javax.jms.Message Maven / Gradle / Ivy
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package javax.jms;
import java.util.Enumeration;
/** The {@code Message} interface is the root interface of all JMS
* messages. It defines the message header and the {@code 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 {@code 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 {@code MapMessage} object's message body contains a set
* of name-value pairs, where names are {@code String}
* 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 {@code TextMessage} object's message body contains a
* {@code java.lang.String} object. This message type can be used
* to transport plain-text messages, and XML messages.
*
- Object - An {@code ObjectMessage} object's message body contains
* a {@code Serializable} Java object.
*
- Bytes - A {@code 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 {@code JMSCorrelationID} header field is used for linking one
* message with
* another. It typically links a reply message with its requesting message.
*
*
{@code JMSCorrelationID} can hold a provider-specific message ID,
* an application-specific {@code String} object, or a provider-native
* {@code byte[]} value.
*
*
Message Properties
*
* A {@code 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
* {@code IllegalArgumentException} must be thrown.
*
*
Property values can be {@code boolean}, {@code byte},
* {@code short}, {@code int}, {@code long}, {@code float},
* {@code double}, and {@code 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
* {@code MessageNotWriteableException} is thrown. If
* {@code 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
* {@code JMSException}. The {@code String}-to-primitive conversions
* may throw a runtime exception if the
* primitive's {@code valueOf} method does not accept the
* {@code 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 {@code setObjectProperty} and
* {@code 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 {@code setObjectProperty} method accepts values of class
* {@code Boolean}, {@code Byte}, {@code Short},
* {@code Integer}, {@code Long}, {@code Float},
* {@code Double}, and {@code String}. An attempt
* to use any other class must throw a {@code JMSException}.
*
*
The {@code getObjectProperty} method only returns values of class
* {@code Boolean}, {@code Byte}, {@code Short},
* {@code Integer}, {@code Long}, {@code Float},
* {@code Double}, and {@code String}.
*
*
The order of property values is not defined. To iterate through a
* message's property values, use {@code 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 {@code 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 {@code getStringProperty} and
* {@code 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 {@code valueOf(String)}
* conversion method with a null value.
*
*
The JMS API reserves the {@code 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
* {@code 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.
*
*
{@code JMSXGroupID} and {@code 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_vendor_name property
* name prefix for provider-specific properties. Each provider defines its own
* value for vendor_name. 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
* {@code 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
* {@code 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 {@code MessageConsumer} being used (see
* {@link javax.jms.QueueReceiver QueueReceiver} and
* {@link javax.jms.TopicSubscriber 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 {@code 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,
* {@code 'literal'} and {@code '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 {@code 57}, {@code -957}, and
* {@code +62}; numbers in the range of {@code long} 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 {@code 7E3} and {@code -57.9E2}, or a
* numeric value with a decimal, such as {@code 7.},
* {@code -95.7}, and {@code +6.2}; numbers in the range of
* {@code double} are supported. Approximate literals use the
* floating-point literal syntax of the Java programming language.
*
- The boolean literals {@code TRUE} and {@code FALSE}.
*
* - 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 {@code Character.isJavaLetter}
* returns true. This includes {@code '_'} and {@code '$'}.
* A letter or digit is any character for which the method
* {@code Character.isJavaLetterOrDigit} returns true.
*
- Identifiers cannot be the names {@code NULL},
* {@code TRUE}, and {@code FALSE}.
*
- Identifiers cannot be {@code NOT}, {@code AND},
* {@code OR}, {@code BETWEEN}, {@code LIKE},
* {@code IN}, {@code IS}, or {@code ESCAPE}.
*
- 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
* {@code 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
* {@code JMSDeliveryMode}, {@code JMSPriority},
* {@code JMSMessageID}, {@code JMSTimestamp},
* {@code JMSCorrelationID}, and {@code JMSType}.
* {@code JMSMessageID}, {@code JMSCorrelationID}, and
* {@code JMSType} values may be null and if so are treated as a
* {@code NULL} value.
*
- Any name beginning with {@code 'JMSX'} is a JMS defined
* property name.
*
- Any name beginning with {@code 'JMS_'} is a provider-specific
* property name.
*
- Any name that does not begin with {@code 'JMS'} is an
* application-specific property name.
*
* - 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 {@code true} matches; a selector that evaluates to
* {@code false} 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.
*
* - Standard bracketing {@code ()} for ordering expression evaluation
* is supported.
*
- Logical operators in precedence order: {@code NOT},
* {@code AND}, {@code OR}
*
- Comparison operators: {@code =}, {@code >}, {@code >=},
* {@code <}, {@code <=}, {@code <>} (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
* {@code NULL}, the value of the expression is unknown.
*
- String and boolean comparison is restricted to {@code =} and
* {@code <>}. Two strings are equal
* if and only if they contain the same sequence of characters.
*
* - Arithmetic operators in precedence order:
*
* - {@code +}, {@code -} (unary)
*
- {@code *}, {@code /} (multiplication and division)
*
- {@code +}, {@code -} (addition and subtraction)
*
- Arithmetic operations must use numeric promotion in the Java
* programming language.
*
* arithmetic-expr1 [NOT] BETWEEN arithmetic-expr2
* AND arithmetic-expr3 (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"
*
* identifier [NOT] IN (string-literal1,
* string-literal2,...) (comparison operator where
* identifier has a String or
* NULL 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 or NOT IN
* operation is NULL, the value of the operation is
* unknown.
*
* identifier [NOT] LIKE pattern-value [ESCAPE
* escape-character] (comparison operator, where
* identifier has a String value;
* pattern-value 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
* escape-character is a single-character string
* literal whose character is used to escape the special meaning of the
* '_' and '%' in
* pattern-value.)
*
* "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
identifier of a LIKE or
* NOT LIKE operation is NULL, the value
* of the operation is unknown.
*
* identifier IS NULL (comparison operator that tests
* for a null header field value or a missing property value)
*
* "prop_name IS NULL"
*
* identifier 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 {@code 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 {@code NULL}. The evaluation
* of selector expressions containing {@code NULL} values is defined by
* SQL92 {@code NULL} semantics. A brief description of these semantics
* is provided here.
*
*
SQL treats a {@code NULL} value as unknown. Comparison or arithmetic
* with an unknown value always yields an unknown value.
*
*
The {@code IS NULL} and {@code IS NOT NULL} operators convert
* an unknown value into the respective {@code TRUE} and
* {@code FALSE} values.
*
*
The boolean operators use three-valued logic as defined by the
* following tables:
*
*
The definition of the {@code AND} operator
*
*
* | AND | T | F | U
* +------+-------+-------+-------
* | T | T | F | U
* | F | F | F | F
* | U | U | F | U
* +------+-------+-------+-------
*
*
* The definition of the {@code OR} operator
*
*
* | OR | T | F | U
* +------+-------+-------+--------
* | T | T | T | T
* | F | T | F | U
* | U | T | U | U
* +------+-------+-------+-------
*
*
* The definition of the {@code NOT} operator
*
*
* | NOT
* +------+------
* | T | F
* | F | T
* | U | U
* +------+-------
*
*
* Special Notes
*
* When used in a message selector, the {@code JMSDeliveryMode} header
* field is treated as having the values {@code 'PERSISTENT'} and
* {@code 'NON_PERSISTENT'}.
*
*
Date and time values should use the standard {@code 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 use
* {@code java.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.
*
* @version JMS 2.0
* @since JMS 1.0
*
* @see javax.jms.MessageConsumer#receive()
* @see javax.jms.MessageConsumer#receive(long)
* @see javax.jms.MessageConsumer#receiveNoWait()
* @see javax.jms.MessageListener#onMessage(Message)
* @see javax.jms.BytesMessage
* @see javax.jms.MapMessage
* @see javax.jms.ObjectMessage
* @see javax.jms.StreamMessage
* @see javax.jms.TextMessage
*/
public interface Message {
/** The message producer's default delivery mode is {@code PERSISTENT}.
*
* @see DeliveryMode#PERSISTENT
*/
static final int DEFAULT_DELIVERY_MODE = DeliveryMode.PERSISTENT;
/** The message producer's default priority is 4.
*/
static final int DEFAULT_PRIORITY = 4;
/** The message producer's default time to live is unlimited; the message
* never expires.
*/
static final long DEFAULT_TIME_TO_LIVE = 0;
/** The message producer's default delivery delay is zero.
* @since JMS 2.0
*/
static final long DEFAULT_DELIVERY_DELAY = 0;
/** Gets the message ID.
*
*
The {@code JMSMessageID} header field contains a value that
* uniquely identifies each message sent by a provider.
*
*
When a message is sent, {@code JMSMessageID} can be ignored.
* When the {@code send} or {@code publish} method returns, it
* contains a provider-assigned value.
*
*
A {@code JMSMessageID} is a {@code String} 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 {@code JMSMessageID} values must start with the prefix
* {@code '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
* {@code 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.
*
* @return the message ID
*
* @exception JMSException if the JMS provider fails to get the message ID
* due to some internal error.
* @see javax.jms.Message#setJMSMessageID(String)
* @see javax.jms.MessageProducer#setDisableMessageID(boolean)
*/
String
getJMSMessageID() throws JMSException;
/** 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.
*
* @param id the ID of the message
*
* @exception JMSException if the JMS provider fails to set the message ID
* due to some internal error.
*
* @see javax.jms.Message#getJMSMessageID()
*/
void
setJMSMessageID(String id) throws JMSException;
/** Gets the message timestamp.
*
*
The {@code 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, {@code JMSTimestamp} is ignored. When
* the {@code send} or {@code publish}
* 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
* {@code 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.
*
* @return the message timestamp
*
* @exception JMSException if the JMS provider fails to get the timestamp
* due to some internal error.
*
* @see javax.jms.Message#setJMSTimestamp(long)
* @see javax.jms.MessageProducer#setDisableMessageTimestamp(boolean)
*/
long
getJMSTimestamp() throws JMSException;
/** 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.
*
* @param timestamp the timestamp for this message
*
* @exception JMSException if the JMS provider fails to set the timestamp
* due to some internal error.
*
* @see javax.jms.Message#getJMSTimestamp()
*/
void
setJMSTimestamp(long timestamp) throws JMSException;
/** Gets the correlation ID as an array of bytes for the message.
*
*
The use of a {@code byte[]} value for
* {@code JMSCorrelationID} is non-portable.
*
* @return the correlation ID of a message as an array of bytes
*
* @exception JMSException if the JMS provider fails to get the correlation
* ID due to some internal error.
*
* @see javax.jms.Message#setJMSCorrelationID(String)
* @see javax.jms.Message#getJMSCorrelationID()
* @see javax.jms.Message#setJMSCorrelationIDAsBytes(byte[])
*/
byte []
getJMSCorrelationIDAsBytes() throws JMSException;
/** 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 {@code 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 a
* {@code java.lang.UnsupportedOperationException}.
*
*
The use of a {@code byte[]} value for
* {@code JMSCorrelationID} is non-portable.
*
* @param correlationID the correlation ID value as an array of bytes
*
* @exception JMSException if the JMS provider fails to set the correlation
* ID due to some internal error.
*
* @see javax.jms.Message#setJMSCorrelationID(String)
* @see javax.jms.Message#getJMSCorrelationID()
* @see javax.jms.Message#getJMSCorrelationIDAsBytes()
*/
void
setJMSCorrelationIDAsBytes(byte[] correlationID) throws JMSException;
/** Sets the correlation ID for the message.
*
*
A client can use the {@code JMSCorrelationID} header field to
* link one message with another. A typical use is to link a response
* message with its request message.
*
*
{@code JMSCorrelationID} can hold one of the following:
*
* - A provider-specific message ID
*
- An application-specific {@code String}
*
- A provider-native {@code 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 {@code '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 {@code JMSCorrelationID} to hold a value
* referencing some external information. Application-specified values
* must not start with the {@code '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 {@code JMSCorrelationID} values
* to match those expected by clients that do not use the JMS API. A
* {@code byte[]} value is used for this
* purpose. JMS providers without native correlation ID values are not
* required to support {@code byte[]} values. The use of a
* {@code byte[]} value for {@code JMSCorrelationID} is
* non-portable.
*
* @param correlationID the message ID of a message being referred to
*
* @exception JMSException if the JMS provider fails to set the correlation
* ID due to some internal error.
*
* @see javax.jms.Message#getJMSCorrelationID()
* @see javax.jms.Message#getJMSCorrelationIDAsBytes()
* @see javax.jms.Message#setJMSCorrelationIDAsBytes(byte[])
*/
void
setJMSCorrelationID(String correlationID) throws JMSException;
/** 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
* {@code String} values.
*
* @return the correlation ID of a message as a {@code String}
*
* @exception JMSException if the JMS provider fails to get the correlation
* ID due to some internal error.
*
* @see javax.jms.Message#setJMSCorrelationID(String)
* @see javax.jms.Message#getJMSCorrelationIDAsBytes()
* @see javax.jms.Message#setJMSCorrelationIDAsBytes(byte[])
*/
String
getJMSCorrelationID() throws JMSException;
/** Gets the {@code Destination} object to which a reply to this
* message should be sent.
*
* @return {@code Destination} to which to send a response to this
* message
*
* @exception JMSException if the JMS provider fails to get the
* {@code JMSReplyTo} destination due to some
* internal error.
*
* @see javax.jms.Message#setJMSReplyTo(Destination)
*/
Destination
getJMSReplyTo() throws JMSException;
/** Sets the {@code Destination} object to which a reply to this
* message should be sent.
*
*
The {@code 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 a {@code Queue} object or
* a {@code Topic} object.
*
*
Messages sent with a null {@code 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 {@code 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
* {@code JMSCorrelationID} header field for this purpose.
*
* @param replyTo {@code Destination} to which to send a response to
* this message
*
* @exception JMSException if the JMS provider fails to set the
* {@code JMSReplyTo} destination due to some
* internal error.
*
* @see javax.jms.Message#getJMSReplyTo()
*/
void
setJMSReplyTo(Destination replyTo) throws JMSException;
/** Gets the {@code Destination} object for this message.
*
*
The {@code 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 {@code send} or {@code publish} method, the field
* holds the destination specified by the method.
*
*
When a message is received, its {@code JMSDestination} value
* must be equivalent to the value assigned when it was sent.
*
* @return the destination of this message
*
* @exception JMSException if the JMS provider fails to get the destination
* due to some internal error.
*
* @see javax.jms.Message#setJMSDestination(Destination)
*/
Destination
getJMSDestination() throws JMSException;
/** Sets the {@code Destination} 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.
*
* @param destination the destination for this message
*
* @exception JMSException if the JMS provider fails to set the destination
* due to some internal error.
*
* @see javax.jms.Message#getJMSDestination()
*/
void
setJMSDestination(Destination destination) throws JMSException;
/** Gets the {@code DeliveryMode} value specified for this message.
*
* @return the delivery mode for this message
*
* @exception JMSException if the JMS provider fails to get the
* delivery mode due to some internal error.
*
* @see javax.jms.Message#setJMSDeliveryMode(int)
* @see javax.jms.DeliveryMode
*/
int
getJMSDeliveryMode() throws JMSException;
/** Sets the {@code DeliveryMode} 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.
*
* @param deliveryMode the delivery mode for this message
*
* @exception JMSException if the JMS provider fails to set the
* delivery mode due to some internal error.
*
* @see javax.jms.Message#getJMSDeliveryMode()
* @see javax.jms.DeliveryMode
*/
void
setJMSDeliveryMode(int deliveryMode) throws JMSException;
/** Gets an indication of whether this message is being redelivered.
*
*
If a client receives a message with the {@code 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.
*
* @return true if this message is being redelivered
*
* @exception JMSException if the JMS provider fails to get the redelivered
* state due to some internal error.
*
* @see javax.jms.Message#setJMSRedelivered(boolean)
*/
boolean
getJMSRedelivered() throws JMSException;
/** 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.
*
* @param redelivered an indication of whether this message is being
* redelivered
*
* @exception JMSException if the JMS provider fails to set the redelivered
* state due to some internal error.
*
* @see javax.jms.Message#getJMSRedelivered()
*/
void
setJMSRedelivered(boolean redelivered) throws JMSException;
/** Gets the message type identifier supplied by the client when the
* message was sent.
*
* @return the message type
*
* @exception JMSException if the JMS provider fails to get the message
* type due to some internal error.
*
* @see javax.jms.Message#setJMSType(String)
*/
String
getJMSType() throws JMSException;
/** Sets the message type.
*
*
Some JMS providers use a message repository that contains the
* definitions of messages sent by applications. The {@code 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 {@code 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
* {@code 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.
*
* @param type the message type
*
* @exception JMSException if the JMS provider fails to set the message
* type due to some internal error.
*
* @see javax.jms.Message#getJMSType()
*/
void
setJMSType(String type) throws JMSException;
/** Gets the message's expiration time.
*
*
When a message is sent, the {@code JMSExpiration} header field
* is left unassigned. After completion of the {@code send} or
* {@code publish} 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, {@code 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.
*
* @return the message's expiration time value
*
* @exception JMSException if the JMS provider fails to get the message
* expiration due to some internal error.
*
* @see javax.jms.Message#setJMSExpiration(long)
*/
long
getJMSExpiration() throws JMSException;
/** 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.
*
* @param expiration the message's expiration time
*
* @exception JMSException if the JMS provider fails to set the message
* expiration due to some internal error.
*
* @see javax.jms.Message#getJMSExpiration()
*/
void
setJMSExpiration(long expiration) throws JMSException;
/**
* Gets the message's delivery time value.
*
*
* When a message is sent, the {@code JMSDeliveryTime} header field is
* left unassigned. After completion of the {@code send} or
* {@code publish} 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.
*
* @return the message's delivery time value
*
* @exception JMSException
* if the JMS provider fails to get the delivery time due to
* some internal error.
*
* @see javax.jms.Message#setJMSDeliveryTime(long)
*
* @since JMS 2.0
*/
long getJMSDeliveryTime() throws JMSException;
/**
* 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.
*
* @param deliveryTime
* the message's delivery time value
*
* @exception JMSException
* if the JMS provider fails to set the delivery time due to
* some internal error.
*
* @see javax.jms.Message#getJMSDeliveryTime()
*
* @since JMS 2.0
*/
void setJMSDeliveryTime(long deliveryTime) throws JMSException;
/** 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.
*
* @return the default message priority
*
* @exception JMSException if the JMS provider fails to get the message
* priority due to some internal error.
*
* @see javax.jms.Message#setJMSPriority(int)
*/
int
getJMSPriority() throws JMSException;
/** 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.
*
* @param priority the priority of this message
*
* @exception JMSException if the JMS provider fails to set the message
* priority due to some internal error.
*
* @see javax.jms.Message#getJMSPriority()
*/
void
setJMSPriority(int priority) throws JMSException;
/** Clears a message's properties.
*
*
The message's header fields and body are not cleared.
*
* @exception JMSException if the JMS provider fails to clear the message
* properties due to some internal error.
*/
void
clearProperties() throws JMSException;
/** Indicates whether a property value exists.
*
* @param name the name of the property to test
*
* @return true if the property exists
*
* @exception JMSException if the JMS provider fails to determine if the
* property exists due to some internal error.
*/
boolean
propertyExists(String name) throws JMSException;
/** Returns the value of the {@code boolean} property with the
* specified name.
*
* @param name the name of the {@code boolean} property
*
* @return the {@code boolean} property value for the specified name
*
* @exception JMSException if the JMS provider fails to get the property
* value due to some internal error.
* @exception MessageFormatException if this type conversion is invalid.
*/
boolean
getBooleanProperty(String name) throws JMSException;
/** Returns the value of the {@code byte} property with the specified
* name.
*
* @param name the name of the {@code byte} property
*
* @return the {@code byte} property value for the specified name
*
* @exception JMSException if the JMS provider fails to get the property
* value due to some internal error.
* @exception MessageFormatException if this type conversion is invalid.
*/
byte
getByteProperty(String name) throws JMSException;
/** Returns the value of the {@code short} property with the specified
* name.
*
* @param name the name of the {@code short} property
*
* @return the {@code short} property value for the specified name
*
* @exception JMSException if the JMS provider fails to get the property
* value due to some internal error.
* @exception MessageFormatException if this type conversion is invalid.
*/
short
getShortProperty(String name) throws JMSException;
/** Returns the value of the {@code int} property with the specified
* name.
*
* @param name the name of the {@code int} property
*
* @return the {@code int} property value for the specified name
*
* @exception JMSException if the JMS provider fails to get the property
* value due to some internal error.
* @exception MessageFormatException if this type conversion is invalid.
*/
int
getIntProperty(String name) throws JMSException;
/** Returns the value of the {@code long} property with the specified
* name.
*
* @param name the name of the {@code long} property
*
* @return the {@code long} property value for the specified name
*
* @exception JMSException if the JMS provider fails to get the property
* value due to some internal error.
* @exception MessageFormatException if this type conversion is invalid.
*/
long
getLongProperty(String name) throws JMSException;
/** Returns the value of the {@code float} property with the specified
* name.
*
* @param name the name of the {@code float} property
*
* @return the {@code float} property value for the specified name
*
* @exception JMSException if the JMS provider fails to get the property
* value due to some internal error.
* @exception MessageFormatException if this type conversion is invalid.
*/
float
getFloatProperty(String name) throws JMSException;
/** Returns the value of the {@code double} property with the specified
* name.
*
* @param name the name of the {@code double} property
*
* @return the {@code double} property value for the specified name
*
* @exception JMSException if the JMS provider fails to get the property
* value due to some internal error.
* @exception MessageFormatException if this type conversion is invalid.
*/
double
getDoubleProperty(String name) throws JMSException;
/** Returns the value of the {@code String} property with the specified
* name.
*
* @param name the name of the {@code String} property
*
* @return the {@code String} property value for the specified name;
* if there is no property by this name, a null value is returned
*
* @exception JMSException if the JMS provider fails to get the property
* value due to some internal error.
* @exception MessageFormatException if this type conversion is invalid.
*/
String
getStringProperty(String name) throws JMSException;
/** 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
* primitive settypeProperty method.
*
* @param name the name of the Java object property
*
* @return the Java object property value with the specified name, in
* objectified format (for example, if the property was set as an
* {@code int}, an {@code Integer} is
* returned); if there is no property by this name, a null value
* is returned
*
* @exception JMSException if the JMS provider fails to get the property
* value due to some internal error.
*/
Object
getObjectProperty(String name) throws JMSException;
/** Returns an {@code Enumeration} of all the property names.
*
*
Note that JMS standard header fields are not considered
* properties and are not returned in this enumeration.
*
* @return an enumeration of all the names of property values
*
* @exception JMSException if the JMS provider fails to get the property
* names due to some internal error.
*/
Enumeration
getPropertyNames() throws JMSException;
/** Sets a {@code boolean} property value with the specified name into
* the message.
*
* @param name the name of the {@code boolean} property
* @param value the {@code boolean} property value to set
*
* @exception JMSException if the JMS provider fails to set the property
* due to some internal error.
* @exception IllegalArgumentException if the name is null or if the name is
* an empty string.
* @exception MessageNotWriteableException if properties are read-only
*/
void
setBooleanProperty(String name, boolean value)
throws JMSException;
/** Sets a {@code byte} property value with the specified name into
* the message.
*
* @param name the name of the {@code byte} property
* @param value the {@code byte} property value to set
*
* @exception JMSException if the JMS provider fails to set the property
* due to some internal error.
* @exception IllegalArgumentException if the name is null or if the name is
* an empty string.
* @exception MessageNotWriteableException if properties are read-only
*/
void
setByteProperty(String name, byte value)
throws JMSException;
/** Sets a {@code short} property value with the specified name into
* the message.
*
* @param name the name of the {@code short} property
* @param value the {@code short} property value to set
*
* @exception JMSException if the JMS provider fails to set the property
* due to some internal error.
* @exception IllegalArgumentException if the name is null or if the name is
* an empty string.
* @exception MessageNotWriteableException if properties are read-only
*/
void
setShortProperty(String name, short value)
throws JMSException;
/** Sets an {@code int} property value with the specified name into
* the message.
*
* @param name the name of the {@code int} property
* @param value the {@code int} property value to set
*
* @exception JMSException if the JMS provider fails to set the property
* due to some internal error.
* @exception IllegalArgumentException if the name is null or if the name is
* an empty string.
* @exception MessageNotWriteableException if properties are read-only
*/
void
setIntProperty(String name, int value)
throws JMSException;
/** Sets a {@code long} property value with the specified name into
* the message.
*
* @param name the name of the {@code long} property
* @param value the {@code long} property value to set
*
* @exception JMSException if the JMS provider fails to set the property
* due to some internal error.
* @exception IllegalArgumentException if the name is null or if the name is
* an empty string.
* @exception MessageNotWriteableException if properties are read-only
*/
void
setLongProperty(String name, long value)
throws JMSException;
/** Sets a {@code float} property value with the specified name into
* the message.
*
* @param name the name of the {@code float} property
* @param value the {@code float} property value to set
*
* @exception JMSException if the JMS provider fails to set the property
* due to some internal error.
* @exception IllegalArgumentException if the name is null or if the name is
* an empty string.
* @exception MessageNotWriteableException if properties are read-only
*/
void
setFloatProperty(String name, float value)
throws JMSException;
/** Sets a {@code double} property value with the specified name into
* the message.
*
* @param name the name of the {@code double} property
* @param value the {@code double} property value to set
*
* @exception JMSException if the JMS provider fails to set the property
* due to some internal error.
* @exception IllegalArgumentException if the name is null or if the name is
* an empty string.
* @exception MessageNotWriteableException if properties are read-only
*/
void
setDoubleProperty(String name, double value)
throws JMSException;
/** Sets a {@code String} property value with the specified name into
* the message.
*
* @param name the name of the {@code String} property
* @param value the {@code String} property value to set
*
* @exception JMSException if the JMS provider fails to set the property
* due to some internal error.
* @exception IllegalArgumentException if the name is null or if the name is
* an empty string.
* @exception MessageNotWriteableException if properties are read-only
*/
void
setStringProperty(String name, String value)
throws JMSException;
/** 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 ({@code Integer}, {@code Double},
* {@code Long} ...) and {@code String} objects.
*
* @param name the name of the Java object property
* @param value the Java object property value to set
*
* @exception JMSException if the JMS provider fails to set the property
* due to some internal error.
* @exception IllegalArgumentException if the name is null or if the name is
* an empty string.
* @exception MessageFormatException if the object is invalid
* @exception MessageNotWriteableException if properties are read-only
*/
void
setObjectProperty(String name, Object value)
throws JMSException;
/** Acknowledges all consumed messages of the session of this consumed
* message.
*
*
All consumed JMS messages support the {@code acknowledge}
* method for use when a client has specified that its JMS session's
* consumed messages are to be explicitly acknowledged. By invoking
* {@code acknowledge} on a consumed message, a client acknowledges
* all messages consumed by the session that the message was delivered to.
*
*
Calls to {@code 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.
*
* @exception JMSException if the JMS provider fails to acknowledge the
* messages due to some internal error.
* @exception IllegalStateException if this method is called on a closed
* session.
*
* @see javax.jms.Session#CLIENT_ACKNOWLEDGE
*/
void
acknowledge() throws JMSException;
/** 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.
*
* @exception JMSException if the JMS provider fails to clear the message
* body due to some internal error.
*/
void
clearBody() throws JMSException;
/**
* 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.
*
*
* @param c
* The type to which the message body will be assigned.
* If the message is a {@code TextMessage} then this parameter must
* be set to {@code String.class} or another type to which
* a {@code String} is assignable.
* If the message is a {@code ObjectMessage} then parameter must
* must be set to {@code java.io.Serializable.class} or
* another type to which the body is assignable.
* If the message is a {@code MapMessage} then this parameter must
* be set to {@code java.util.Map.class} (or {@code java.lang.Object.class}).
* If the message is a {@code BytesMessage} then this parameter must
* be set to {@code byte[].class} (or {@code java.lang.Object.class}). This method
* will reset the {@code BytesMessage} before and after use.
* If the message is a
* {@code TextMessage}, {@code ObjectMessage}, {@code MapMessage}
* or {@code BytesMessage} 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 a {@code Message} (but not one of its subtypes)
* then this parameter may be set to any type;
* the returned value will always be null.
*
* @return the message body
*
* @exception MessageFormatException
*
* - if the message is a {@code StreamMessage}
*
- if the message body cannot be assigned to
* the specified type
*
- if the message is an {@code ObjectMessage} and object
* deserialization fails.
*
*
* @exception JMSException
* if the JMS provider fails to get the message body due to
* some internal error.
*
* @since JMS 2.0
*/
T getBody(Class c) throws JMSException;
/**
* 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
* method {@code getBody} on the same message with the same type argument would not throw a
* MessageFormatException.
*
* If the message is a {@code StreamMessage} then false is always returned.
* If the message is a {@code ObjectMessage} and object deserialization
* fails then false is returned. If the message has no body then any type may be specified and true is
* returned.
*
* @param c
* The specified type
* If the message is a {@code TextMessage} then this method will
* only return true if this parameter is set to
* {@code String.class} or another type to which a {@code String}
* is assignable.
* If the message is a {@code ObjectMessage} then this
* method will only return true if this parameter is set to
* {@code java.io.Serializable.class} or another class to
* which the body is assignable.
* If the message is a {@code MapMessage} then this method
* will only return true if this parameter is set to
* {@code java.util.Map.class} (or {@code java.lang.Object.class}).
* If the message is a {@code BytesMessage} then this this
* method will only return true if this parameter is set to
* {@code byte[].class} (or {@code java.lang.Object.class}).
* If the message is a
* {@code TextMessage}, {@code ObjectMessage}, {@code MapMessage}
* or {@code BytesMessage} 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 a
* {@code Message} (but not one of its subtypes)
* then this method will return true
* irrespective of the value of this parameter.
*
* @return whether the message body is capable of being assigned to the
* specified type
*
* @exception JMSException
* if the JMS provider fails to return a value due to some
* internal error.
*/
boolean isBodyAssignableTo(Class c) throws JMSException;
}