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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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*
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* accompanied this code).
*
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*
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package javax.management.openmbean;
// java import
//
import java.util.Arrays;
import java.util.HashSet;
import java.util.Objects;
import javax.management.Descriptor;
import javax.management.MBeanAttributeInfo;
import javax.management.MBeanConstructorInfo;
import javax.management.MBeanInfo;
import javax.management.MBeanNotificationInfo;
import javax.management.MBeanOperationInfo;
The OpenMBeanInfoSupport
class describes the management information of an open MBean: it is a subclass of MBeanInfo
, and it implements the OpenMBeanInfo
interface. Note that an open MBean is recognized as such if its getMBeanInfo()
method returns an instance of a class which implements the OpenMBeanInfo interface, typically OpenMBeanInfoSupport
. Since: 1.5
/**
* The {@code OpenMBeanInfoSupport} class describes the management
* information of an <i>open MBean</i>: it is a subclass of {@link
* javax.management.MBeanInfo}, and it implements the {@link
* OpenMBeanInfo} interface. Note that an <i>open MBean</i> is
* recognized as such if its {@code getMBeanInfo()} method returns an
* instance of a class which implements the OpenMBeanInfo interface,
* typically {@code OpenMBeanInfoSupport}.
*
*
* @since 1.5
*/
public class OpenMBeanInfoSupport
extends MBeanInfo
implements OpenMBeanInfo {
/* Serial version */
static final long serialVersionUID = 4349395935420511492L;
// As this instance is immutable, these two values
// need only be calculated once.
private transient Integer myHashCode = null;
private transient String myToString = null;
Constructs an OpenMBeanInfoSupport
instance, which describes a class of open MBeans with the specified
className
, description
, openAttributes
,
openConstructors
, openOperations
and
notifications
.
The openAttributes
, openConstructors
, openOperations
and notifications
array parameters are internally copied, so that subsequent changes to the arrays referenced by these parameters have no effect on this instance.
Params: - className – The fully qualified Java class name of the
open MBean described by this
OpenMBeanInfoSupport
instance. - description – A human readable description of the open
MBean described by this
OpenMBeanInfoSupport
instance. - openAttributes – The list of exposed attributes of the described open MBean; Must be an array of instances of a subclass of
MBeanAttributeInfo
, typically
OpenMBeanAttributeInfoSupport
. - openConstructors – The list of exposed public constructors of the described open MBean; Must be an array of instances of a subclass of
MBeanConstructorInfo
, typically
OpenMBeanConstructorInfoSupport
. - openOperations – The list of exposed operations of the described open MBean. Must be an array of instances of a subclass of
MBeanOperationInfo
, typically
OpenMBeanOperationInfoSupport
. - notifications – The list of notifications emitted by the
described open MBean.
Throws: - ArrayStoreException – If
openAttributes
,
openConstructors
or openOperations
is not an array of instances of a subclass of MBeanAttributeInfo
,
MBeanConstructorInfo
or MBeanOperationInfo
respectively.
/**
* <p>Constructs an {@code OpenMBeanInfoSupport} instance, which
* describes a class of open MBeans with the specified {@code
* className}, {@code description}, {@code openAttributes}, {@code
* openConstructors} , {@code openOperations} and {@code
* notifications}.</p>
*
* <p>The {@code openAttributes}, {@code openConstructors},
* {@code openOperations} and {@code notifications}
* array parameters are internally copied, so that subsequent changes
* to the arrays referenced by these parameters have no effect on this
* instance.</p>
*
* @param className The fully qualified Java class name of the
* open MBean described by this <CODE>OpenMBeanInfoSupport</CODE>
* instance.
*
* @param description A human readable description of the open
* MBean described by this <CODE>OpenMBeanInfoSupport</CODE>
* instance.
*
* @param openAttributes The list of exposed attributes of the
* described open MBean; Must be an array of instances of a
* subclass of {@code MBeanAttributeInfo}, typically {@code
* OpenMBeanAttributeInfoSupport}.
*
* @param openConstructors The list of exposed public constructors
* of the described open MBean; Must be an array of instances of a
* subclass of {@code MBeanConstructorInfo}, typically {@code
* OpenMBeanConstructorInfoSupport}.
*
* @param openOperations The list of exposed operations of the
* described open MBean. Must be an array of instances of a
* subclass of {@code MBeanOperationInfo}, typically {@code
* OpenMBeanOperationInfoSupport}.
*
* @param notifications The list of notifications emitted by the
* described open MBean.
*
* @throws ArrayStoreException If {@code openAttributes}, {@code
* openConstructors} or {@code openOperations} is not an array of
* instances of a subclass of {@code MBeanAttributeInfo}, {@code
* MBeanConstructorInfo} or {@code MBeanOperationInfo}
* respectively.
*/
public OpenMBeanInfoSupport(String className,
String description,
OpenMBeanAttributeInfo[] openAttributes,
OpenMBeanConstructorInfo[] openConstructors,
OpenMBeanOperationInfo[] openOperations,
MBeanNotificationInfo[] notifications) {
this(className, description,
openAttributes, openConstructors, openOperations, notifications,
(Descriptor) null);
}
Constructs an OpenMBeanInfoSupport
instance, which describes a class of open MBeans with the specified
className
, description
, openAttributes
,
openConstructors
, openOperations
,
notifications
, and descriptor
.
The openAttributes
, openConstructors
,
openOperations
and notifications
array parameters are internally copied, so that subsequent changes to the arrays referenced by these parameters have no effect on this instance.
Params: - className – The fully qualified Java class name of the
open MBean described by this
OpenMBeanInfoSupport
instance. - description – A human readable description of the open
MBean described by this
OpenMBeanInfoSupport
instance. - openAttributes – The list of exposed attributes of the described open MBean; Must be an array of instances of a subclass of
MBeanAttributeInfo
, typically
OpenMBeanAttributeInfoSupport
. - openConstructors – The list of exposed public constructors of the described open MBean; Must be an array of instances of a subclass of
MBeanConstructorInfo
, typically
OpenMBeanConstructorInfoSupport
. - openOperations – The list of exposed operations of the described open MBean. Must be an array of instances of a subclass of
MBeanOperationInfo
, typically
OpenMBeanOperationInfoSupport
. - notifications – The list of notifications emitted by the
described open MBean.
- descriptor – The descriptor for the MBean. This may be null
which is equivalent to an empty descriptor.
Throws: - ArrayStoreException – If
openAttributes
,
openConstructors
or openOperations
is not an array of instances of a subclass of MBeanAttributeInfo
,
MBeanConstructorInfo
or MBeanOperationInfo
respectively.
Since: 1.6
/**
* <p>Constructs an {@code OpenMBeanInfoSupport} instance, which
* describes a class of open MBeans with the specified {@code
* className}, {@code description}, {@code openAttributes}, {@code
* openConstructors} , {@code openOperations}, {@code
* notifications}, and {@code descriptor}.</p>
*
* <p>The {@code openAttributes}, {@code openConstructors}, {@code
* openOperations} and {@code notifications} array parameters are
* internally copied, so that subsequent changes to the arrays
* referenced by these parameters have no effect on this
* instance.</p>
*
* @param className The fully qualified Java class name of the
* open MBean described by this <CODE>OpenMBeanInfoSupport</CODE>
* instance.
*
* @param description A human readable description of the open
* MBean described by this <CODE>OpenMBeanInfoSupport</CODE>
* instance.
*
* @param openAttributes The list of exposed attributes of the
* described open MBean; Must be an array of instances of a
* subclass of {@code MBeanAttributeInfo}, typically {@code
* OpenMBeanAttributeInfoSupport}.
*
* @param openConstructors The list of exposed public constructors
* of the described open MBean; Must be an array of instances of a
* subclass of {@code MBeanConstructorInfo}, typically {@code
* OpenMBeanConstructorInfoSupport}.
*
* @param openOperations The list of exposed operations of the
* described open MBean. Must be an array of instances of a
* subclass of {@code MBeanOperationInfo}, typically {@code
* OpenMBeanOperationInfoSupport}.
*
* @param notifications The list of notifications emitted by the
* described open MBean.
*
* @param descriptor The descriptor for the MBean. This may be null
* which is equivalent to an empty descriptor.
*
* @throws ArrayStoreException If {@code openAttributes}, {@code
* openConstructors} or {@code openOperations} is not an array of
* instances of a subclass of {@code MBeanAttributeInfo}, {@code
* MBeanConstructorInfo} or {@code MBeanOperationInfo}
* respectively.
*
* @since 1.6
*/
public OpenMBeanInfoSupport(String className,
String description,
OpenMBeanAttributeInfo[] openAttributes,
OpenMBeanConstructorInfo[] openConstructors,
OpenMBeanOperationInfo[] openOperations,
MBeanNotificationInfo[] notifications,
Descriptor descriptor) {
super(className,
description,
attributeArray(openAttributes),
constructorArray(openConstructors),
operationArray(openOperations),
(notifications == null) ? null : notifications.clone(),
descriptor);
}
private static MBeanAttributeInfo[]
attributeArray(OpenMBeanAttributeInfo[] src) {
if (src == null)
return null;
MBeanAttributeInfo[] dst = new MBeanAttributeInfo[src.length];
System.arraycopy(src, 0, dst, 0, src.length);
// may throw an ArrayStoreException
return dst;
}
private static MBeanConstructorInfo[]
constructorArray(OpenMBeanConstructorInfo[] src) {
if (src == null)
return null;
MBeanConstructorInfo[] dst = new MBeanConstructorInfo[src.length];
System.arraycopy(src, 0, dst, 0, src.length);
// may throw an ArrayStoreException
return dst;
}
private static MBeanOperationInfo[]
operationArray(OpenMBeanOperationInfo[] src) {
if (src == null)
return null;
MBeanOperationInfo[] dst = new MBeanOperationInfo[src.length];
System.arraycopy(src, 0, dst, 0, src.length);
return dst;
}
/* *** Commodity methods from java.lang.Object *** */
Compares the specified obj
parameter with this OpenMBeanInfoSupport
instance for equality.
Returns true
if and only if all of the following statements are true:
obj
is non null,
obj
also implements the OpenMBeanInfo
interface,
- their class names are equal
- their infos on attributes, constructors, operations and
notifications are equal
This ensures that this equals
method works properly for obj
parameters which are different implementations of the OpenMBeanInfo
interface. Params: - obj – the object to be compared for equality with this
OpenMBeanInfoSupport
instance;
Returns: true
if the specified object is equal to this OpenMBeanInfoSupport
instance.
/**
* <p>Compares the specified {@code obj} parameter with this
* {@code OpenMBeanInfoSupport} instance for equality.</p>
*
* <p>Returns {@code true} if and only if all of the following
* statements are true:
*
* <ul>
* <li>{@code obj} is non null,</li>
* <li>{@code obj} also implements the {@code OpenMBeanInfo}
* interface,</li>
* <li>their class names are equal</li>
* <li>their infos on attributes, constructors, operations and
* notifications are equal</li>
* </ul>
*
* This ensures that this {@code equals} method works properly for
* {@code obj} parameters which are different implementations of
* the {@code OpenMBeanInfo} interface.
*
* @param obj the object to be compared for equality with this
* {@code OpenMBeanInfoSupport} instance;
*
* @return {@code true} if the specified object is equal to this
* {@code OpenMBeanInfoSupport} instance.
*/
public boolean equals(Object obj) {
// if obj is null, return false
//
if (obj == null) {
return false;
}
// if obj is not a OpenMBeanInfo, return false
//
OpenMBeanInfo other;
try {
other = (OpenMBeanInfo) obj;
} catch (ClassCastException e) {
return false;
}
// Now, really test for equality between this OpenMBeanInfo
// implementation and the other:
//
// their MBean className should be equal
if (!Objects.equals(this.getClassName(), other.getClassName())) {
return false;
}
// their infos on attributes should be equal (order not
// significant => equality between sets, not arrays or lists)
if (!sameArrayContents(this.getAttributes(), other.getAttributes()))
return false;
// their infos on constructors should be equal (order not
// significant => equality between sets, not arrays or lists)
if (!sameArrayContents(this.getConstructors(), other.getConstructors()))
return false;
// their infos on operations should be equal (order not
// significant => equality between sets, not arrays or lists)
if (!sameArrayContents(this.getOperations(), other.getOperations()))
return false;
// their infos on notifications should be equal (order not
// significant => equality between sets, not arrays or lists)
if (!sameArrayContents(this.getNotifications(), other.getNotifications()))
return false;
// All tests for equality were successful
//
return true;
}
private static <T> boolean sameArrayContents(T[] a1, T[] a2) {
return (new HashSet<T>(Arrays.asList(a1))
.equals(new HashSet<T>(Arrays.asList(a2))));
}
Returns the hash code value for this
OpenMBeanInfoSupport
instance.
The hash code of an OpenMBeanInfoSupport
instance is the sum of the hash codes of all elements of information used in equals
comparisons (ie: its class name, and its infos on attributes, constructors, operations and notifications, where the hashCode of each of these arrays is calculated by a call to new
java.util.HashSet(java.util.Arrays.asList(this.getSignature)).hashCode()
).
This ensures that t1.equals(t2)
implies that
t1.hashCode()==t2.hashCode()
for any two
OpenMBeanInfoSupport
instances t1
and t2
, as required by the general contract of the method Object.hashCode()
.
However, note that another instance of a class implementing the OpenMBeanInfo
interface may be equal to this
OpenMBeanInfoSupport
instance as defined by equals(Object)
, but may have a different hash code if it is calculated differently.
As OpenMBeanInfoSupport
instances are immutable, the hash code for this instance is calculated once, on the first call to hashCode
, and then the same value is returned for subsequent calls.
Returns: the hash code value for this
OpenMBeanInfoSupport
instance
/**
* <p>Returns the hash code value for this {@code
* OpenMBeanInfoSupport} instance.</p>
*
* <p>The hash code of an {@code OpenMBeanInfoSupport} instance is
* the sum of the hash codes of all elements of information used
* in {@code equals} comparisons (ie: its class name, and its
* infos on attributes, constructors, operations and
* notifications, where the hashCode of each of these arrays is
* calculated by a call to {@code new
* java.util.HashSet(java.util.Arrays.asList(this.getSignature)).hashCode()}).</p>
*
* <p>This ensures that {@code t1.equals(t2)} implies that {@code
* t1.hashCode()==t2.hashCode()} for any two {@code
* OpenMBeanInfoSupport} instances {@code t1} and {@code t2}, as
* required by the general contract of the method {@link
* Object#hashCode() Object.hashCode()}.</p>
*
* <p>However, note that another instance of a class implementing
* the {@code OpenMBeanInfo} interface may be equal to this {@code
* OpenMBeanInfoSupport} instance as defined by {@link
* #equals(java.lang.Object)}, but may have a different hash code
* if it is calculated differently.</p>
*
* <p>As {@code OpenMBeanInfoSupport} instances are immutable, the
* hash code for this instance is calculated once, on the first
* call to {@code hashCode}, and then the same value is returned
* for subsequent calls.</p>
*
* @return the hash code value for this {@code
* OpenMBeanInfoSupport} instance
*/
public int hashCode() {
// Calculate the hash code value if it has not yet been done
// (ie 1st call to hashCode())
//
if (myHashCode == null) {
int value = 0;
if (this.getClassName() != null) {
value += this.getClassName().hashCode();
}
value += arraySetHash(this.getAttributes());
value += arraySetHash(this.getConstructors());
value += arraySetHash(this.getOperations());
value += arraySetHash(this.getNotifications());
myHashCode = Integer.valueOf(value);
}
// return always the same hash code for this instance (immutable)
//
return myHashCode.intValue();
}
private static <T> int arraySetHash(T[] a) {
return new HashSet<T>(Arrays.asList(a)).hashCode();
}
Returns a string representation of this
OpenMBeanInfoSupport
instance.
The string representation consists of the name of this class (ie javax.management.openmbean.OpenMBeanInfoSupport
), the MBean class name, the string representation of infos on attributes, constructors, operations and notifications of the described MBean and the string representation of the descriptor.
As OpenMBeanInfoSupport
instances are immutable, the string representation for this instance is calculated once, on the first call to toString
, and then the same value is returned for subsequent calls.
Returns: a string representation of this
OpenMBeanInfoSupport
instance
/**
* <p>Returns a string representation of this {@code
* OpenMBeanInfoSupport} instance.</p>
*
* <p>The string representation consists of the name of this class
* (ie {@code javax.management.openmbean.OpenMBeanInfoSupport}),
* the MBean class name, the string representation of infos on
* attributes, constructors, operations and notifications of the
* described MBean and the string representation of the descriptor.</p>
*
* <p>As {@code OpenMBeanInfoSupport} instances are immutable, the
* string representation for this instance is calculated once, on
* the first call to {@code toString}, and then the same value is
* returned for subsequent calls.</p>
*
* @return a string representation of this {@code
* OpenMBeanInfoSupport} instance
*/
public String toString() {
// Calculate the string value if it has not yet been done (ie
// 1st call to toString())
//
if (myToString == null) {
myToString = new StringBuilder()
.append(this.getClass().getName())
.append("(mbean_class_name=")
.append(this.getClassName())
.append(",attributes=")
.append(Arrays.asList(this.getAttributes()).toString())
.append(",constructors=")
.append(Arrays.asList(this.getConstructors()).toString())
.append(",operations=")
.append(Arrays.asList(this.getOperations()).toString())
.append(",notifications=")
.append(Arrays.asList(this.getNotifications()).toString())
.append(",descriptor=")
.append(this.getDescriptor())
.append(")")
.toString();
}
// return always the same string representation for this
// instance (immutable)
//
return myToString;
}
}