org.apache.qpid.server.management.plugin.report

Class QueueReport<T>

java.lang.Object

org.apache.qpid.server.management.plugin.report.QueueReport<T>

Type Parameters:

T -

Direct Known Subclasses:

QueueBinaryReport, QueueTextReport

public abstract class QueueReport<T>
extends Object

The QueueReport class provides an extension point for installations to provide custom management reporting on queues through the REST API.

A custom QueueReport must extend either QueueTextReport or QueueBinaryReport. The report implementation must define a name which is unique amongst all installed reports. The report class must be present in the classpath of the broker, and a provider-configuration file named org.apache.qpid.server.management.plugin.report.QueueReport must be added in the resource directory META-INF/services directory with the binary name of the implementation (as described in ServiceLoader).

Running reports

The report can be run using the URL: http://<broker>/service/queuereport/<virtualhost name>/<queue name>/<report name>[?param1=x&param2=y...]

Report Parameters

Reports can take parameters from the query string of the HTTP request. For every parameter in the query string the system will look for a setter on the report object with either a String or String[] parameter. Thus if the query string contains foo=bar, then the system will look for a setter setFoo(String value) or setFoo(String[] value). If the same parameter occurs multiple times in the query string then only the array variant of the setter will be called.

Setters for the parameters are guaranteed to be called before the first message is added to the report.

NOTE: In order to comply with the requirements of the ServiceLoader api, all implementations of QueueReport MUST provide a public no-args constructor.

Method Summary

Methods

Modifier and Type	Method and Description
abstract void	addMessage(ReportableMessage reportableMessage) Called by the system to add a message to the report.
abstract String	getContentType() The value returned by getContentType() will be used to set the Content-Type HTTP header field
abstract String	getName() Gets the name of the report.
String	getQueueName() Get the name of the queue against which the report is being run.
abstract T	getReport() Called by the system to get the content of the report to retrun to the user.
String	getVirtualHostName() Get the name of the virtual host against which the report is being run.
abstract boolean	isComplete() Informs the system if the report is complete (i.e.

Methods inherited from class java.lang.Object

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

Method Detail

getName

public abstract String getName()

Gets the name of the report.

The name of the report must be unique amongst all installed implementations. The name of the report is examined by the Qpid immediately upon construction. The name should not change during the lifetime of the object (the value is only meaningful to the system at the time of initial construction) and all instances of the same concrete implementation should have the same name.

Returns:

the name of the report

getQueueName

public final String getQueueName()

Get the name of the queue against which the report is being run.

Returns:

the name of the queue

getVirtualHostName

public final String getVirtualHostName()

Get the name of the virtual host against which the report is being run.

Returns:

the name of the virtual host

getContentType

public abstract String getContentType()

The value returned by getContentType() will be used to set the Content-Type HTTP header field

Returns:

the value to use for the content-type HTTP header field

addMessage

public abstract void addMessage(ReportableMessage reportableMessage)

Called by the system to add a message to the report.

The method is called by the system for every message on the queue, or until isComplete() returns true.

Parameters:

reportableMessage - the message to add to the report

isComplete

public abstract boolean isComplete()

Informs the system if the report is complete (i.e. does not need to report on any more messages).

This method will be called by the system after each message is added to the report. If a report is only interested in some messages, and can determine that the addition of more messages will not vary the content of the report, then it can return true.

If this method always returns false, then all messages from the queue will be added to the report.

NOTE: Retrieving content or properties of the message may require it to be reloaded from disk, and so care should be taken by reports to only access properties/content of the message if it is going to be required for the report production.

Returns:

true if the report does not want to report on any more messages in the queue

getReport

public abstract T getReport()

Called by the system to get the content of the report to retrun to the user.

The system guarantees to only call this method once

Returns:

the report content.