the message body
- Throws:
MessageFormatException
-- if the message is a
StreamMessage
- if the message body cannot be assigned to the specified type
- if the message is an
ObjectMessage
and object deserialization fails.
- if the message is a
JMSException
- if the JMS provider fails to get the message body due to some internal error.- Since:
- JMS 2.0
-
isBodyAssignableTo
Returns whether the message body is capable of being assigned to the specified type. If this method returns true then a subsequent call to the methodgetBody
on the same message with the same type argument would not throw a MessageFormatException.If the message is a
StreamMessage
then false is always returned. If the message is aObjectMessage
and object deserialization fails then false is returned. If the message has no body then any type may be specified and true is returned.- Parameters:
c
- The specified type
If the message is aTextMessage
then this method will only return true if this parameter is set toString.class
or another type to which aString
is assignable.
If the message is aObjectMessage
then this method will only return true if this parameter is set tojava.io.Serializable.class
or another class to which the body is assignable.
If the message is aMapMessage
then this method will only return true if this parameter is set tojava.util.Map.class
(orjava.lang.Object.class
).
If the message is aBytesMessage
then this this method will only return true if this parameter is set tobyte[].class
(orjava.lang.Object.class
).
If the message is aTextMessage
,ObjectMessage
,MapMessage
orBytesMessage
and the message has no body, then the above does not apply and this method will return true irrespective of the value of this parameter.
If the message is aMessage
(but not one of its subtypes) then this method will return true irrespective of the value of this parameter.- Returns:
- whether the message body is capable of being assigned to the specified type
- Throws:
JMSException
- if the JMS provider fails to return a value due to some internal error.
-