7
Advanced Queuing -- Java API

This chapter introduces and details the Java Application Programmer's Interface for Advanced Queuing under the following headings:

Introduction

The Java AQ API supports both the administrative and operational features of Oracle AQ. In developing Java programs for messaging applications, you will use JDBC to open a connection to the database and then the Java AQ API for message queuing. This means that you will no longer be required to use the PL/SQL interfaces.

The following sections describe the common interfaces and classes based on the current PL/SQL interfaces. The common interfaces are prefixed with "AQ". These interfaces will have different implementations in Oracle8i and Oracle Lite. In this document we describe the common interfaces and their corresponding Oracle8i implementations, which are in turn prefixed with "AQOracle".

The java AQ classes are located in $ORACLE_HOME/rdbms/jlib/aqapi.jar. These classes can be used with any Oracle8i JDBC driver. If your application uses the OCI8 or thin JDBC driver, you must include $ORACLE_HOME/rdbms/jlib/aqapi.jar in the CLASSPATH. If the application is using the KPRB driver and accessing the java AQ API from java stored procedures, you must first load the aqapi.jar file into the database using the "loadjava" utility.

Chapter 8, "Oracle Advanced Queuing by Example" contains the following examples:

Set up for the test_aqjava class is described in "Setup for AQ Examples".

The way to create a multi-consumer queue is described in the "AQSession".

AQDriverManager

The various implementations of the Java AQ API are managed via an AQDriverManager. Both OLite and Oracle8i will have an AQDriver which is registered with the AQDriverManager. The driver manager is used to create an AQSession which can be used to perform messaging tasks.

When the AQDriverManager.createAQSession() method is invoked, it calls the appropriate AQDriver (amongst the registered drivers) depending on the parameter passed to the createAQSession() call.

The Oracle8i AQDriver expects a valid JDBC connection to be passed in as a parameter to create an AQSession. Users must have the execute privilege on the DBMS_AQIN package in order to use the AQ Java interfaces. Users can also acquire these rights through the AQ_USER_ROLE or the AQ_ADMINSTRATOR_ROLE.Users will also need the appropriate system and queue privileges for 8.1 style queue tables.

Note:
Currently the Oracle8i AQDriver supports only RAW type payloads.

getDrivers

Purpose:

This method returns the list of drivers registered with the driver manager. It returns a Vector of strings containing the names of the registered drivers.

Syntax:

public static java.util.Vector getDrivers()

getAQSession

Purpose:

This method creates an AQSession.

Syntax:

public static AQSession getAQSession (java.lang.Object conn) throws AQException

Table 7-1 getAQSession Parameters

Parameter	Meaning
`conn`	if the user is using the `AQOracleDriver` , then the object passed in must be a valid JDBC connection

Multithreaded Program Support

Currently Java AQ objects are not thread safe. Therefore, methods on AQSession, AQQueueTable, AQQueue and other AQ objects should not be called concurrently from different threads. You can pass these objects between threads, but the program must ensure that the methods on these AQ objects are not invoked concurrently.

We recommend that multithreaded programs create a different AQSession in each thread (using the same or a different JDBC connection) and get new queue table and queue handles using the getQueueTable and getQueue methods in AQSession.

registerDriver

Purpose:

This method is used by various implementations of the AQ driver to register themselves with the driver manager (this method is not directly called by client programs)

Syntax:

public static void registerDriver(AQDriver aq_driver)

Note:
To create an AQSession, you must first open a JDBC connection. Then you must load the AQDriver that you need to use in the application. Note that the driver needs to be loaded only once (before the first createAQSession call). Loading the driver multiple times will have no effect. For more information, see "Setup for AQ Examples".

Example

Connection db_conn;       /* JDBC connection */
AQSession   aq_sess;       /* AQSession */

/* JDBC setup and connection creation: */
class.forName("oracle.jdbc.driver.OracleDriver");
db_conn = DriverManager.getConnection (
   "jdbc:oracle:oci8:@", "aquser", "aquser");
db_conn.setAutoCommit(false);

/* Load the Oracle8i AQ driver: */
class.forName("oracle.AQ.AQOracleDriver");
/* Create an AQ Session: */
aq_sess = AQDriverManager.createAQSession(db_conn);

APIs/Classes

Table 7-2 AQ Interfaces

Interface Summary	Description
AQSession	Open a session to the queuing system
AQQueueTable	AQ Queue Table interface
AQQueueAdmin	AQ Queue administrative interfaces
AQQueue	AQ Queue operational interfaces
AQMessage	AQ message
AQRaw Payload	AQ Raw Payload
AQDriver	Interface for various AQ drivers

Table 7-3 AQ Common Classes

Class Summary	Description
AQConstants	Constants used in AQ operations
AQAgent	AQ Agent
AQDriverManager	Driver Manager for various AQ drivers
AQEnqueueOption	AQ Enqueue Options
AQDequeueOption	AQ Dequeue options
AQMessageProperty	AQ Message properties
AQQueueProperty	AQ Queue properties
AQQueueTableProperty	AQ Queue Table properties

Table 7-4 Oracle8i AQ Classes

Class Summary	Description
AQOracleSession	Oracle server implementation of AQSession
AQOracleMessage	Oracle Server implementation of AQMessage
AQOracleDriver	Oracle server implementation of AQDriver
AQOracleQueue	Oracle server implementation of AQQueue
AQOracleQueueTable	Oracle server implementation of AQQueueTable
AQOracleRawPayload	Oracle server implementation of AQRawPayload

In general use only the interfaces and classes that are common to both implementations (as described in the first two tables). This will ensure that your applications are portable between Oracle 8i and Olite AQ implementations.

The AQOracle classes should not be used unless there is a method in these classes that is not available in the common interfaces.

Note that since the AQQueue interface extends AQQueueAdmin, all queue administrative and operation functionality is available via AQQueue.

AQSession

createQueueTable

Purpose:

This method creates a new queue table in a particular user's schema according to the properties specified in the AQQueueTableProperty object passed in.

Syntax:

public AQQueueTable createQueueTable(java.lang.String owner,
                                     java.lang.String name, 
                                     AQQueueTableProperty property) 
                                     throws AQException

Table 7-5 createQueueTable Parameters

Parameter	Meaning
`owner`	schema (user) in which to create the queue table
`q_name`	name of the queue table
`property`	queue table properties

Returns:

AQQueueTable object

getQueueTable

Purpose:

This method is used to get a handle to an existing queue table.

Syntax:

public AQQueueTable getQueueTable(java.lang.String owner, 
                                  java.lang.String name)

Table 7-6 getQueueTable Parameters

Parameter	Meaning
`owner`	schema (user) in which the queue table resides
`name`	name of the queue table

Returns:

AQQueueTable object

createQueue

Purpose:

This method creates a queue in a queue_table with the specified queue properties. It uses the same schema name that was used to create the queue table.

Syntax:

public AQQueue createQueue(AQQueueTable q_table,
                           java.lang.String q_name,
                           AQQueueProperty q_property) throws AQException

Table 7-7 createQueue Parameters

Parameter	Meaning
`q_table`	queue table in which to create queue
`name`	name of the queue to be created
`q_property`	queue properties

Returns:

AQQueue object

getQueue

Purpose:

This method can be used to get a handle to an existing queue.

Syntax:

public AQQueue getQueue(java.lang.String owner,
                        java.lang.String name)

Table 7-8 getQueue Parameters

Parameter	Meaning
`owner`	schema (user) in which the queue table resides
`name`	name of the queue

Returns:

AQQueue object

Usage Note

Currently the java AQ API supports only queues with raw payloads. If you try to access queue tables that contain queues with object payloads you will get an AQException with the message "payload type not supported."

Setup for AQ Examples

1. Create an AQ User

Here an 'aqjava' user is setup as follows:

CONNECT sys/change_on_install AS sysdba

DROP USER aqjava CASCADE;
GRANT CONNECT, RESOURCE, AQ_ADMINISTRATOR_ROLE TO aqjava IDENTIFIED BY aqjava;
GRANT EXECUTE ON SYS.DBMS_AQADM TO aqjava;
GRANT EXECUTE ON SYS.DBMS_AQ TO aqjava;
CONNECT aqjava/aqjava

2. Set up main class

Next we set up the main class from which we will call subsequent examples and handle exceptions.

import java.sql.*;
import oracle.AQ.*;

public class test_aqjava
{
   public static void main(String args[]) 
   {
      AQSession  aq_sess = null;

      try 
      {
         aq_sess = createSession(args);

        /* now run the test: */
        runTest(aq_sess);     
      }
      catch (Exception ex)
      {
         System.out.println("Exception-1: " + ex); 
         ex.printStackTrace();      
      }  
   }
}

3. Create an AQ Session;

Next,  an AQ Session is created for the 'aqjava' user as shown in the 
AQDriverManager section above:
 public static AQSession createSession(String args[]) 
   {
      Connection db_conn;
      AQSession  aq_sess = null;

      try 
      {
    
         Class.forName("oracle.jdbc.driver.OracleDriver");
         /* your actual hostname, port number, and SID will 
         vary from what follows. Here we use 'dlsun736,' '5521,'
         and 'test,' respectively: */

         db_conn =
                  DriverManager.getConnection(
                  "jdbc:oracle:thin:@dlsun736:5521:test", 
                  "aqjava", "aqjava");

         System.out.println("JDBC Connection opened "); 
         db_conn.setAutoCommit(false);
                 
         /* Load the Oracle8i AQ driver: */
         Class.forName("oracle.AQ.AQOracleDriver");

         /* Create an AQ Session: */
         aq_sess = AQDriverManager.createAQSession(db_conn);
         System.out.println("Successfully created AQSession ");  
      }
      catch (Exception ex)
      {
         System.out.println("Exception: " + ex); 
         ex.printStackTrace();      
      }  
      return aq_sess;
   }

Example

1. Create a queue table and a queue

Now, with the ' runTest' class, called from the above main class, we will create a queue table and queue for the 'aqjava' user.

public static void runTest(AQSession aq_sess) throws AQException
{
    AQQueueTableProperty     qtable_prop;
    AQQueueProperty          queue_prop;
    AQQueueTable             q_table;
    AQQueue                  queue;
   
    /* Create a AQQueueTableProperty object (payload type - RAW): */
    qtable_prop = new AQQueueTableProperty("RAW"); 
   
    /* Create a queue table called aq_table1 in aqjava schema: */
    q_table = aq_sess.createQueueTable ("aqjava", "aq_table1", qtable_prop);
    System.out.println("Successfully created aq_table1 in aqjava schema");  

    /* Create a new AQQueueProperty object: */
    queue_prop = new AQQueueProperty();
   
    /* Create a queue called aq_queue1 in aq_table1: */
    queue = aq_sess.createQueue (q_table, "aq_queue1", queue_prop);
    System.out.println("Successfully created aq_queue1 in aq_table1");  
}

2. Get a handle to an existing queue table and queue

public static void runTest(AQSession aq_sess) throws AQException
{
    AQQueueTable            q_table;
    AQQueue                 queue;
    
    /* Get a handle to queue table - aq_table1 in aqjava schema: */
    q_table = aq_sess.getQueueTable ("aqjava", "aq_table1");
    System.out.println("Successful getQueueTable");  
    
    /* Get a handle to a queue - aq_queue1 in aqjava schema: */
    queue = aq_sess.getQueue ("aqjava", "aq_queue1");
    System.out.println("Successful getQueue");  
}

AQConstants

This class contains some constants used in the java AQ API .

Visibility constants

VISIBILITY_IMMEDIATE
public static final int VISIBILITY_IMMEDIATE

VISIBILITY_ONCOMMIT
public static final int VISIBILITY_ONCOMMIT

Payload type

RAW_TYPE_PAYLOAD
public static final int RAW_TYPE_PAYLOAD

AQAgent

This object specifies the producer or a consumer of a message.

Constructor

Purpose:

There are two implementations of the constructor, each of which allocates a new AQAgent with the specified parameters.

Syntax:

public AQAgent(java.lang.String name,
               java.lang.String address,
               double protocol)

public AQAgent(java.lang.String name,
               java.lang.String address)

Table 7-9 AQAgent Parameters

Parameter	Meaning
`name`	agent name
`address`	agent address
`protocol`	agent protocol (required only in the first constructor); default is 0

getName

Purpose:

This method gets the agent name.

Syntax:

public java.lang.String getName() throws AQException

setName

Purpose:

This method sets the agent name.

Syntax:

public void setName(java.lang.String name) throws AQException

Table 7-10 setName Parameters

Parameter	Meaning
`name`	Agent name

getAddress

Purpose:

This method gets the agent address.

Syntax:

public java.lang.String getAddress() throws AQException

setAddress

Purpose:

This method sets the agent address.

Syntax:

public void setAddress(java.lang.String address) throws AQException

Table 7-11 setAddress Parameters

Parameter	Meaning
`address`	queue at a specific destination

getProtocol

Purpose:

This method gets the agent protocol.

Syntax:

public int getProtocol() throws AQException

setProtocol

Purpose:

This method sets the agent protocol.

Syntax:

public void setProtocol(int protocol) throws AQException

Table 7-12 setProtocol Parameters

Parameter	Meaning
`protocol`	Agent protocol

AQQueueTableProperty

This class represents queue table properties.

Constants for Message Grouping

public static final int NONE
public static final int TRANSACTIONAL

Constructor

Purpose:

This method creates an AQQueueTableProperty object with default property values and the specified payload type.

Syntax:

public AQQueueTableProperty(java.lang.String p_type)

Table 7-13 AQQueueTableProperty Parameters

Parameter	Meaning
`p_type`	payload type: this is "`RAW`" for queue tables that will contain raw payloads or the object type for queue tables that will contain structured payloads

Note:
Currently only payloads of RAW type are supported.

getPayloadType

Purpose:

This method returns "RAW" for raw payloads or the object type for object payloads.

Syntax:

public java.lang.String getPayloadType() throws AQException

setPayloadType

Purpose:

This method is used to set the payload type.

Syntax:

public void setPayloadType(java.lang.String p_type) throws AQException

Table 7-14 setPayloadType Parameters

Parameter	Meaning
`p_type`	payload type: this is "RAW" for queue tables that will contain raw payloads or the object type for queue tables that will contain structured payloads

setStorageClause

Purpose:

This method is used to set the storage clause to be used to create the queue table.

Syntax:

public void setStorageClause(java.lang.String s_clause) throws AQException

Table 7-15 setStorageClause Parameters

Parameter	Meaning
`s_clauses`	storage parameter: this clause is used in the ``CREATE TABLE`' statement when the queue table is created

getSortOrder

Purpose:

This method gets the sort order that is used.

Syntax:

public java.lang.String getSortOrder() throws AQException

Returns:

The sort order used

setSortOrder

Purpose:

This method sets the sort order to be used.

Syntax:

public void setSortOrder(java.lang.String s_order) throws AQException

Table 7-16 setSortOrder Parameters

Parameter	Meaning
`s_order`	specifies the columns to be used as the `sort_key` in ascending order; the string has the format <sort_column1, sort_column2>; the allowed columns name are `priority` and `enq_time.`

isMulticonsumerEnabled

Purpose:

This method queries whether the queues created in the table can have multiple consumers per message or not.

Syntax:

public boolean isMulticonsumerEnabled() throws AQException

Returns:

TRUE if the queues created in the table can have multiple consumers per message.

FALSE if the queues created in the table can have only one consumer per message.

setMultiConsumer

Purpose:

This method determines whether the queues created in the table can have multiple consumers per message or not.

Syntax:

public void setMultiConsumer(boolean enable) throws AQException

Table 7-17 setMultiConsumer Parameters

Parameter Meaning

Parameter	Meaning
`enable`	`FALSE` if the queues created in the table can have only one consumer per message `TRUE` if the queues created in the table can have multiple consumers per message

enable

FALSE if the queues created in the table can have only one consumer per message

TRUE if the queues created in the table can have multiple consumers per message

getMessageGrouping

Purpose:

This method is used to get the message grouping behavior for the queues in this queue table.

Syntax:

public int getMessageGrouping() throws AQException

Returns:

NONE: each message is treated individually

TRANSACTIONAL: all messages enqueued as part of one transaction are considered part of the same group and can be dequeued as a group of related messages.

setMessageGrouping

Purpose:

This method is used to set the message grouping behavior for queues created in this queue table.

Syntax:

public void setMessageGrouping(int m_grouping) throws AQException

Table 7-18 setMessageGrouping Parameters

Parameter	Meaning
`m_grouping`	`NONE` or `TRANSACTIONAL`

getComment

Purpose:

This method gets the queue table comment.

Syntax:

public java.lang.String getComment() throws AQException

setComment

Purpose:

This method sets a comment.

Syntax:

public void setComment(java.lang.String qt_comment) throws AQException

Table 7-19 setComment Parameters

Parameter	Meaning
`qt_comment`	comment

getCompatible

Purpose:

This method gets the compatible property.

Syntax:

public java.lang.String getCompatible() throws AQException

setCompatible

Purpose:

This method sets the compatible property.

Syntax:

public void setCompatible(java.lang.String qt_compatible) throws AQException

Table 7-20 setCompatible Parameters

Parameter	Meaning
`qt_compatible`	compatible property

getPrimaryInstance

Purpose:

This method gets the primary instance.

Syntax:

public int getPrimaryInstance() throws AQException

setPrimaryInstance

Purpose:

This method sets the primary instance.

Syntax:

public void setPrimaryInstance(int inst) throws AQException

Table 7-21 setPrimaryInstance Parameters

Parameter	Meaning
`inst`	primary instance

getSecondaryInstance

Purpose:

This method gets the secondary instance.

Syntax:

public int getSecondaryInstance() throws AQException

setSecondaryInstance

Purpose:

This method sets the secondary instance.

Syntax:

public void setSecondaryInstance(int inst) throws AQException

Table 7-22 setSecondaryInstance Parameters

Parameter	Meaning
`inst`	secondary instance

Examples:

Set up the test_aqjava class as described in "Setup for AQ Examples".

1. Create a queue table property object with raw payload type

public static void runTest(AQSession aq_sess) throws AQException
 {
     AQQueueTableProperty qtable_prop;

     /* Create AQQueueTable Property object: */
     qtable_prop = new AQQueueTableProperty("RAW");
     qtable_prop.setSortOrder("PRIORITY");
}

2. Create a queue table property object with raw payload type (for 8.1 style queues)

 public static void runTest(AQSession aq_sess) throws AQException
 {
     AQQueueTableProperty qtable_prop;

     /* Create AQQueueTable Property object: */
     qtable_prop = new AQQueueTableProperty("RAW");
     qtable_prop.setComment("Qtable with raw payload");
     qtable_prop.setCompatible("8.1");
}

AQQueueProperty

This class represents queue properties.

Constants:

public static final int NORMAL_QUEUE
public static final int EXCEPTION_QUEUE
public static final int INFINITE   /* infinite retention */

Constructor:

Purpose:

This method creates a new AQQueueProperty object with default property values.

Syntax:

public AQQueueProperty()

getQueueType

Purpose:

This method gets the queue type .

Syntax:

public int getQueueType() throws AQException

Returns:

NORMAL_QUEUE or EXCEPTION_QUEUE

setQueueType

Purpose:

This method is used to set the queue type.

Syntax:

public void setQueueType(int q_type) throws AQException

Table 7-23 setQueueType Parameters

Parameter	Meaning
`q_type`	`NORMAL_QUEUE` or `EXCEPTION_QUEUE`

getMaxRetries

Purpose:

This method gets the maximum retries for dequeue with REMOVE mode.

Syntax:

public int getMaxRetries() throws AQException

setMaxRetries

Purpose:

This method sets the maximum retries for dequeue with REMOVE mode.

Syntax:

public void setMaxRetries(int retries) throws AQException
public void setMaxRetries(Integer retries) throws AQException

Table 7-24 setMaxRetries Parameters

Parameter	Meaning
`retries`	maximum retries for dequeue with REMOVE mode; specifying `NULL` will use the default. The default applies to single consumer queues and 8.1. compatible multiconsumer queues. `Max_retries` is not supported for 8.0 compatible multiconsumer queues.

setRetryInterval

Purpose:

This method sets the retry interval, that is the time before this message is scheduled for processing after an application rollback. Default is 0.

Syntax:

public void setRetryInterval(double interval) throws AQException
public void setRetryInterval(Double interval) throws AQException

Table 7-25 setRetryInterval Parameters

Parameter	Meaning
`interval`	retry interval; specifying `NULL` will use the default

getRetryInterval

Purpose:

This method gets the retry interval.

Syntax:

public double getRetryInterval() throws AQException

getRetentionTime

Purpose:

This method gets the retention time.

Syntax:

public double getRetentionTime() throws AQException

setRetentionTime

Purpose:

This method gets the retention time.

Syntax:

public void setRetentionTime(double r_time) throws AQException
public void setRetentionTime(Double r_time) throws AQException

Table 7-26 setRetentionTime Parameters

Parameter	Meaning
`r_time`	retention time; specifying `NULL` will use the default

getComment

Purpose:

This method gets the queue comment.

Syntax:

public java.lang.String getComment() throws AQException

setComment

Purpose:

This method sets the queue comment.

Syntax:

public void setComment(java.lang.String qt_comment) throws AQException

Table 7-27 setComment Parameters

Parameter	Meaning
qt_comment	queue comment

Example:

Set up the test_aqjava class as described in Setup for AQ Examples.

Create a AQQueueProperty object

 {
     AQQueueProperty         q_prop;
     q_prop = new AQQueueProperty();
     q_prop.setRetentionTime(15); /* set retention time */
     q_prop.setRetryInterval(30); /* set retry interval  */
}

AQQueueTable

The AQQueueTable interface contains methods for queue table administration.

getOwner

Purpose:

This method gets the queue table owner.

Syntax:

public java.lang.String getOwner() throws AQException

getName

Purpose:

This method gets the queue table name.

Syntax:

public java.lang.String getName() throws AQException

getProperty

Purpose:

This method gets the queue table properties.

Syntax:

public AQQueueTableProperty getProperty() throws AQException

Returns:

AQQueueTableProperty object

drop

Purpose:

This method drops the current queue table.

Syntax:

public void drop(boolean force) throws AQException

Table 7-28 drop Parameters

Parameter Meaning

force

FALSE: this operation will not succeed if there are any queues in the queue table (the default)

TRUE : all queues in the queue table are stopped and dropped automatically

alter

Purpose:

This method is used to alter queue table properties.

Syntax:

public void alter(java.lang.String comment,
                  int primary_instance, 
                  int secondary_instance) throws AQException

public void alter(java.lang.String comment) throws AQException

Table 7-29 alter Parameters

Parameter	Meaning
`comment`	new comment
`primary_instance`	new value for primary instance
`secondary_instance`	new value for secondary instance

createQueue

Purpose:

This method is used to create a queue in this queue table.

Syntax:

public AQQueue createQueue(java.lang.String queue_name,
                           AQQueueProperty q_property) throws AQException

Table 7-30 createQueue Parameters

Parameter	Meaning
`queue_name`	name of the queue to be created
`q_property`	queue properties

Returns:

AQQueue object

dropQueue

Purpose:

This method is used to drop a queue in this queue table.

Syntax:

public void dropQueue(java.lang.String queue_name) throws AQException

Table 7-31 dropQueue Parameters

Parameter	Meaning
queue_name	name of the queue to be dropped

Example:

Set up the test_aqjava class as described in Setup for AQ Examples.

1. Create a queue table and a queue

public static void runTest(AQSession aq_sess) throws AQException
{
   AQQueueTableProperty    qtable_prop;
   AQQueueProperty         queue_prop;
   AQQueueTable            q_table;
   AQQueue                 queue;

   /* Create a AQQueueTable property object (payload type - RAW): */
   qtable_prop = new AQQueueTableProperty("RAW"); 
 
   /* Create a queue table called aq_table2 in aquser schema: */
   qtable = aq_sess.createQueueTable ("aquser", "aq_table2", qtable_prop);
   System.out.println("Successfully createQueueTable");  

   /* Create a new AQQueueProperty object: */
   queue_prop = new AQQueueProperty();

   /* Create a queue called aq_queue2 in aq_table2: */
   queue = qtable.createQueue ("aq_queue2", queue_prop);
   System.out.println("Successful createQueue");  
}

2. Alter queue table, get properties and drop the queue table

{
     AQQueueTableProperty    qtable_prop;
     AQQueueTable            q_table;
     
     /* Get a handle to the queue table called aq_table2 in aquser schema: */
     q_table = aq_sess.getQueueTable ("aqjava", "aq_table2");
     System.out.println("Successful getQueueTable");  

     /* Get queue table properties: */
     qtable_prop = q_table.getProperty();

     /* Alter the queue table: */
     q_table.alter("altered queue table");
     
     /* Drop the queue table (and automatically drop queues inside it): */
     q_table.drop(true);
     System.out.println("Successful drop"); 
}

Note:
Queues can be created via the AQSession.createQueue or the AQQueueTable.createQueue interfaces. The former expects an AQQueueTable object as a parameter in addition to the queue_name and queue properties.

AQQueueAdmin

start

Purpose:

This method is used to enable enqueue and dequeue on this queue.

Syntax:

public void start(boolean enqueue,
                  boolean dequeue) throws AQException

Table 7-32 start Parameters

Parameter Meaning

enqueue

TRUE -- enable enqueue on this queue

FALSE -- leave current setting unchanged

dequeue

TRUE -- enable dequeue on this queue

FALSE -- leave current setting unchanged

startEnqueue

Purpose:

This method is used to enable enqueue on this queue . This is equivalent to start(TRUE, FALSE)

Syntax:

public void startEnqueue() throws AQException

startDequeue

Purpose:

This method is used to enable dequeue on this queue. This is equivalent to start(FALSE, TRUE).

Syntax:

public void startDequeue() throws AQException

stop

Purpose:

This method is used to disable enqueue/dequeue on this queue.

Syntax:

public void stop(boolean enqueue,
                 boolean dequeue,
                 boolean wait) throws AQException

Table 7-33 stop Parameters

Parameter Meaning

enqueue

TRUE -- disable enqueue on this queue

FALSE -- leave current setting unchanged

dequeue

TRUE -- disable dequeue on this queue

FALSE -- leave current setting unchanged

wait

TRUE -- wait for outstanding transactions to complete

FALSE -- return immediately either with a success or an error

stopEnqueue

Purpose:

This method is used to disable enqueue on a queue. This is equivalent to stop(TRUE, FALSE, wait).

Syntax:

public void stopEnqueue(boolean wait) throws AQException

Table 7-34 stopEnqueue Parameters

Parameter Meaning

wait

TRUE -- wait for outstanding transactions to complete

FALSE -- return immediately either with a success or an error

stopDequeue

Purpose:

This method is used to disable dequeue on a queue. This is equivalent to stop(FALSE, TRUE, wait).

Syntax:

public void stopDequeue(boolean wait) throws AQException

Table 7-35 stopDequeue Parameters

Parameter Meaning

wait

TRUE -- wait for outstanding transactions to complete

FALSE -- return immediately either with a success or an error

drop

Purpose:

This method is used to drop a queue

Syntax:

public void drop() throws AQException

alterQueue

Purpose:

This method is used to alter queue properties

Syntax:

public void alterQueue(AQQueueProperty property) throws AQException

Table 7-36 alterQueue Parameters

Parameter	Meaning
`property`	`AQQueueProperty` object with new property values. Note that only `max_retries`, `retry_delay`, `retention_time` and `comment` can be altered.

addSubscriber

Purpose:

This method is used to add a subscriber for this queue.

Syntax:

public void addSubscriber(AQAgent subscriber,
                          java.lang.String rule) throws AQException

Table 7-37 addSubscriber Parameters

Parameter	Meaning
`subscriber`	the `AQAgent` on whose behalf the subscription is being defined
`rule`	a conditional expression based on message properties, and the message data properties

removeSubscriber

Purpose:

This method removes a subscriber from a queue.

Syntax:

public void removeSubscriber(AQAgent subscriber) throws AQException

Table 7-38 removeSubscriber Parameters

Parameter	Meaning
`subscriber`	the `AQAgent` to be removed

alterSubscriber

Purpose:

This method alters properties for a subscriber to a queue.

Syntax:

public void alterSubscriber(AQAgent subscriber,
                            java.lang.String rule) throws AQException

Table 7-39 alterSubscriber Parameters

Parameter	Meaning
`subscriber`	the `AQAgent` whose subscription is being altered
`rule`	a conditional expression based on message properties, the message data properties

grantQueuePrivilege

Purpose:

This method is used to grant queue privileges to users and roles. The method has been overloaded. The second implementation is equivalent to to calling the first imeplementation with grant_option = FALSE .

Syntax:

public void grantQueuePrivilege(java.lang.String privilege,
                                java.lang.String grantee, 
                                boolean grant_option) throws AQException

public void grantQueuePrivilege(java.lang.String privilege,
                                java.lang.String grantee) throws AQException

Table 7-40 grantQueuePrivilege Parameters

Parameter Meaning

privilege

specifies the privilege to be granted: ENQUEUE, DEQUEUE or ALL

grantee

specifies the grantee(s); the grantee(s) can be a user, a role or the PUBLIC roles

grant_option

TRUE -- the grantee is allowed to use this method to grant access to others

FALSE -- default

revokeQueuePrivilege

Purpose:

This method is used to revoke a queue privilege.

Syntax:

public void revokeQueuePrivilege(java.lang.String privilege,
                                 java.lang.String grantee) throws AQException

Table 7-41 revokeQueuePrivilege Parameters

Parameter	Meaning
`privilege`	specifies the privilege to be revoked`: ENQUEUE`, `DEQUEUE` or `ALL`
`grantee`	specifies the grantee(s); the grantee(s) can be a user, a role or the `PUBLIC` roles

schedulePropagation

Purpose:

This method is used to schedule propagation from a queue to a destination identified by a database link.

Syntax:

public void schedulePropagation(java.lang.String destination,
                                java.util.Date start_time,
                                java.lang.Double duration,
                                java.lang.String next_time,
                                java.lang.Double latency) throws AQException

Table 7-42 schedulePropagation Parameters

Parameter	Meaning
`destination`	specifies the destination database link. Messages in the source queue for recipients at the destination will be propagated. `NULL` => destination is the local database and messages will be propagated to all other queues in the local database. Maximum length for this field is 128 bytes. If the name is not fully qualified, the default domain name is used.
`start_time`	specifies the initial start time for the propagation window for messages from this queue to the destination. `NULL` => start time is current time.
`duration`	specifies the duration of the propagation window in seconds. `NULL` => propagation window is forever or until propagation is unscheduled
`next_time`	date function to compute the start of the next propagation window from the end of the current window. (e.g use "`SYSDATE`+ 1 - duration/86400" to start the window at the same time everyday. `NULL` => propagation will be stopped at the end of the current window
`latency`	maximum wait, in seconds, in the propagation window for the message to be propagated after it is enqueued. `NULL` => use default value (60 seconds)

unschedulePropagation

Purpose:

This method is used to unschedule a previously scheduled propagation of messages from the current queue to a destination identfied by a specific database link..

Syntax:

public void unschedulePropagation(java.lang.String destination) 
                                  throws AQException

Table 7-43 unschedulePropagation Parameters

Parameter	Meaning
destination	specifies the destination database link. `NULL` => destination is the local database.

alterPropagationSchedule

Purpose:

This method is used to alter a propagation schedule.

Syntax:

public void alterPropagationSchedule(java.lang.String destination,
                                     java.lang.Double duration,
                                     java.lang.String next_time,
                                     java.lang.Double latency)throws AQException

Table 7-44 alterPropagationSchedule Parameters

Parameter	Meaning
destination	specifies the destination database link. `NULL` => destination is the local database.
duration	specifies the duration of the propagation window in seconds. `NULL` => propagation window is forever or until propagation is unscheduled
next_time	date function to compute the start of the next propagation window from the end of the current window. (e.g use "`SYSDATE`+ 1 - duration/86400" to start the window at the same time everyday. `NULL` => propagation will be stopped at the end of the current window
latency	maximum wait, in seconds, in the propagation window for the message to be propagated after it is enqueued. `NULL` => use default value (60 seconds)

enablePropagationSchedule

Purpose:

This method is used to enable a propagation schedule.

Syntax:

public void enablePropagationSchedule(java.lang.String destination) 
                                      throws AQException

Table 7-45 enablePropagationSchedule Parameters

Parameter	Meaning
destination	specifies the destination database link. `NULL` => destination is the local database.

disablePropagationSchedule

Purpose:

This method is used to disable a propagation schedule.

Syntax:

public void disablePropagationSchedule(java.lang.String destination) 
                                       throws AQException

Table 7-46 disablePropagationSchedule Parameters

Parameter	Meaning
destination	specifies the destination database link. `NULL` => destination is the local database.

Examples:

Set up the test_aqjava class. For more information, see "Setup for AQ Examples"

1. Create a queue and start enqueue/dequeue

{
     AQQueueTableProperty    qtable_prop;
     AQQueueProperty         queue_prop;
     AQQueueTable            q_table;
     AQQueue                 queue;

     /* Create a AQQueueTable property object (payload type - RAW): */
     qtable_prop = new AQQueueTableProperty("RAW"); 
    qtable_prop.setCompatible("8.1");

     /* Create a queue table called aq_table3 in aqjava schema: */
     q_table = aq_sess.createQueueTable ("aqjava", "aq_table3", qtable_prop);
     System.out.println("Successful createQueueTable");  

     /* Create a new AQQueueProperty object: */
     queue_prop = new AQQueueProperty();

     /* Create a queue called aq_queue3 in aq_table3: */
     queue = aq_sess.createQueue (q_table, "aq_queue3", queue_prop);
     System.out.println("Successful createQueue");  

     /* Enable enqueue/dequeue on this queue: */
     queue.start();
     System.out.println("Successful start queue");  
   
     /* Grant enqueue_any privilege on this queue to user scott: */
     queue.grantQueuePrivilege("ENQUEUE", "scott"); 
     System.out.println("Successful grantQueuePrivilege");  
}

2. Create a multi-consumer queue and add subscribers

public static void runTest(AQSession aq_sess) throws AQException
{
     AQQueueTableProperty    qtable_prop;
     AQQueueProperty         queue_prop;
     AQQueueTable            q_table;
     AQQueue                 queue;
     AQAgent                  subs1, subs2;

     /* Create a AQQueueTable property object (payload type - RAW): */
     qtable_prop = new AQQueueTableProperty("RAW"); 
     System.out.println("Successful setCompatible");  

     /* Set multiconsumer flag to true: */
     qtable_prop.setMultiConsumer(true);

     /* Create a queue table called aq_table4 in aqjava schema: */
     q_table = aq_sess.createQueueTable ("aqjava", "aq_table4", qtable_prop);
     System.out.println("Successful createQueueTable");  

     /* Create a new AQQueueProperty object: */
     queue_prop = new AQQueueProperty();
     /* Create a queue called aq_queue4 in aq_table4 */
     queue = aq_sess.createQueue (q_table, "aq_queue4", queue_prop);
     System.out.println("Successful createQueue");  

     /* Enable enqueue/dequeue on this queue: */
     queue.start();
     System.out.println("Successful start queue");  

     /* Add subscribers to this queue: */
     subs1 = new AQAgent("GREEN", null, 0);
     subs2 = new AQAgent("BLUE", null, 0);

     queue.addSubscriber(subs1, null); /* no rule   */
     System.out.println("Successful addSubscriber 1");  

     queue.addSubscriber(subs2, "priority < 2"); /* with rule */
     System.out.println("Successful addSubscriber 2");  
}

AQQueue

This interface supports the operational interfaces of queues. AQQueue extends AQQueueAdmin. Hence, you can also use adminstrative functions through this interface.

getOwner

Purpose:

This method gets the queue owner.

Syntax:

public java.lang.String getOwner() throws AQException

getName

Purpose:

This method gets the queue name.

Syntax:

public java.lang.String getName() throws AQException

getQueueTableName

Purpose:

This method gets the name of the queue table in which the queue resides.

Syntax:

public java.lang.String getQueueTableName() throws AQException

getProperty

Purpose:

This method is used to get the queue properties.

Syntax:

public AQQueueProperty getProperty() throws AQException

Returns:

AQQueueProperty object

createMessage

Purpose:

This method is used to create a new AQMessage object that can be populated with data to be enqueued.

Syntax:

public AQMessage createMessage() throws AQException

Returns:

AQMessage object

enqueue

Purpose:

This method is used to enqueue a message in a queue.

Syntax:

public byte[] enqueue(AQEnqueueOption enq_option,
                      AQMessage message) throws AQException

Table 7-47 alterPropagationSchedule Parameters

Parameter	Meaning
`enq_option`	`AQEnqueOption` object
`message`	`AQMessage` to be enqueued

Returns:

Message id of the the enqueued message. The AQMessage object's messageId field is also populated after the completion of this call.

dequeue

Purpose:

This method is used to dequeue a message from a queue.

Syntax:

public AQMessage dequeue(AQDequeueOption deq_option) throws AQException

Table 7-48 alterPropagationSchedule Parameters

Parameter	Meaning
deq_option	`AQDequeueOption` object

Returns:

AQMessage,the dequeued message

getSubscribers

Purpose:

This method is used to get a subscriber list for the queue.

Syntax:

public AQAgent[] getSubscribers() throws AQException

Returns:

An array of AQAgents

AQEnqueueOption

This class is used to specify options available for the enqueue operation.

Constants

public static final int DEVIATION_NONE
public static final int DEVIATION_BEFORE
public static final int DEVIATION_TOP
public static final int VISIBILITY_ONCOMMIT
public static final int VISIBILITY_IMMEDIATE

Constructors

Purpose:

There are two constructors available. The first creates an object with the specified options, the second creates an object with the default options.

Syntax:

public AQEnqueueOption(int visibility,
                       byte[] relative_msgid,
                       int sequence_deviation)

public AQEnqueueOption()

Table 7-49 AQEnqueueOption Parameters

Parameter Meaning

visibility

VISIBILITY_IMMEDIATE or VISIBILITY_ONCOMMIT (default)

relative_msgid

when DEVIATION_BEFORE is used, this parameter identifies the message identifier of the message before which the current message is to be enqueued

sequence_deviation

DEVIATION_TOP-- the message is enqueued ahead of any other messages

DEVIATION_BEFORE -- the message is enqueued ahead of the message specified by relative_msgid

DEVIATION_NONE -- default

getVisibility

Purpose:

This method gets the visibility.

Syntax:

public int getVisibility() throws AQException

Returns:

VISIBILITY_IMMEDIATE or VISIBILITY_ONCOMMIT

setVisibility

Purpose:

This method sets the visibility.

Syntax:

public void setVisibility(int visibility) throws AQException

Table 7-50 setVisibility Parameters

Parameter	Meaning
`visibility`	`VISIBILITY_IMMEDIATE` or `VISIBILITY_ONCOMMIT`

getRelMessageId

Purpose:

This method gets the relative message id.

Syntax:

public byte[] getRelMessageId() throws AQException

getSequenceDeviation

Purpose:

This method gets the sequence deviation.

Syntax:

public int getSequenceDeviation() throws AQException

setSequenceDeviation

Purpose:

This method specfies whether the message being enqueued should be dequeued before other message(s) already in the queue

Syntax:

public void setSequenceDeviation(int sequence_deviation,
                                 byte[] relative_msgid) throws AQException

Table 7-51 setSequenceDeviation Parameters

Parameter Meaning

sequence_deviation

DEVIATION_TOP-- the message is enqueued ahead of any other messages

DEVIATION_BEFORE -- the message is enqueued ahead of the message specified by relative_msgid

DEVIATION_NONE -- default

relative_msgid

when DEVIATION_BEFORE is used, this parameter identifies the message identifier of the message before which the current message is to be enqueued

AQDequeueOption

This class is used to specify the options available for the dequeue option.

Constants

public static final int NAVIGATION_FIRST_MESSAGE
public static final int NAVIGATION_NEXT_TRANSACTION
public static final int NAVIGATION_NEXT_MESSAGE
public static final int DEQUEUE_BROWSE
public static final int DEQUEUE_LOCKED
public static final int DEQUEUE_REMOVE
public static final int DEQUEUE_REMOVE_NODATA
public static final int WAIT_FOREVER
public static final int WAIT_NONE
public static final int VISIBILITY_ONCOMMIT
public static final int VISIBILITY_IMMEDIATE

Constructor

Purpose:

This method creates an object with the default options.

Syntax:

public AQDequeueOption()

getConsumerName

Purpose:

This method gets consumer name.

Syntax:

public java.lang.String getConsumerName() throws AQException

setConsumerName

Purpose:

This method sets consumer name

Syntax:

public void setConsumerName(java.lang.String consumer_name) throws AQException

Table 7-52 setConsumerName Parameters

Parameter	Meaning
consumer_name	Agent name

getDequeueMode

Purpose:

This method gets dequeue mode

Syntax:

public int getDequeueMode() throws AQException

Returns:

DEQUEUE_BROWSE, DEQUEUE_LOCKED, DEQUEUE_REMOVE or DEQUEUE_REMOVE_NODATA

setDequeueMode

Purpose:

This method sets the dequeue mode.

Syntax:

public void setDequeueMode(int dequeue_mode) throws AQException

Table 7-53 setDequeueMode Parameters

Parameter	Meaning
dequeue_mode	`DEQUEUE_BROWSE`, `DEQUEUE_LOCKED`, `DEQUEUE_REMOVE` or `DEQUEUE_REMOVE_NODATA`

getNavigationMode

Purpose:

This method gets the navigation mode.

Syntax:

public int getNavigationMode() throws AQException

Returns:

NAVIGATION_FIRST_MESSAGE or NAVIGATION_NEXT_MESSAGE or NAVIGATION_NEXT_TRANSACTION

setNavigationMode

Purpose:

This method sets the navigation mode.

Syntax:

public void setNavigationMode(int navigation) throws AQException

Table 7-54 setNavigationMode Parameters

Parameter	Meaning
navigation	`NAVIGATION_FIRST_MESSAGE` or `NAVIGATION_NEXT_MESSAGE` or `NAVIGATION_NEXT_TRANSACTION`

getVisibility

Purpose:

This method gets the visibility.

Syntax:

public int getVisibility() throws AQException

Returns:

VISIBILITY_IMMEDIATE or VISIBILITY_ONCOMMIT

setVisibility

Purpose:

This method sets the visibility.

Syntax:

public void setVisibility(int visibility) throws AQException

Table 7-55 setVisibility Parameters

Parameter	Meaning
`visibility`	`VISIBILITY_IMMEDIATE` or `VISIBILITY_ONCOMMIT`

getWaitTime

Purpose:

This method gets the wait time.

Syntax:

public int getWaitTime() throws AQException

Returns:

WAIT_FOREVER or WAIT_NONE or the actual time in seconds

setWaitTime

Purpose:

This method sets the wait time.

Syntax:

public void setWaitTime(int wait_time) throws AQException

Table 7-56 setWaitTime Parameters

Parameter	Meaning
`wait_time`	`WAIT_FOREVER` or `WAIT_NONE` or time in seconds

getMessageId

Purpose:

This method gets the message id.

Syntax:

public byte[] getMessageId() throws AQException

setMessageId

Purpose:

This method sets the message id.

Syntax:

public void setMessageId(byte[] message_id) throws AQException

Table 7-57 setMessageId Parameters

Parameter	Meaning
`message_id`	message id

getCorrelation

Purpose:

This method gets the correlation id.

Syntax:

public java.lang.String getCorrelation() throws AQException

setCorrelation

Purpose:

This method sets the correlation id.

Syntax:

public void setCorrelation(java.lang.String correlation) throws AQException

Table 7-58 setCorrelation Parameters

Parameter	Meaning
`correlation`	user-supplied information

AQMessage

This interface contains methods for AQ messages with raw or object payloads.

getMessageId

Purpose:

This method gets the message id.

Syntax:

public byte[] getMessageId() throws AQException

getRawPayload

Purpose:

This method gets the raw payload

Syntax:

public AQRawPayload getRawPayload() throws AQException

Returns:

AQRawPayload object

setRawPayload

Purpose:

This method sets the raw payload. It throws AQException if this is called on messages created from object type queues.

Syntax:

public void setRawPayload(AQRawPayload message_payload) throws AQException

Table 7-59 setRawPayload Parameters

Parameter	Meaning
message_payload	`AQRawPayload` object containing raw user data

getMessageProperty

Purpose:

This method gets the message properties

Syntax:

public AQMessageProperty getMessageProperty() throws AQException

Returns:

AQMessageProperty object

setMessageProperty

Purpose:

This method sets the message properties.

Syntax:

public void setMessageProperty(AQMessageProperty property) throws AQException

Table 7-60 setObjectPayload Parameters

Parameter	Meaning
`property`	AQMessageProperty object

AQMessageProperty

The AQMessageProperty class contains information that is used by AQ to manage individual messages. The properties are set at enqueue time and their values are returned at dequeue time.

Constants

public static final int DELAY_NONE
public static final int EXPIRATION_NEVER
public static final int STATE_READY
public static final int STATE_WAITING
public static final int STATE_PROCESSED
public static final int STATE_EXPIRED

Constructor

Purpose:

This method creates the AQMessageProperty object with default property values.

Syntax:

public AQMessageProperty()

getPriority

Purpose:

This method gets the message priority.

Syntax:

public int getPriority() throws AQException

setPriority

Purpose:

This method sets the message priority.

Syntax:

public void setPriority(int priority) throws AQException

Table 7-61 setPriority Parameters

Parameter	Meaning
`priority`	priority of the message; this can be any number, including negative number - a smaller number indicates a higher priority

getDelay

Purpose:

This method gets the delay value.

Syntax:

public int getDelay() throws AQException

setDelay

Purpose:

This method sets delay value.

Syntax:

public void setDelay(int delay) throws AQException

Table 7-62 setDelay Parameters

Parameter	Meaning
`delay`	the delay represents the number of seconds after which the message is available for dequeuing; with `NO_DELAY` the message is available for immediate dequeuing

getExpiration

Purpose:

This method gets expiration value

Syntax:

public int getExpiration() throws AQException

setExpiration

Purpose:

This method sets expiration value

Syntax:

public void setExpiration(int expiration) throws AQException

Table 7-63 setExpiration Parameters

Parameter	Meaning
`expiration`	the duration the message is available for dequeuing; this parameter is an offset from the delay; if `NEVER`, the message will not expire

getCorrelation

Purpose:

This method gets correlation

Syntax:

public java.lang.String getCorrelation() throws AQException

setCorrelation

Purpose:

This method sets correlation

Syntax:

public void setCorrelation(java.lang.String correlation) throws AQException

Table 7-64 setCorrelation Parameters

Parameter	Meaning
`correlation`	user-supplied information

getAttempts

Purpose:

This method gets the number of attempts.

Syntax:

public int getAttempts() throws AQException

getRecipientList

Purpose:

This method gets the recipient list.

Syntax:

public java.util.Vector getRecipientList() throws AQException

Returns:

A vector of AQAgents.This parameter is not returned to a consumer at dequeue time.

setRecipientList

Purpose:

This method sets the recipient list.

Syntax:

public void setRecipientList(java.util.Vector r_list) throws AQException

Table 7-65 setRecipientList Parameters

Parameter	Meaning
`r_list`	vector of `AQAgents`; the default recipients are the queue subscribers

getOrigMessageId

Purpose:

This method gets original message id.

Syntax:

public byte[] getOrigMessageId() throws AQException

getSender

Purpose:

This method gets the sender of the message.

Syntax:

public AQAgent getSender() throws AQException

setSender

Purpose:

This method sets the sender of the message.

Syntax:

public void setSender(AQAgent sender) throws AQException

Table 7-66 setSender Parameters

Parameter	Meaning
sender	AQAgent

getExceptionQueue

Purpose:

This method gets the exception queue name.

Syntax:

public java.lang.String getExceptionQueue() throws AQException

setExceptionQueue

Purpose:

This method sets the exception queue name.

Syntax:

public void setExceptionQueue(java.lang.String queue) throws AQException

Table 7-67 setExceptionQueue Parameters

Parameter	Meaning
queue	exception queue name

getEnqueueTime

Purpose:

This method gets the enqueue time.

Syntax:

public java.util.Date getEnqueueTime() throws AQException

getState

Purpose:

This method gets the message state.

Syntax:

public int getState() throws AQException

Returns:

STATE_READY or STATE_WAITING or STATE_PROCESSED or STATE_EXPIRED

AQRawPayload

This object represents the raw user data that is included in AQMessage.

getStream

Purpose:

This method reads some portion of the raw payload data into the specified byte array.

Syntax:

public int getStream(byte[] value, int len) throws AQException

Table 7-68 getStream Parameters

Parameter	Meaning
`value`	byte array to hold the raw data
`len`	number of bytes to be read

Returns:

The number of bytes read

getBytes

Purpose:

This method retrieves the entire raw payload data as a byte array.

Syntax:

public byte[] getBytes() throws AQException

Returns:

byte[] - the raw payload as a byte array

setStream

Purpose:

This method sets the value of the raw payload.

Syntax:

public void setStream(byte[] value,
                      int len) throws AQException

Table 7-69 getStream Parameters

Parameter	Meaning
`value`	byte array containing the raw payload
`len`	number of bytes to be written to the raw stream

AQException

This exception is raised when the user encounters any error while using the Java AQ Api.

public class AQException extends java.lang.RuntimeException

This interface supports all methods supported by Java exceptions and some additional methods.

getMessage

Purpose:

This method gets the error message.

getErrorCode

Purpose:

This method gets the error number (Oracle error code).

getNextException

Purpose:

This method gets the next exception in the chain if any.

AQOracleSQLException

AQOracleSQLException extends AQException.

When using Oracle8i AQ driver, some errors may be raised from the client side and some from the RDBMS. The Oracle8i driver raises AQOracleSQLException for all errors that ocuur while performing SQL.

For sophisticated users interested in differentiating between the two types of exceptions, this interface might be useful. In general you will only use AQException.

7 Advanced Queuing -- Java API

Introduction

AQDriverManager

getDrivers

Purpose:

Syntax:

getAQSession

Purpose:

Syntax:

Table 7-1 getAQSession Parameters

Multithreaded Program Support

registerDriver

Purpose:

Syntax:

Example

APIs/Classes

Table 7-2 AQ Interfaces

Table 7-3 AQ Common Classes

Table 7-4 Oracle8i AQ Classes

AQSession

createQueueTable

Purpose:

Syntax:

Table 7-5 createQueueTable Parameters

Returns:

getQueueTable

Purpose:

Syntax:

Table 7-6 getQueueTable Parameters

Returns:

createQueue

Purpose:

Syntax:

Table 7-7 createQueue Parameters

Returns:

getQueue

Purpose:

Syntax:

Table 7-8 getQueue Parameters

Returns:

Usage Note

Setup for AQ Examples

1. Create an AQ User

2. Set up main class

3. Create an AQ Session;

Example

1. Create a queue table and a queue

2. Get a handle to an existing queue table and queue

AQConstants

Visibility constants

Payload type

AQAgent

Constructor

Purpose:

Syntax:

Table 7-9 AQAgent Parameters

getName

Purpose:

Syntax:

setName

Purpose:

Syntax:

Table 7-10 setName Parameters

getAddress

Purpose:

Syntax:

setAddress

Purpose:

Syntax:

Table 7-11 setAddress Parameters

getProtocol

Purpose:

Syntax:

setProtocol

Purpose:

Syntax:

Table 7-12 setProtocol Parameters

AQQueueTableProperty

Constants for Message Grouping

Constructor

7
Advanced Queuing -- Java API