org.apache.avalon.framework.parameters
public class Parameters extends Object implements Serializable
Parameters
class represents a set of key-value
pairs.
The Parameters
object provides a mechanism to obtain
values based on a String
name. There are convenience
methods that allow you to use defaults if the value does not exist,
as well as obtain the value in any of the same formats that are in
the Configuration interface.
While there are similarities between the Parameters
object and the java.util.Properties object, there are some
important semantic differences. First, Parameters
are
read-only. Second, Parameters
are easily
derived from Configuration objects. Lastly, the
Parameters
object is derived from XML fragments that
look like this:
<parameter name="param-name" value="param-value" />
Note: this class is not thread safe by default. If you require thread safety please synchronize write access to this class to prevent potential data corruption.
Version: $Id: Parameters.java 30977 2004-07-30 03:57:54 -0500 (Fri, 30 Jul 2004) niclas $
Field Summary | |
---|---|
static Parameters | EMPTY_PARAMETERS
Empty Parameters object
|
Map | m_parameters Static initializer to initialize the empty Parameters object |
boolean | m_readOnly |
Method Summary | |
---|---|
protected void | checkWriteable()
Checks is this Parameters object is writeable.
|
boolean | equals(Object other)
Compare this parameters instance with the supplied object for equality.
|
static Parameters | fromConfiguration(Configuration configuration)
Create a Parameters object from a Configuration
object. |
static Parameters | fromConfiguration(Configuration configuration, String elementName)
Create a Parameters object from a Configuration
object using the supplied element name.
|
static Parameters | fromProperties(Properties properties)
Create a Parameters object from a Properties
object.
|
String[] | getNames()
Retrieve an array of all parameter names.
|
String | getParameter(String name)
Retrieve the String value of the specified parameter.
|
String | getParameter(String name, String defaultValue)
Retrieve the String value of the specified parameter.
|
boolean | getParameterAsBoolean(String name)
Retrieve the boolean value of the specified parameter.
|
boolean | getParameterAsBoolean(String name, boolean defaultValue)
Retrieve the boolean value of the specified parameter.
|
float | getParameterAsFloat(String name)
Retrieve the float value of the specified parameter.
|
float | getParameterAsFloat(String name, float defaultValue)
Retrieve the float value of the specified parameter.
|
int | getParameterAsInteger(String name)
Retrieve the int value of the specified parameter.
|
int | getParameterAsInteger(String name, int defaultValue)
Retrieve the int value of the specified parameter.
|
long | getParameterAsLong(String name)
Retrieve the long value of the specified parameter.
|
long | getParameterAsLong(String name, long defaultValue)
Retrieve the long value of the specified parameter.
|
Iterator | getParameterNames()
Return an Iterator view of all parameter names.
|
int | hashCode()
Returns a hashed value of the Parameters instance.
|
boolean | isParameter(String name)
Test if the specified parameter can be retrieved.
|
void | makeReadOnly()
Make this Parameters read-only so that it will throw a
IllegalStateException if someone tries to
modify it. |
Parameters | merge(Parameters other)
Merge parameters from another Parameters instance
into this.
|
int | parseInt(String value)
Parses string represenation of the int value.
|
long | parseLong(String value)
Parses string represenation of the long value.
|
void | removeParameter(String name)
Remove a parameter from the parameters object |
String | setParameter(String name, String value)
Set the String value of a specified parameter.
|
static Properties | toProperties(Parameters params)
Creates a java.util.Properties object from an Avalon
Parameters object.
|
String | toString() |
Since: 4.1.2
Parameters
object is writeable.
Throws: IllegalStateException if this Parameters
object is read-only
Parameters: other the object to compare this parameters instance with
Returns: true if this parameters instance is equal to the supplied object
Since: 4.3
Parameters
object from a Configuration
object. This acts exactly like the following method call:
Parameters.fromConfiguration(configuration, "parameter");
Parameters: configuration the Configuration
Returns: This Parameters
instance.
Throws: ConfigurationException if an error occurs
Parameters
object from a Configuration
object using the supplied element name.
Parameters: configuration the Configuration elementName the element name for the parameters
Returns: This Parameters
instance.
Throws: ConfigurationException if an error occurs
Since: 4.1
Parameters
object from a Properties
object.
Parameters: properties the Properties
Returns: This Parameters
instance.
Returns: the parameters names
String
value of the specified parameter.
If the specified parameter cannot be found, an exception is thrown.
Parameters: name the name of parameter
Returns: the value of parameter
Throws: ParameterException if the specified parameter cannot be found
String
value of the specified parameter.
If the specified parameter cannot be found, defaultValue
is returned.
Parameters: name the name of parameter defaultValue the default value, returned if parameter does not exist or parameter's name is null
Returns: the value of parameter
boolean
value of the specified parameter.
If the specified parameter cannot be found, an exception is thrown.
Parameters: name the parameter name
Returns: the value
Throws: ParameterException if an error occurs ParameterException
boolean
value of the specified parameter.
If the specified parameter cannot be found, defaultValue
is returned.
Parameters: name the parameter name defaultValue the default value if parameter does not exist or is of wrong type
Returns: the value
float
value of the specified parameter.
If the specified parameter cannot be found, an exception is thrown.
Parameters: name the parameter name
Returns: the value
Throws: ParameterException if the specified parameter cannot be found or is not a Float value
float
value of the specified parameter.
If the specified parameter cannot be found, defaultValue
is returned.
Parameters: name the parameter name defaultValue the default value if parameter does not exist or is of wrong type
Returns: the value
int
value of the specified parameter.
If the specified parameter cannot be found, an exception is thrown.
Hexadecimal numbers begin with 0x, Octal numbers begin with 0o and binary
numbers begin with 0b, all other values are assumed to be decimal.
Parameters: name the name of parameter
Returns: the integer parameter type
Throws: ParameterException if the specified parameter cannot be found or is not an Integer value
int
value of the specified parameter.
If the specified parameter cannot be found, defaultValue
is returned.
Hexadecimal numbers begin with 0x, Octal numbers begin with 0o and binary
numbers begin with 0b, all other values are assumed to be decimal.
Parameters: name the name of parameter defaultValue value returned if parameter does not exist or is of wrong type
Returns: the integer parameter type
long
value of the specified parameter.
If the specified parameter cannot be found, an exception is thrown.
Hexadecimal numbers begin with 0x, Octal numbers begin with 0o and binary
numbers begin with 0b, all other values are assumed to be decimal.
Parameters: name the name of parameter
Returns: the long parameter type
Throws: ParameterException if the specified parameter cannot be found or is not a Long value.
long
value of the specified parameter.
If the specified parameter cannot be found, defaultValue
is returned.
Hexadecimal numbers begin with 0x, Octal numbers begin with 0o and binary
numbers begin with 0b, all other values are assumed to be decimal.
Parameters: name the name of parameter defaultValue value returned if parameter does not exist or is of wrong type
Returns: the long parameter type
Deprecated: Use getNames() instead
Return anIterator
view of all parameter names.
Returns: a iterator of parameter names
Returns: a hashed value of the instance
Since: 4.3
Parameters: name the parameter name
Returns: true if parameter is a name
IllegalStateException
if someone tries to
modify it.Parameters
instance
into this.
Parameters: other the other Parameters
Returns: This Parameters
instance.
int
value.
Hexadecimal numbers begin with 0x, Octal numbers begin with 0o and binary
numbers begin with 0b, all other values are assumed to be decimal.
Parameters: value the value to parse
Returns: the integer value
Throws: NumberFormatException if the specified value can not be parsed
long
value.
Hexadecimal numbers begin with 0x, Octal numbers begin with 0o and binary
numbers begin with 0b, all other values are assumed to be decimal.
Parameters: value the value to parse
Returns: the long value
Throws: NumberFormatException if the specified value can not be parsed
Parameters: name a String
value
Since: 4.1
String
value of a specified parameter.
If the specified value is null the parameter is removed.
Parameters: name a String
value value a String
value
Returns: The previous value of the parameter or null.
Throws: IllegalStateException if the Parameters object is read-only
java.util.Properties
object from an Avalon
Parameters object.
Parameters: params a Parameters
instance
Returns: a Properties
instance