Represents the object name of an MBean, or a pattern that can match the names of several MBeans. Instances of this class are immutable.
An instance of this class can be used to represent:
- An object name
- An object name pattern, within the context of a query
An object name consists of two parts, the domain and the key properties.
The domain is a string of characters not including the character colon (
:). It is recommended that the domain should not contain the string "
//", which is reserved for future use.
If the domain includes at least one occurrence of the wildcard characters asterisk (
*) or question mark (
?), then the object name is a pattern. The asterisk matches any sequence of zero or more characters, while the question mark matches any single character.
If the domain is empty, it will be replaced in certain contexts by the default domain of the MBean server in which the ObjectName is used.
The key properties are an unordered set of keys and associated values.
Each key is a nonempty string of characters which may not contain any of the characters comma (
,), equals (
=), colon, asterisk, or question mark. The same key may not occur twice in a given ObjectName.
Each value associated with a key is a string of characters that is either unquoted or quoted.
An unquoted value is a possibly empty string of characters which may not contain any of the characters comma, equals, colon, or quote.
If the unquoted value contains at least one occurrence of the wildcard characters asterisk or question mark, then the object name is a property value pattern . The asterisk matches any sequence of zero or more characters, while the question mark matches any single character.
A quoted value consists of a quote (
"), followed by a possibly empty string of characters, followed by another quote. Within the string of characters, the backslash (
\) has a special meaning. It must be followed by one of the following characters:
- Another backslash. The second backslash has no special meaning and the two characters represent a single backslash.
- The character 'n'. The two characters represent a newline ('\n' in Java).
- A quote. The two characters represent a quote, and that quote is not considered to terminate the quoted value. An ending closing quote must be present for the quoted value to be valid.
- A question mark (?) or asterisk (*). The two characters represent a question mark or asterisk respectively.
A quote may not appear inside a quoted value except immediately after an odd number of consecutive backslashes.
The quotes surrounding a quoted value, and any backslashes within that value, are considered to be part of the value.
If the quoted value contains at least one occurrence of the characters asterisk or question mark and they are not preceded by a backslash, then they are considered as wildcard characters and the object name is a property value pattern . The asterisk matches any sequence of zero or more characters, while the question mark matches any single character.
An ObjectName may be a property list pattern . In this case it may have zero or more keys and associated values. It matches a nonpattern ObjectName whose domain matches and that contains the same keys and associated values, as well as possibly other keys and values.
An ObjectName is a property value pattern when at least one of its quoted or unquoted key property values contains the wildcard characters asterisk or question mark as described above. In this case it has one or more keys and associated values, with at least one of the values containing wildcard characters. It matches a nonpattern ObjectName whose domain matches and that contains the same keys whose values match; if the property value pattern is also a property list pattern then the nonpattern ObjectName can contain other keys and values.
An ObjectName is a property pattern if it is either a property list pattern or a property value pattern or both.
An ObjectName is a pattern if its domain contains a wildcard or if the ObjectName is a property pattern.
If an ObjectName is not a pattern, it must contain at least one key with its associated value.
Examples of ObjectName patterns are:
*:type=Foo,name=Bar to match names in any domain whose exact set of keys is
d:type=Foo,name=Bar,* to match names in the domain
d that have the keys
type=Foo,name=Bar plus zero or more other keys.
*:type=Foo,name=Bar,* to match names in any domain that has the keys
type=Foo,name=Bar plus zero or more other keys.
d:type=F?o,name=Bar will match e.g.
d:type=F*o,name=Bar will match e.g.
d:type=Foo,name="B*" will match e.g.
d:type=Foo,name="Bling". Wildcards are recognized even inside quotes, and like other special characters can be escaped with
An ObjectName can be written as a String with the following elements in order:
- The domain.
- A colon (
- A key property list as defined below.
A key property list written as a String is a comma-separated list of elements. Each element is either an asterisk or a key property. A key property consists of a key, an equals (
=), and the associated value.
At most one element of a key property list may be an asterisk. If the key property list contains an asterisk element, the ObjectName is a property list pattern.
Spaces have no special significance in a String representing an ObjectName. For example, the String:
domain: key1 = value1 , key2 = value2
represents an ObjectName with two keys. The name of each key contains six characters, of which the first and last are spaces. The value associated with the key
" key1 "
also begins and ends with a space.
In addition to the restrictions on characters spelt out above, no part of an ObjectName may contain a newline character (
'\n'), whether the domain, a key, or a value, whether quoted or unquoted. The newline character can be represented in a quoted value with the sequence
The rules on special characters and quoting apply regardless of which constructor is used to make an ObjectName.
To avoid collisions between MBeans supplied by different vendors, a useful convention is to begin the domain name with the reverse DNS name of the organization that specifies the MBeans, followed by a period and a string whose interpretation is determined by that organization. For example, MBeans specified by
example.com would have domains such as
com.example.MyDomain. This is essentially the same convention as for Java-language package names.
The serialVersionUID of this class is