OpenJDK 1.23 · com.sun.tools.attach.VirtualMachineDescriptor

Describes a Java virtual machine.

A VirtualMachineDescriptor is a container class used to describe a Java virtual machine. It encapsulates an identifier that identifies a target virtual machine, and a reference to the AttachProvider that should be used when attempting to attach to the virtual machine. The identifier is implementation-dependent but is typically the process identifier (or pid) environments where each Java virtual machine runs in its own operating system process.

A VirtualMachineDescriptor also has a displayName. The display name is typically a human readable string that a tool might display to a user. For example, a tool that shows a list of Java virtual machines running on a system might use the display name rather than the identifier. A VirtualMachineDescriptor may be created without a display name. In that case the identifier is used as the display name.

VirtualMachineDescriptor instances are typically created by invoking the VirtualMachine.list() method. This returns the complete list of descriptors to describe the Java virtual machines known to all installed attach providers.

Modifier and Type	Field and Description
private String	displayName
private volatile int	hash
private String	id
private AttachProvider	provider

Constructor Summary

Access	Constructor and Description
public	VirtualMachineDescriptor(AttachProvider The AttachProvider to attach to the Java virtual machine. provider, String The virtual machine identifier. id, String The display name. displayName) Creates a virtual machine descriptor from the given components.
public	VirtualMachineDescriptor(AttachProvider The AttachProvider to attach to the Java virtual machine. provider, String The virtual machine identifier. id) Creates a virtual machine descriptor from the given components.

Method Summary

Modifier and Type	Method and Description
public String	Returns: The display name component of this descriptor. displayName() Return the display name component of this descriptor.
public boolean	Returns: `true` if, and only if, the given object is a VirtualMachineDescriptor that is equal to this VirtualMachineDescriptor. equals(Object The object to which this object is to be compared ob) Overrides java.lang.Object.equals. Tests this VirtualMachineDescriptor for equality with another object.
public int	Returns: A hash-code value for this descriptor. hashCode() Overrides java.lang.Object.hashCode. Returns a hash-code value for this VirtualMachineDescriptor.
public String	Returns: The identifier component of this descriptor. id() Return the identifier component of this descriptor.
public AttachProvider	Returns: The `AttachProvider` that this descriptor references. provider() Return the `AttachProvider` that this descriptor references.
public String	toString() Overrides java.lang.Object.toString. Returns the string representation of the `VirtualMachineDescriptor`.

Inherited from java.lang.Object:: clone finalize getClass notify notifyAll wait wait wait

Field Detail

displayName	back to summary
private String displayName

hash	back to summary
private volatile int hash

id	back to summary
private String id

provider	back to summary
private AttachProvider provider

Constructor Detail

VirtualMachineDescriptor back to summary

VirtualMachineDescriptor	back to summary
public VirtualMachineDescriptor(AttachProvider provider, String id, String displayName) Creates a virtual machine descriptor from the given components. Parameters provider:AttachProvider The AttachProvider to attach to the Java virtual machine. id:String The virtual machine identifier. displayName:String The display name. Exceptions NullPointerException: If any of the arguments are `null`

public VirtualMachineDescriptor(AttachProvider provider, String id, String displayName)

Creates a virtual machine descriptor from the given components.

Parameters

provider:AttachProvider: The AttachProvider to attach to the Java virtual machine.
id:String: The virtual machine identifier.
displayName:String: The display name.

Exceptions

NullPointerException:: If any of the arguments are null

VirtualMachineDescriptor back to summary

VirtualMachineDescriptor	back to summary
public VirtualMachineDescriptor(AttachProvider provider, String id) Creates a virtual machine descriptor from the given components. This convenience constructor works as if by invoking the three-argument constructor as follows: `new VirtualMachineDescriptor(provider, id, id);` That is, it creates a virtual machine descriptor such that the display name is the same as the virtual machine identifier. Parameters provider:AttachProvider The AttachProvider to attach to the Java virtual machine. id:String The virtual machine identifier. Exceptions NullPointerException: If `provider` or `id` is `null`.

public VirtualMachineDescriptor(AttachProvider provider, String id)

Creates a virtual machine descriptor from the given components.

This convenience constructor works as if by invoking the three-argument constructor as follows:

new VirtualMachineDescriptor(provider, id, id);

That is, it creates a virtual machine descriptor such that the display name is the same as the virtual machine identifier.

Parameters

provider:AttachProvider: The AttachProvider to attach to the Java virtual machine.
id:String: The virtual machine identifier.

Exceptions

NullPointerException:: If provider or id is null.

Method Detail

displayName	back to summary
public String displayName() Return the display name component of this descriptor. Returns:String The display name component of this descriptor.

displayName

back to summary

public String displayName()

Return the display name component of this descriptor.

Returns:String: The display name component of this descriptor.

equals back to summary

equals	back to summary
public boolean equals(Object ob) Overrides java.lang.Object.equals. Tests this VirtualMachineDescriptor for equality with another object. If the given object is not a VirtualMachineDescriptor then this method returns `false`. For two VirtualMachineDescriptors to be considered equal requires that they both reference the same provider, and their `identifiers` are equal. This method satisfies the general contract of the `Object.equals` method. Parameters ob:Object The object to which this object is to be compared Returns:boolean `true` if, and only if, the given object is a VirtualMachineDescriptor that is equal to this VirtualMachineDescriptor.

public boolean equals(Object ob)

Overrides java.lang.Object.equals.

Tests this VirtualMachineDescriptor for equality with another object.

If the given object is not a VirtualMachineDescriptor then this method returns false. For two VirtualMachineDescriptors to be considered equal requires that they both reference the same provider, and their identifiers are equal.

This method satisfies the general contract of the Object.equals method.

Parameters

ob:Object: The object to which this object is to be compared

Returns:boolean

true if, and only if, the given object is a VirtualMachineDescriptor that is equal to this VirtualMachineDescriptor.

hashCode back to summary

hashCode	back to summary
public int hashCode() Overrides java.lang.Object.hashCode. Returns a hash-code value for this VirtualMachineDescriptor. The hash code is based upon the descriptor's components, and satisfies the general contract of the `Object.hashCode` method. Returns:int A hash-code value for this descriptor.

public int hashCode()

Overrides java.lang.Object.hashCode.

Returns a hash-code value for this VirtualMachineDescriptor. The hash code is based upon the descriptor's components, and satisfies the general contract of the Object.hashCode method.

Returns:int: A hash-code value for this descriptor.

id	back to summary
public String id() Return the identifier component of this descriptor. Returns:String The identifier component of this descriptor.

back to summary

public String id()

Return the identifier component of this descriptor.

Returns:String: The identifier component of this descriptor.

provider back to summary

provider	back to summary
public AttachProvider provider() Return the `AttachProvider` that this descriptor references. Returns:AttachProvider The `AttachProvider` that this descriptor references.

public AttachProvider provider()

Return the AttachProvider that this descriptor references.

Returns:AttachProvider: The AttachProvider that this descriptor references.

toString back to summary

toString	back to summary
public String toString() Overrides java.lang.Object.toString. Returns the string representation of the `VirtualMachineDescriptor`. Returns:String Doc from java.lang.Object.toString. a string representation of the object

public String toString()

Overrides java.lang.Object.toString.

Returns the string representation of the VirtualMachineDescriptor.

Returns:String

Doc from java.lang.Object.toString.

a string representation of the object

public Class VirtualMachineDescriptor

Field Summary

Constructor Summary

Method Summary

Field Detail

Constructor Detail

Method Detail