dk.netarkivet.common.utils
Class JMXUtils

java.lang.Object
  dk.netarkivet.common.utils.JMXUtils

public class JMXUtils
extends java.lang.Object

Various JMX-related utility functions that have nowhere better to live.

Field Summary

static org.apache.commons.logging.Log

log The logger.

Constructor Summary

JMXUtils()

Method Summary

static java.lang.Object	executeCommand(javax.management.remote.JMXConnector connector, java.lang.String beanName, java.lang.String command, java.lang.String... arguments) Execute a single command, closing the connector afterwards.
static java.lang.Object	executeCommand(javax.management.MBeanServerConnection connection, java.lang.String beanName, java.lang.String command, java.lang.String... arguments) Execute a command on a bean.
static java.lang.Object	getAttribute(javax.management.remote.JMXConnector connector, java.lang.String beanName, java.lang.String attribute) Get the value of an attribute, closing the connector afterwards.
static java.lang.Object	getAttribute(java.lang.String beanName, java.lang.String attribute, javax.management.MBeanServerConnection connection) Get the value of an attribute from a bean.
static javax.management.ObjectName	getBeanName(java.lang.String beanName) Get a bean name from a string version.
static javax.management.remote.JMXConnector	getJMXConnector(java.lang.String hostName, int jmxPort, java.lang.String login, java.lang.String password) Get a JMXConnector to a given host and port, using login and password.
static int	getMaxTries() The maximum number of times we back off on getting an mbean or a job.
static javax.management.MBeanServerConnection	getMBeanServerConnection(javax.management.remote.JMXServiceURL url, java.util.Map<java.lang.String,java.lang.String[]> credentials) Connects to the given (url-specified) service point, sending the given credentials as login.
static javax.management.MBeanServerConnection	getMBeanServerConnection(java.lang.String server, int jmxPort, int rmiPort, java.lang.String userName, java.lang.String password) Returns a connection to a remote MbeanServer defined by the given arguments.
static javax.management.openmbean.CompositeData	getOneCompositeData(javax.management.openmbean.TabularData items) Get a single CompositeData object out of a TabularData structure.
static javax.management.remote.JMXServiceURL	getUrl(java.lang.String server, int jmxPort, int rmiPort) Constructs the same service URL that JConsole does on the basis of a server name, a JMX port number, and a RMI port number.
static java.util.Map<java.lang.String,java.lang.String[]>	packageCredentials(java.lang.String userName, java.lang.String password) Packages credentials as an environment for JMX connections.

Methods inherited from class java.lang.Object

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

Field Detail

log

public static final org.apache.commons.logging.Log log

The logger.

Constructor Detail

JMXUtils

public JMXUtils()

Method Detail

getMaxTries

public static int getMaxTries()

The maximum number of times we back off on getting an mbean or a job. The cumulative time trying is 2^(MAX_TRIES) milliseconds, thus the constant is defined as log_2(TIMEOUT), as set in settings.

Returns:

The number of tries

getUrl

public static javax.management.remote.JMXServiceURL getUrl(java.lang.String server,
                                                           int jmxPort,
                                                           int rmiPort)

Constructs the same service URL that JConsole does on the basis of a server name, a JMX port number, and a RMI port number. Example URL: service:jmx:rmi://0.0.0.0:9999/jndi/rmi://0.0.0.0:1099/JMXConnector where RMI port number = 9999, JMX port number = 1099 server = 0.0.0.0 aka localhost(?).

Parameters:

server - The server that should be connected to using the constructed URL.

jmxPort - The number of the JMX port that should be connected to using the constructed URL (may not be a negative number)

rmiPort - The number of the RMI port that should be connected to using the constructed URL, or -1 if the default RMI port should be used.

Returns:

the constructed URL.

getMBeanServerConnection

public static javax.management.MBeanServerConnection getMBeanServerConnection(java.lang.String server,
                                                                              int jmxPort,
                                                                              int rmiPort,
                                                                              java.lang.String userName,
                                                                              java.lang.String password)

Returns a connection to a remote MbeanServer defined by the given arguments.

Parameters:

server - the remote servername

jmxPort - the remote jmx-port

rmiPort - the remote rmi-port

userName - the username

password - the password

Returns:

a MBeanServerConnection to a remote MbeanServer defined by the given arguments.

getMBeanServerConnection

public static javax.management.MBeanServerConnection getMBeanServerConnection(javax.management.remote.JMXServiceURL url,
                                                                              java.util.Map<java.lang.String,java.lang.String[]> credentials)

Connects to the given (url-specified) service point, sending the given credentials as login.

Parameters:

url - The JMX service url of some JVM on some machine.

credentials - a map with (at least) one entry, mapping "jmx.remote.credentials" to a String array of length 2. Its first item should be the user name. Its second item should be the password.

Returns:

An MBeanServerConnection representing the connected session.

packageCredentials

public static java.util.Map<java.lang.String,java.lang.String[]> packageCredentials(java.lang.String userName,
                                                                                    java.lang.String password)

Packages credentials as an environment for JMX connections. This packaging has the same form that JConsole uses: a one-entry Map, the mapping of "jmx.remote.credentials" being an array containing the user name and the password.

Parameters:

userName - The user to login as

password - The password to use for that user

Returns:

the packaged credentials

executeCommand

public static java.lang.Object executeCommand(javax.management.MBeanServerConnection connection,
                                              java.lang.String beanName,
                                              java.lang.String command,
                                              java.lang.String... arguments)

Execute a command on a bean.

Parameters:

connection - Connection to the server holding the bean.

beanName - Name of the bean.

command - Command to execute.

arguments - Arguments to the command. Only string arguments are possible at the moment.

Returns:

The return value of the executed command.

getAttribute

public static java.lang.Object getAttribute(java.lang.String beanName,
                                            java.lang.String attribute,
                                            javax.management.MBeanServerConnection connection)

Get the value of an attribute from a bean.

Parameters:

beanName - Name of the bean to get an attribute for.

attribute - Name of the attribute to get.

connection - A connection to the JMX server for the bean.

Returns:

Value of the attribute.

getBeanName

public static javax.management.ObjectName getBeanName(java.lang.String beanName)

Get a bean name from a string version.

Parameters:

beanName - String representation of bean name

Returns:

Object representing that bean name.

getJMXConnector

public static javax.management.remote.JMXConnector getJMXConnector(java.lang.String hostName,
                                                                   int jmxPort,
                                                                   java.lang.String login,
                                                                   java.lang.String password)

Get a JMXConnector to a given host and port, using login and password.

Parameters:

hostName - The host to attempt to connect to.

jmxPort - The port on the host to connect to (a non-negative number).

login - The login name to authenticate as (typically "controlRole" or "monitorRole".

password - The password for JMX access.

Returns:

A JMX connector to the given host and port, using default RMI.

Throws:

IOFailure - if connecting to JMX fails.

getOneCompositeData

public static javax.management.openmbean.CompositeData getOneCompositeData(javax.management.openmbean.TabularData items)

Get a single CompositeData object out of a TabularData structure.

Parameters:

items - TabularData structure as returned from JMX calls.

Returns:

The one item in the items structure.

Throws:

ArgumentNotValid - if there is not exactly one item in items, or items is null.

executeCommand

public static java.lang.Object executeCommand(javax.management.remote.JMXConnector connector,
                                              java.lang.String beanName,
                                              java.lang.String command,
                                              java.lang.String... arguments)

Execute a single command, closing the connector afterwards. If you wish to hold on to the connector, call JMXUtils#executeCommand(MBeanServerConnection, String, String, String[])

Parameters:

connector - A one-shot connector object.

beanName - The name of the bean to execute a command on.

command - The command to execute.

arguments - The arguments to the command (all strings)

Returns:

Whatever the command returned.

getAttribute

public static java.lang.Object getAttribute(javax.management.remote.JMXConnector connector,
                                            java.lang.String beanName,
                                            java.lang.String attribute)

Get the value of an attribute, closing the connector afterwards. If you wish to hold on to the connector, call JMXUtils#executeCommand(MBeanServerConnection, String, String, String[])

Parameters:

connector - A one-shot connector object.

beanName - The name of the bean to get an attribute from.

attribute - The attribute to get.

Returns:

Whatever the command returned.