public class VMOption extends Object
origin
.
Each VM option has a default value. A VM option can
be set at VM creation time typically as a command line
argument to the launcher or an argument passed to the
VM created using the JNI invocation interface.
In addition, a VM option may be set via an environment
variable or a configuration file. A VM option can also
be set dynamically via a management interface after
the VM was started.
A VMOption
contains the value of a VM option
and the origin of that value at the time this VMOption
object was constructed. The value of the VM option
may be changed after the VMOption
object was constructed,
Modifier and Type | Class | Description |
---|---|---|
static class |
VMOption.Origin |
Origin of the value of a VM option.
|
Constructor | Description |
---|---|
VMOption(String name,
String value,
boolean writeable,
VMOption.Origin origin) |
Constructs a
VMOption . |
Modifier and Type | Method | Description |
---|---|---|
static VMOption |
from(CompositeData cd) |
Returns a
VMOption object represented by the
given CompositeData . |
String |
getName() |
Returns the name of this VM option.
|
VMOption.Origin |
getOrigin() |
Returns the origin of the value of this VM option.
|
String |
getValue() |
Returns the value of this VM option at the time when
this
VMOption was created. |
boolean |
isWriteable() |
Tests if this VM option is writeable.
|
String |
toString() |
Returns a string representation of the object.
|
public VMOption(String name, String value, boolean writeable, VMOption.Origin origin)
VMOption
.name
- Name of a VM option.value
- Value of a VM option.writeable
- true
if a VM option can be set dynamically,
or false
otherwise.origin
- where the value of a VM option came from.NullPointerException
- if the name or value is null
public String getName()
public String getValue()
VMOption
was created. The value could have been changed.VMOption
was created.public VMOption.Origin getOrigin()
public boolean isWriteable()
HotSpotDiagnosticMXBean.setVMOption
method.true
if this VM option is writeable; false
otherwise.public String toString()
java.lang.Object
toString
method returns a string that
"textually represents" this object. The result should
be a concise but informative representation that is easy for a
person to read.
It is recommended that all subclasses override this method.
The toString
method for class Object
returns a string consisting of the name of the class of which the
object is an instance, the at-sign character `@
', and
the unsigned hexadecimal representation of the hash code of the
object. In other words, this method returns a string equal to the
value of:
getClass().getName() + '@' + Integer.toHexString(hashCode())
public static VMOption from(CompositeData cd)
VMOption
object represented by the
given CompositeData
. The given CompositeData
must contain the following attributes:
Attribute Name Type name java.lang.String
value java.lang.String
origin java.lang.String
writeable java.lang.Boolean
cd
- CompositeData
representing a VMOption
VMOption
object represented by cd
if cd
is not null
;
null
otherwise.IllegalArgumentException
- if cd
does not
represent a VMOption
with the attributes described
above. Submit a bug or feature
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DRAFT 9-Ubuntu+0-9b149-1