javax.realtime

Class ConfigurationParameters

java.lang.Object

javax.realtime.ConfigurationParameters

All Implemented Interfaces:

Serializable, Cloneable

public class ConfigurationParameters
extends Object
implements Cloneable, Serializable

Configuration parameters provide a way to specify various implementation-dependent parameters such as the Java stack and native stack sizes, and to configure the statically allocated ThrowBoundaryError associated with a Schedulable.

Note that these parameters are immutable.

Since JamaicaVM has a fixed block size for object, the default for the string parametes, class name length, method name length, and file name length, should be chosen to optimally use the space reserved. For instance, in the case of contiguous array, a string length of 25 will use a full block more than one of 24, or 32 more bytes. The next effective size is 40 characters. When stored as tree arrays both these values use one additional block. This is true up to 56 charaters. Longer sizes are generally not required. In general, class names are longer than method or file names, since they include its package name. The equivalent number of frame count are 12, 20, and 48.

Since:

RTSJ 2.0

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor and Description
ConfigurationParameters(int messageLength, int stackTraceDepth, int classNameLength, int methodNameLength, int fileNameLength, long[] sizes) Creates a parameter object for initializing the state of a Schedulable.
ConfigurationParameters(long[] sizes) Same as ConfigurationParameters(int,int,int,int,int,long[]) with arguments (0, 0, 0, 0, 0, sizes).

Method Summary

Modifier and Type	Method and Description
int	getClassNameLength() Obtain the maximum number of character available for storing class names in each stack trace frame.
static ConfigurationParameters	getDefault() Set the parameters object to be used when none is provided for an instance of Schedulable.
static ReleaseRunner	getDefaultRunner() Gets the system default release runner.
int	getFileNameLength() Obtain the maximum number of character available for storing file names in each stack trace frame.
int	getMessageLength() Obtain the size of the buffer dedicated to storing the message of the last thrown throwable in the context of instances of Schedulable created with these parameters.
int	getMethodNameLength() Obtain the maximum number of character available for storing method signatures in each stack trace frame.
long[]	getSizes() Gets the array of implementation-specific sizes associated with Schedulable objects created with these parameters.
int	getStackTraceDepth() Obtain the number of frames available for storing the stack trace of the last thrown throwable in the context of instances of Schedulable created with these parameters.
static void	setDefault(ConfigurationParameters config) Set the parameters object to be used when none is provided for an instance of Schedulable.
static void	setDefaultRunner(ReleaseRunner runner) Sets the system default release runner.

Methods inherited from class java.lang.Object

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

Constructor Detail

ConfigurationParameters

public ConfigurationParameters(int messageLength,
                               int stackTraceDepth,
                               int classNameLength,
                               int methodNameLength,
                               int fileNameLength,
                               long[] sizes)
                        throws StaticIllegalStateException

Creates a parameter object for initializing the state of a Schedulable. The parameters provide the data for this initialization. For RealtimeThread and bound versions of AsyncBaseEventHandler, the stack and message buffers can be set exactly, but for the unbound event handlers, the system cannot give any guarentees to allow thread sharing.

Throws:

StaticIllegalStateException

Parameters:

messageLength - The size of the buffer, in units of char, for storing an exception message used by preallocated exceptions and errors thrown in the context of an instance of Schedulable which was created with this as its configuration parameters. The value 0 indicates that no message should be stored. The value of -1 uses the system default and is the default when an instance of this class is not provided.

stackTraceDepth - The number of stack trace elements, reserved for use by preallocated exceptions and errors thrown in the execution context of the Schedulable object created with these parameters. The amount of space this requires is implementation-specific. The value 0 indicates that no stack trace should be stored. The value of -1 uses the system default and is the default when an instance of this class is not provided.

classNameLength - The number of characters reserved in each frame for saving the full class name in a given stack trace frame.

methodNameLength - The number of characters reserved in each frame for saving the method signature in a given stack trace frame.

fileNameLength - The number of characters reserved in each frame for saving the file name in a given stack trace frame.

sizes - An array of implementation-specific values dictating memory parameters for Schedulable objects created with these parameters, such as maximum Java and native stack sizes. The sizes array will not be stored in the constructed object. The default is system dependent, and indicated by setting this parameter to null or by not providing an instance of this class.

JamaicaVM: not yet used.

ConfigurationParameters

public ConfigurationParameters(long[] sizes)

Same as ConfigurationParameters(int,int,int,int,int,long[]) with arguments (0, 0, 0, 0, 0, sizes).

Method Detail

setDefault

public static void setDefault(ConfigurationParameters config)

Set the parameters object to be used when none is provided for an instance of Schedulable. Setting to null restores the default values.

Parameters:

config - the new default parameter object.

getDefault

public static ConfigurationParameters getDefault()

Set the parameters object to be used when none is provided for an instance of Schedulable.

Returns:

the default parameter object.

setDefaultRunner

public static void setDefaultRunner(ReleaseRunner runner)

Sets the system default release runner.

Parameters:

runner - The runner to be used when none is set. When null, the default release runner is set to the original system default.

getDefaultRunner

public static ReleaseRunner getDefaultRunner()

Gets the system default release runner.

Returns:

a general runner to be used when none is set.

getMessageLength

public int getMessageLength()

Obtain the size of the buffer dedicated to storing the message of the last thrown throwable in the context of instances of Schedulable created with these parameters. The value 0 indicates that no message will be stored.

Returns:

reserved memory in units of char.

getStackTraceDepth

public int getStackTraceDepth()

Obtain the number of frames available for storing the stack trace of the last thrown throwable in the context of instances of Schedulable created with these parameters. The value 0 indicates that no stack trace will be stored.

Returns:

reserved memory as number of frames to save.

getClassNameLength

public int getClassNameLength()

Obtain the maximum number of character available for storing class names in each stack trace frame.

Returns:

reserved memory in units of char.

getMethodNameLength

public int getMethodNameLength()

Obtain the maximum number of character available for storing method signatures in each stack trace frame.

Returns:

reserved memory in units of char.

getFileNameLength

public int getFileNameLength()

Obtain the maximum number of character available for storing file names in each stack trace frame.

Returns:

reserved memory in units of char.

getSizes

public long[] getSizes()

Gets the array of implementation-specific sizes associated with Schedulable objects created with these parameters. This method may allocate memory.

Returns:

a copy of the array of implementation-specific sizes or null when none are set.