alma.acs.commandcenter.engine

Class NativeCommand

java.lang.Object

alma.acs.commandcenter.engine.NativeCommand

All Implemented Interfaces:

java.lang.Runnable

public class NativeCommand
extends java.lang.Object
implements java.lang.Runnable

Describes and encapsulates a native command. A native command triggers a process, and provides various bells and whistles around the pure process object as provided by the Java Runtime. The native command can be run a) within its own thread (as it implements Runnable), or b) directly via a call to its run() method.

Author:

mschilli

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static interface	NativeCommand.Listener Interested in Processes? Be a NativeCommand Listener today!
static class	NativeCommand.ListenerAdapter An empty implementation of the Listener interface.
protected class	NativeCommand.Reader Reads a process's streams.
protected class	NativeCommand.Spawner Runs a process.
protected class	NativeCommand.Watcher Polls the process behavior and sends events to Listeners if something interesting happens.

Field Summary

Fields

Modifier and Type	Field and Description
static java.lang.String	CANNOTRUN
protected java.lang.String	command
static long	DEFAULT_WATCHER_DELAY
static long	DEFAULT_WATCHER_INTERVAL
protected long	delay
protected java.lang.String	endMark
protected java.lang.Integer	exitValue
protected boolean	foreground
protected long	interval
protected java.lang.Throwable	latestException
protected java.util.Vector<NativeCommand.Listener>	listeners
protected java.util.logging.Logger	log
protected long	maxExecutionTime
static java.lang.String	NEW
static long	NO_TIMEOUT
protected java.lang.Process	process
static java.lang.String	RUNNING
protected java.lang.String	status
protected java.io.OutputStreamWriter	stdin
static java.lang.String	TERMINATED
protected java.util.concurrent.ThreadFactory	threadFactory
protected java.util.concurrent.ThreadFactory	threadFactoryDefault The default thread factory for background actions.
static java.lang.String	TIMEOUT
protected static java.util.Timer	watchers

Constructor Summary

Constructors

Constructor and Description
NativeCommand(java.lang.String command, boolean foreground)
NativeCommand(java.lang.String command, boolean foreground, long maxExecutionTime)
NativeCommand(java.lang.String command, boolean foreground, long maxExecutionTime, java.lang.String endMark)
NativeCommand(java.lang.String command, boolean foreground, long maxExecutionTime, java.lang.String endMark, long interval, long delay)

Method Summary

Modifier and Type	Method and Description
void	addListener(NativeCommand.Listener po)
protected void	changeStatus(java.lang.String newStatus)
protected void	fireOutputWritten(java.io.InputStream sourceStream, java.lang.String additionalOutput)
protected void	fireStatusChanged(java.lang.String oldStatus, java.lang.String newStatus)
java.lang.Integer	getExitValue()
java.lang.Throwable	getLatestException() Returns the most recent occured error.
java.lang.String	getStatus()
void	removeListener(NativeCommand.Listener po)
void	run() We use four delegates: One to start a process One to watch its progress Two to read its output (out and err) The delegates give feedback to the main thread by provoking InterruptedExceptions on it.
void	send(java.lang.String text) Writes the given text to the STDIN of the process.
void	setThreadFactory(java.util.concurrent.ThreadFactory threads) This class executes various actions concurrently.

Methods inherited from class java.lang.Object

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

Field Detail

NEW

public static final java.lang.String NEW

See Also:

Constant Field Values

RUNNING

public static final java.lang.String RUNNING

See Also:

Constant Field Values

TERMINATED

public static final java.lang.String TERMINATED

See Also:

Constant Field Values

CANNOTRUN

public static final java.lang.String CANNOTRUN

See Also:

Constant Field Values

TIMEOUT

public static final java.lang.String TIMEOUT

See Also:

Constant Field Values

NO_TIMEOUT

public static final long NO_TIMEOUT

See Also:

Constant Field Values

DEFAULT_WATCHER_INTERVAL

public static long DEFAULT_WATCHER_INTERVAL

DEFAULT_WATCHER_DELAY

public static long DEFAULT_WATCHER_DELAY

watchers

protected static java.util.Timer watchers

stdin

protected java.io.OutputStreamWriter stdin

listeners

protected java.util.Vector<NativeCommand.Listener> listeners

command

protected java.lang.String command

process

protected java.lang.Process process

interval

protected long interval

delay

protected long delay

maxExecutionTime

protected long maxExecutionTime

status

protected java.lang.String status

foreground

protected boolean foreground

endMark

protected java.lang.String endMark

latestException

protected java.lang.Throwable latestException

exitValue

protected java.lang.Integer exitValue

log

protected java.util.logging.Logger log

threadFactoryDefault

protected java.util.concurrent.ThreadFactory threadFactoryDefault

The default thread factory for background actions.

threadFactory

protected java.util.concurrent.ThreadFactory threadFactory

Constructor Detail

NativeCommand

public NativeCommand(java.lang.String command,
                     boolean foreground)

NativeCommand

public NativeCommand(java.lang.String command,
                     boolean foreground,
                     long maxExecutionTime)

NativeCommand

public NativeCommand(java.lang.String command,
                     boolean foreground,
                     long maxExecutionTime,
                     java.lang.String endMark)

NativeCommand

public NativeCommand(java.lang.String command,
                     boolean foreground,
                     long maxExecutionTime,
                     java.lang.String endMark,
                     long interval,
                     long delay)

Method Detail

setThreadFactory

public void setThreadFactory(java.util.concurrent.ThreadFactory threads)

This class executes various actions concurrently. With this setter, clients can control the threads to be used.

Parameters:

threads - - null for default

addListener

public void addListener(NativeCommand.Listener po)

removeListener

public void removeListener(NativeCommand.Listener po)

getStatus

public java.lang.String getStatus()

getExitValue

public java.lang.Integer getExitValue()

Returns:

null if no exit value due to ungraceful process death

getLatestException

public java.lang.Throwable getLatestException()

Returns the most recent occured error. Note that the internal exception cache is reset by this method, thus it can only be called once for each error.

Returns:

send

public void send(java.lang.String text)

Writes the given text to the STDIN of the process.

Parameters:

text - the input to send to the process

run

public void run()

We use four delegates:

1. One to start a process
2. One to watch its progress
3. Two to read its output (out and err)

The delegates give feedback to the main thread by provoking InterruptedExceptions on it.

Specified by:

run in interface java.lang.Runnable

changeStatus

protected void changeStatus(java.lang.String newStatus)

fireStatusChanged

protected void fireStatusChanged(java.lang.String oldStatus,
                                 java.lang.String newStatus)

fireOutputWritten

protected void fireOutputWritten(java.io.InputStream sourceStream,
                                 java.lang.String additionalOutput)