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java.lang.Object | +--com.ibm.jms.JMSMessage
The Message interface is the root interface of all JMS messages. It defines the JMS header and the acknowledge() method used for all messages. The header contains fields used for message routing and identification. The payload contains the application data being sent.
JMS Messages are composed of the following parts:
JMS defines five types of message body:
The JMSCorrelationID header field is used to link one message with another. It typically links a reply message with its requesting message.
A JMSCorrelationID can hold either a provider-specific message ID, an application-specific String, or a provider-specific byte[] value.
A Message 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 and filter messages on its behalf using application-specific criteria.
Property names must obey the rules for the selector identifier of a message.
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 then be both read from and written to.
A property value might duplicate a value in a message's body or it might not. Although JMS does not define a policy for what should or should not be made a property, JMS handles data in a message's body more efficiently than data in a message's properties. For best performance, applications should only use message properties 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 are supported. The unmarked cases throw a JMSException. The String to primitive conversions might throw a runtime exception if the primitives valueOf() method does not accept it as a valid String 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 and 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 property type to be decided 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 throws 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 accessor 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. The other property get methods throw a java.lang.NullPointerException if they are used to get a nonexistent property.
JMS 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 String[] ConnectionMetaData.getJMSXPropertyNames() method returns the names of the JMSX properties supported by a connection.
JMSX properties can be referenced in message selectors whether or not they are supported by a connection. They are treated like any other absent property.
JSMX properties `set by provider on send' are available to both the producer and the consumers of the message. JSMX properties `set by provider on receive' are only available to the consumers.
JMSXGroupID and JMSXGroupSeq are simply standard properties that clients can use if they want to group messages.
JMS reserves the `JMS_
If an application tries to set a message property with a name that commences JMS, but the name is not one of the names in the following list, WebSphere MQ JMS throws an exception:
Field Summary |
Fields inherited from interface javax.jms.Message |
DEFAULT_DELIVERY_MODE, DEFAULT_PRIORITY, DEFAULT_TIME_TO_LIVE |
Method Summary | |
void |
acknowledge()
Acknowledges this and all previous messages received. |
void |
clearProperties()
Clears a message's properties. |
boolean |
getBooleanProperty(java.lang.String name)
Gets the boolean property value with the given name. |
byte |
getByteProperty(java.lang.String name)
Gets the byte property value with the given name. |
double |
getDoubleProperty(java.lang.String name)
Gets the double property value with the given name. |
float |
getFloatProperty(java.lang.String name)
Gets the float property value with the given name. |
int |
getIntProperty(java.lang.String name)
Gets the integer property value with the given name. |
java.lang.String |
getJMSCorrelationID()
Gets the correlation ID for the message. |
byte[] |
getJMSCorrelationIDAsBytes()
Gets the correlation ID as an array of bytes for the message. |
int |
getJMSDeliveryMode()
Gets the delivery mode for this message. |
javax.jms.Destination |
getJMSDestination()
Gets the destination for this message. |
long |
getJMSExpiration()
Gets the message's expiration value. |
java.lang.String |
getJMSMessageID()
Gets the message ID. |
int |
getJMSPriority()
Gets the message priority. |
boolean |
getJMSRedelivered()
Gets an indication of whether this message is being redelivered. |
javax.jms.Destination |
getJMSReplyTo()
Gets the destination to which a reply to this message should be sent. |
long |
getJMSTimestamp()
Gets the message timestamp. |
java.lang.String |
getJMSType()
Gets the message type. |
long |
getLongProperty(java.lang.String name)
Gets the long property value with the given name. |
java.lang.Object |
getObjectProperty(java.lang.String name)
Gets the Java object property value with the given name. |
java.util.Enumeration |
getPropertyNames()
Gets an Enumeration of all the property names. |
short |
getShortProperty(java.lang.String name)
Gets the short property value with the given name. |
java.lang.String |
getStringProperty(java.lang.String name)
Gets the String property value with the given name. |
boolean |
propertyExists(java.lang.String name)
Indicates whether a named property exists in the message properties hashtable. |
void |
setBooleanProperty(java.lang.String name,
boolean value)
Sets a boolean property value with the given name in the message. |
void |
setByteProperty(java.lang.String name,
byte value)
Sets a byte property value with the given name in the message. |
void |
setDoubleProperty(java.lang.String name,
double value)
Sets a double property value with the given name in the message. |
void |
setFloatProperty(java.lang.String name,
float value)
Sets a float property value with the given name in the message. |
void |
setIntProperty(java.lang.String name,
int value)
Sets an integer property value with the given name in the message. |
void |
setJMSCorrelationID(java.lang.String correlationID)
Sets the correlation ID for the message. |
void |
setJMSCorrelationIDAsBytes(byte[] correlID)
Sets the correlation ID as an array of bytes for the message. |
void |
setJMSDeliveryMode(int deliveryMode)
Sets the delivery mode for this message. |
void |
setJMSDestination(javax.jms.Destination destination)
Sets the destination for this message. |
void |
setJMSExpiration(long expiration)
Sets the message's expiration value. |
void |
setJMSMessageID(java.lang.String id)
Sets the message ID. |
void |
setJMSPriority(int priority)
Sets the priority for this message. |
void |
setJMSRedelivered(boolean redelivered)
Sets a boolean to indicate whether this message is being redelivered. |
void |
setJMSReplyTo(javax.jms.Destination replyTo)
Sets the destination to which a reply to this message should be sent. |
void |
setJMSTimestamp(long timestamp)
Sets the message timestamp. |
void |
setJMSType(java.lang.String type)
Sets the message type. |
void |
setLongProperty(java.lang.String name,
long value)
Sets a long property value with the given name in the message. |
void |
setObjectProperty(java.lang.String name,
java.lang.Object value)
Sets a Java object property value with the given name into the message. |
void |
setShortProperty(java.lang.String name,
short value)
Sets a short property value with the given name in the message. |
void |
setStringProperty(java.lang.String name,
java.lang.String value)
Sets a String property value with the given name in the message. |
java.lang.String |
toString()
Gets a String containing a formatted version of the Message header. |
Methods inherited from class java.lang.Object |
equals, getClass, hashCode, notify, notifyAll, wait, wait, wait |
Method Detail |
public void acknowledge() throws javax.jms.JMSException
acknowledge
in interface javax.jms.Message
javax.jms.JMSException
- with the following reasons;
public void clearProperties() throws javax.jms.JMSException
clearProperties
in interface javax.jms.Message
javax.jms.JMSException
- if an internal error occurs.public boolean getBooleanProperty(java.lang.String name) throws javax.jms.JMSException
getBooleanProperty
in interface javax.jms.Message
name
- the name of the boolean property.
javax.jms.MessageFormatException
- if this type conversion is invalid.
javax.jms.JMSException
- with reasons
java.lang.NullPointerException
- if name is null.setBooleanProperty(java.lang.String, boolean)
public byte getByteProperty(java.lang.String name) throws javax.jms.JMSException
getByteProperty
in interface javax.jms.Message
name
- the name of the byte property.
javax.jms.MessageFormatException
- if this type conversion is not valid.
javax.jms.JMSException
- with reasons
java.lang.NullPointerException
- if name is null.public double getDoubleProperty(java.lang.String name) throws javax.jms.JMSException
getDoubleProperty
in interface javax.jms.Message
name
- the name of the double property.
javax.jms.MessageFormatException
- if this type conversion is not valid.
javax.jms.JMSException
- with reasons
java.lang.NullPointerException
- if name is null.public float getFloatProperty(java.lang.String name) throws javax.jms.JMSException
getFloatProperty
in interface javax.jms.Message
name
- the name of the float property.
javax.jms.MessageFormatException
- if this type conversion is not valid.
javax.jms.JMSException
- with reasons
java.lang.NullPointerException
- if name is null.public int getIntProperty(java.lang.String name) throws javax.jms.JMSException
getIntProperty
in interface javax.jms.Message
name
- the name of the integer property
javax.jms.MessageFormatException
- if this type conversion is not valid.
javax.jms.JMSException
- with reasons
java.lang.NullPointerException
- if name is null.public java.lang.String getJMSCorrelationID() throws javax.jms.JMSException
This method is used to return correlation ID values that are either provider-specific message IDs or application-specific Strings.
getJMSCorrelationID
in interface javax.jms.Message
javax.jms.JMSException
- with reason
MQJMS_E_NO_UTF8
setJMSCorrelationID(java.lang.String)
public byte[] getJMSCorrelationIDAsBytes() throws javax.jms.JMSException
The use of a byte[] value for JMSCorrelationID is not portable.
getJMSCorrelationIDAsBytes
in interface javax.jms.Message
javax.jms.JMSException
- if an internal error occurs.public int getJMSDeliveryMode() throws javax.jms.JMSException
getJMSDeliveryMode
in interface javax.jms.Message
javax.jms.JMSException
- if an internal error occurs.public javax.jms.Destination getJMSDestination() throws javax.jms.JMSException
The destination field contains the destination to which the message is being sent.
When a message is sent, this value is ignored. After completion of the send() method it holds the destination specified by the send().
When a message is received, its destination value must be equivalent to the value assigned when it was sent.
getJMSDestination
in interface javax.jms.Message
javax.jms.JMSException
- with reason
MQJMS_EXCEPTION_INVALID_DESTINATION
public long getJMSExpiration() throws javax.jms.JMSException
When a message is sent, expiration is left unassigned. After completion of the send method, it holds the expiration time of the message. This is the time-to-live value specified by the client added to the time (GMT) when the message was sent.
If the time-to-live is specified as zero, expiration is set to zero which indicates the message does not expire.
When a message's expiration time is reached, a provider should discard it. JMS does not define any form of notification of message expiration.
Clients should not receive messages that have expired, although JMS does not guarantee that this will not happen.
getJMSExpiration
in interface javax.jms.Message
javax.jms.JMSException
- if an internal error occurs.public java.lang.String getJMSMessageID() throws javax.jms.JMSException
The messageID header field contains a value that uniquely identifies each message sent by a provider.
When a message is sent, messageID can be ignored. When the send() method returns, it contains a provider-assigned value.
A JMSMessageID is a String value which functions 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.
getJMSMessageID
in interface javax.jms.Message
javax.jms.JMSException
- if an internal error occurs.public int getJMSPriority() throws javax.jms.JMSException
JMS defines ten levels of priority with 0 as the lowest 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.
getJMSPriority
in interface javax.jms.Message
javax.jms.JMSException
- if an internal error occurs.public boolean getJMSRedelivered() throws javax.jms.JMSException
If a client receives a message with the redelivered indicator set, it is likely, but not guaranteed, that this message was delivered to the client earlier but the client did not acknowledge its receipt at that earlier time.
getJMSRedelivered
in interface javax.jms.Message
javax.jms.JMSException
- if an internal error occurs.public javax.jms.Destination getJMSReplyTo() throws javax.jms.JMSException
getJMSReplyTo
in interface javax.jms.Message
javax.jms.JMSException
- with reason
MQJMS_EXCEPTION_INVALID_DESTINATION
public long getJMSTimestamp() throws javax.jms.JMSException
The JMSTimestamp header field contains the time a message was handed to a provider to be sent. It is not the time the message was actually transmitted because that might occur later due to transactions or other client-side queueing of messages.
When a message is sent, JMSTimestamp is ignored. When the send method returns, it contains a time somewhere between the call and the return. It is in the format of a normal Java millisecond time value.
getJMSTimestamp
in interface javax.jms.Message
javax.jms.JMSException
- if an internal error occurs.public java.lang.String getJMSType() throws javax.jms.JMSException
getJMSType
in interface javax.jms.Message
javax.jms.JMSException
- if an internal error occurs.public long getLongProperty(java.lang.String name) throws javax.jms.JMSException
getLongProperty
in interface javax.jms.Message
name
- the name of the long property
javax.jms.JMSException
- with reasons
java.lang.NullPointerException
- if name is nullpublic java.lang.Object getObjectProperty(java.lang.String name) throws javax.jms.JMSException
This method can be used to return, in objectified format, an object that had been stored as a property in the Message with the equivalent setObject() method call, or its equivalent primitive setter method.
getObjectProperty
in interface javax.jms.Message
name
- the name of the Java object property.
int
, then an Integer is
returned). If there is no property with this name, a null value
is returned.
javax.jms.JMSException
- with reasons
java.lang.NullPointerException
- if name is nullsetObjectProperty(java.lang.String, java.lang.Object)
public java.util.Enumeration getPropertyNames() throws javax.jms.JMSException
getPropertyNames
in interface javax.jms.Message
javax.jms.JMSException
- if an internal error occurspublic short getShortProperty(java.lang.String name) throws javax.jms.JMSException
getShortProperty
in interface javax.jms.Message
name
- the name of the short property.
javax.jms.JMSException
- with reasons
public java.lang.String getStringProperty(java.lang.String name) throws javax.jms.JMSException
getStringProperty
in interface javax.jms.Message
name
- the name of the String property to retrieve.
javax.jms.JMSException
- with reason
public boolean propertyExists(java.lang.String name) throws javax.jms.JMSException
propertyExists
in interface javax.jms.Message
name
- the name of the property to test.
javax.jms.JMSException
- with reason
MQJMS_EXCEPTION_NULL_PROPERTY_NAME
.public void setBooleanProperty(java.lang.String name, boolean value) throws javax.jms.JMSException
setBooleanProperty
in interface javax.jms.Message
name
- the name of the boolean property.value
- the boolean
property value to set in the Message.
javax.jms.MessageNotWriteableException
- if properties are marked read-only
javax.jms.JMSException
- with reasons
public void setByteProperty(java.lang.String name, byte value) throws javax.jms.JMSException
setByteProperty
in interface javax.jms.Message
name
- the name of the byte property.value
- the byte
property value to set in the Message.
javax.jms.MessageNotWriteableException
- if properties are marked read-only
javax.jms.JMSException
- with reasons
public void setDoubleProperty(java.lang.String name, double value) throws javax.jms.JMSException
setDoubleProperty
in interface javax.jms.Message
name
- the name of the double propertyvalue
- the double
property value to set in the Message.
javax.jms.MessageNotWriteableException
- if properties are marked read-only
javax.jms.JMSException
- with reasons
public void setFloatProperty(java.lang.String name, float value) throws javax.jms.JMSException
setFloatProperty
in interface javax.jms.Message
name
- the name of the float property.value
- the float
property value to set in the Message.
javax.jms.MessageNotWriteableException
- if properties are marked read-only
javax.jms.JMSException
- with reasons
public void setIntProperty(java.lang.String name, int value) throws javax.jms.JMSException
setIntProperty
in interface javax.jms.Message
name
- the name of the integer property.value
- the integer property value to set in the Message.
javax.jms.MessageNotWriteableException
- if properties are marked read-only
javax.jms.JMSException
- with reasons
public void setJMSCorrelationID(java.lang.String correlationID) throws javax.jms.JMSException
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:
Since each message sent by a JMS provider is assigned a message ID, it is convenient to link messages using their message IDs. 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 example, an application might 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 might need to assign specific JMSCorrelationID values to match those expected by non-JMS clients. A byte[] value is used for this purpose. The use of a byte[] value for JMSCorrelationID is not portable.
setJMSCorrelationID
in interface javax.jms.Message
correlationID
- the message ID of a message being referred to.
javax.jms.JMSException
- with reasons
public void setJMSCorrelationIDAsBytes(byte[] correlID) throws javax.jms.JMSException
If a provider supports the native concept of correlation id, a JMS client might need to assign specific JMSCorrelationID values to match those expected by non-JMS clients.
A client can use this call to set the correlationID either to a messageID from a previous message, or to an application-specific string. Application-specific strings must not start with the characters 'ID:'.
The use of a byte[] value for JMSCorrelationID is not portable.
setJMSCorrelationIDAsBytes
in interface javax.jms.Message
correlID
- the correlation ID value as an array of bytes.
javax.jms.JMSException
- if an internal error occurs
java.lang.IndexOutOfBoundsException
- if copying would cause access to data outside array bounds.
java.lang.ArrayStoreException
- if an element in the source array could not be stored into the destination
array because of a type mismatch.
java.lang.NullPointerException
- if either source or destination is null.public void setJMSDeliveryMode(int deliveryMode) throws javax.jms.JMSException
Any value set using this method is ignored when the message is sent, but this method can be used to change the value in a received message.
To alter the delivery mode when a message is sent, use the setDeliveryMode() method on the QueueSender or TopicPublisher (this method is inherited from MessageProducer).
setJMSDeliveryMode
in interface javax.jms.Message
deliveryMode
- the delivery mode for this message.
javax.jms.JMSException
- if an internal error occurs.MQMessageProducer.setDeliveryMode(int)
public void setJMSDestination(javax.jms.Destination destination) throws javax.jms.JMSException
Any value set using this method is ignored when the message is sent, but this method can be used to change the value in a received message.
setJMSDestination
in interface javax.jms.Message
destination
- the destination for this message.
javax.jms.JMSException
- if an internal error occurs.public void setJMSExpiration(long expiration) throws javax.jms.JMSException
Any value set using this method is ignored when the message is sent, but this method can be used to change the value in a received message.
setJMSExpiration
in interface javax.jms.Message
expiration
- the message's expiration time.
javax.jms.JMSException
- if an internal error occurs.getJMSExpiration()
public void setJMSMessageID(java.lang.String id) throws javax.jms.JMSException
Any value set using this method is ignored when the message is sent, but this method can be used to change the value in a received message.
Because a message ID set by this method is ignored when a message is sent, an application cannot specify the message ID of an outgoing message. As a consequence, an application cannot receive a message and then forward the same message, or send a different message, with the same message ID as that of the message it has received. The behavior of WebSphere MQ classes for Java differs in this respect. An application using WebSphere MQ classes for Java can specify the message ID of an outgoing message.
setJMSMessageID
in interface javax.jms.Message
id
- the ID of the message.
javax.jms.JMSException
- if an internal error occurs.getJMSMessageID()
public void setJMSPriority(int priority) throws javax.jms.JMSException
Providers set this field when a message is sent. This operation can be used to change the value of a message that has been received.
JMS defines a ten levels of priority with 0 as the lowest and 9 as the highest. In addition, clients must consider priorities 0-4 as gradations of normal priority, and priorities 5-9 as gradations of expedited priority.
setJMSPriority
in interface javax.jms.Message
priority
- the priority of this message
javax.jms.JMSException
- if an internal error occurs.public void setJMSRedelivered(boolean redelivered) throws javax.jms.JMSException
This field is set at the time the message is delivered. This operation can be used to change the value of a message that has been received.
setJMSRedelivered
in interface javax.jms.Message
redelivered
- an indication of whether this message is being
re-delivered.
javax.jms.JMSException
- if an internal error occurs.public void setJMSReplyTo(javax.jms.Destination replyTo) throws javax.jms.JMSException
The replyTo 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 can be either a Queue or a Topic.
Messages with a null replyTo value are called JMS datagrams. Datagrams might contain a notification of some change in the sender (i.e. they signal a sender event) or they might just contain some data the sender thinks is of interest.
Messages with a replyTo value are typically expecting a response. A response is optional: it is up to the client to decide. These messages are called JMS requests. A message sent in response to a request is called a reply.
In some cases a client might wish to match a request it sent earlier with a reply it has just received. This can be done using the JMSCorrelationID.
setJMSReplyTo
in interface javax.jms.Message
replyTo
- where to send a response to this message
javax.jms.JMSException
- if an internal error occurs.public void setJMSTimestamp(long timestamp) throws javax.jms.JMSException
Providers set this field when a message is sent. This operation can be used to change the value of a message that has been received.
setJMSTimestamp
in interface javax.jms.Message
timestamp
- the timestamp for this message.
javax.jms.JMSException
- if an internal error occurs.public void setJMSType(java.lang.String type) throws javax.jms.JMSException
The type header field contains the name of a message's definition. JMS clients should assign a value whether the application makes use of it or not. This insures that it is properly set for the provider to use it, if required.
setJMSType
in interface javax.jms.Message
type
- the class of message
javax.jms.JMSException
- with reason
MQJMS_EXCEPTION_BAD_VALUE
.getJMSType()
public void setLongProperty(java.lang.String name, long value) throws javax.jms.JMSException
setLongProperty
in interface javax.jms.Message
name
- the name of the long property.value
- the long property value to set in the Message.
javax.jms.MessageNotWriteableException
- if properties are marked read-only
javax.jms.JMSException
- with reason
MQJMS_E_BAD_PROPERTY_NAME
public void setObjectProperty(java.lang.String name, java.lang.Object value) throws javax.jms.JMSException
This method only works for the 'objectified' primitive object types (Integer, Double, Long ...) and for Strings.
setObjectProperty
in interface javax.jms.Message
name
- the name of the Java object property.value
- the Java object property value to set in the Message.
javax.jms.MessageNotWriteableException
- if properties are marked read-only
javax.jms.MessageFormatException
- if the class of the object is not Number or String
javax.jms.JMSException
- with reason
MQJMS_E_BAD_PROPERTY_NAME
public void setShortProperty(java.lang.String name, short value) throws javax.jms.JMSException
setShortProperty
in interface javax.jms.Message
name
- the name of the short propertyvalue
- the short property value to set in the Message.
javax.jms.MessageNotWriteableException
- if properties are marked read-only
javax.jms.JMSException
- with reason
MQJMS_E_BAD_PROPERTY_NAME
public void setStringProperty(java.lang.String name, java.lang.String value) throws javax.jms.JMSException
setStringProperty
in interface javax.jms.Message
name
- the name of the String property.value
- the String property value to set in the Message.
javax.jms.MessageNotWriteableException
- if properties are marked read-only
javax.jms.JMSException
- with reason
MQJMS_E_BAD_PROPERTY_NAME
public java.lang.String toString()
toString
in class java.lang.Object
|
(c) Copyright IBM Corp. 2005. All Rights Reserved. | |||||||||
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