compact3

javax.management.modelmbean

Class DescriptorSupport

java.lang.Object

javax.management.modelmbean.DescriptorSupport

All Implemented Interfaces:

Serializable, Cloneable, Descriptor

public class DescriptorSupport
extends Object
implements Descriptor

This class represents the metadata set for a ModelMBean element. A descriptor is part of the ModelMBeanInfo, ModelMBeanNotificationInfo, ModelMBeanAttributeInfo, ModelMBeanConstructorInfo, and ModelMBeanParameterInfo.

A descriptor consists of a collection of fields. Each field is in fieldname=fieldvalue format. Field names are not case sensitive, case will be preserved on field values.

All field names and values are not predefined. New fields can be defined and added by any program. Some fields have been predefined for consistency of implementation and support by the ModelMBeanInfo, ModelMBeanAttributeInfo, ModelMBeanConstructorInfo, ModelMBeanNotificationInfo, ModelMBeanOperationInfo and ModelMBean classes.

The serialVersionUID of this class is -6292969195866300415L.

Since:

1.5

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor	Description
DescriptorSupport()	Descriptor default constructor.
DescriptorSupport(DescriptorSupport inDescr)	Descriptor constructor taking a Descriptor as parameter.
DescriptorSupport(int initNumFields)	Descriptor constructor.
DescriptorSupport(String... fields)	Constructor taking fields in the fieldName=fieldValue format.
DescriptorSupport(String inStr)	Descriptor constructor taking an XML String.
DescriptorSupport(String[] fieldNames, Object[] fieldValues)	Constructor taking field names and field values.

Method Summary

Modifier and Type	Method	Description
Object	clone()	Returns a new Descriptor which is a duplicate of the Descriptor.
boolean	equals(Object o)	Compares this descriptor to the given object.
String[]	getFieldNames()	Returns all the field names in the descriptor.
String[]	getFields()	Returns all of the fields contained in this descriptor as a string array.
Object	getFieldValue(String fieldName)	Returns the value for a specific field name, or null if no value is present for that name.
Object[]	getFieldValues(String... fieldNames)	Returns all the field values in the descriptor as an array of Objects.
int	hashCode()	Returns the hash code value for this descriptor.
boolean	isValid()	Returns true if all of the fields have legal values given their names.
void	removeField(String fieldName)	Removes a field from the descriptor.
void	setField(String fieldName, Object fieldValue)	Sets the value for a specific field name.
void	setFields(String[] fieldNames, Object[] fieldValues)	Sets all fields in the field names array to the new value with the same index in the field values array.
String	toString()	Returns a human readable string representing the descriptor.
String	toXMLString()	Returns an XML String representing the descriptor.

Methods inherited from class java.lang.Object

finalize, getClass, notify, notifyAll, wait, wait, wait

Constructor Detail

DescriptorSupport

public DescriptorSupport()

Descriptor default constructor. Default initial descriptor size is 20. It will grow as needed.
Note that the created empty descriptor is not a valid descriptor (the method isValid returns false)

DescriptorSupport

public DescriptorSupport(int initNumFields)
                  throws MBeanException,
                         RuntimeOperationsException

Descriptor constructor. Takes as parameter the initial capacity of the Map that stores the descriptor fields. Capacity will grow as needed.
Note that the created empty descriptor is not a valid descriptor (the method isValid returns false).

Parameters:

initNumFields - The initial capacity of the Map that stores the descriptor fields.

Throws:

RuntimeOperationsException - for illegal value for initNumFields (<= 0)

MBeanException - Wraps a distributed communication Exception.

DescriptorSupport

public DescriptorSupport(DescriptorSupport inDescr)

Descriptor constructor taking a Descriptor as parameter. Creates a new descriptor initialized to the values of the descriptor passed in parameter.

Parameters:

inDescr - the descriptor to be used to initialize the constructed descriptor. If it is null or contains no descriptor fields, an empty Descriptor will be created.

DescriptorSupport

public DescriptorSupport(String inStr)
                  throws MBeanException,
                         RuntimeOperationsException,
                         XMLParseException

Descriptor constructor taking an XML String.

The format of the XML string is not defined, but an implementation must ensure that the string returned by toXMLString() on an existing descriptor can be used to instantiate an equivalent descriptor using this constructor.

In this implementation, all field values will be created as Strings. If the field values are not Strings, the programmer will have to reset or convert these fields correctly.

Parameters:

inStr - An XML-formatted string used to populate this Descriptor. The format is not defined, but any implementation must ensure that the string returned by method toXMLString on an existing descriptor can be used to instantiate an equivalent descriptor when instantiated using this constructor.

Throws:

RuntimeOperationsException - If the String inStr passed in parameter is null

XMLParseException - XML parsing problem while parsing the input String

MBeanException - Wraps a distributed communication Exception.

DescriptorSupport

public DescriptorSupport(String[] fieldNames,
                         Object[] fieldValues)
                  throws RuntimeOperationsException

Constructor taking field names and field values. Neither array can be null.

Parameters:

fieldNames - String array of field names. No elements of this array can be null.

fieldValues - Object array of the corresponding field values. Elements of the array can be null. The fieldValue must be valid for the fieldName (as defined in method isValid)

Note: array sizes of parameters should match. If both arrays are empty, then an empty descriptor is created.

Throws:

RuntimeOperationsException - for illegal value for field Names or field Values. The array lengths must be equal. If the descriptor construction fails for any reason, this exception will be thrown.

DescriptorSupport

public DescriptorSupport(String... fields)

Constructor taking fields in the fieldName=fieldValue format.

Parameters:

fields - String array with each element containing a field name and value. If this array is null or empty, then the default constructor will be executed. Null strings or empty strings will be ignored.

All field values should be Strings. If the field values are not Strings, the programmer will have to reset or convert these fields correctly.

Note: Each string should be of the form fieldName=fieldValue. The field name ends at the first = character; for example if the String is a=b=c then the field name is a and its value is b=c.

Throws:

RuntimeOperationsException - for illegal value for field Names or field Values. The field must contain an "=". "=fieldValue", "fieldName", and "fieldValue" are illegal. FieldName cannot be null. "fieldName=" will cause the value to be null. If the descriptor construction fails for any reason, this exception will be thrown.

Method Detail

getFieldValue

public Object getFieldValue(String fieldName)
                     throws RuntimeOperationsException

Description copied from interface: Descriptor

Returns the value for a specific field name, or null if no value is present for that name.

Specified by:

getFieldValue in interface Descriptor

Parameters:

fieldName - the field name.

Returns:

the corresponding value, or null if the field is not present.

Throws:

RuntimeOperationsException - if the field name is illegal.

setField

public void setField(String fieldName,
                     Object fieldValue)
              throws RuntimeOperationsException

Description copied from interface: Descriptor

Sets the value for a specific field name. This will modify an existing field or add a new field.

The field value will be validated before it is set. If it is not valid, then an exception will be thrown. The meaning of validity is dependent on the descriptor implementation.

Specified by:

setField in interface Descriptor

Parameters:

fieldName - The field name to be set. Cannot be null or empty.

fieldValue - The field value to be set for the field name. Can be null if that is a valid value for the field.

Throws:

RuntimeOperationsException - if the field name or field value is illegal (wrapped exception is IllegalArgumentException); or if the descriptor is immutable (wrapped exception is UnsupportedOperationException).

getFields

public String[] getFields()

Description copied from interface: Descriptor

Returns all of the fields contained in this descriptor as a string array.

Specified by:

getFields in interface Descriptor

Returns:

String array of fields in the format fieldName=fieldValue
If the value of a field is not a String, then the toString() method will be called on it and the returned value, enclosed in parentheses, used as the value for the field in the returned array. If the value of a field is null, then the value of the field in the returned array will be empty. If the descriptor is empty, you will get an empty array.

See Also:

Descriptor.setFields(java.lang.String[], java.lang.Object[])

getFieldNames

public String[] getFieldNames()

Description copied from interface: