Package org.ros.node.parameter

Interface ParameterTree

All Known Implementing Classes:

AnonymousParmeterTree, DefaultParameterTree

public interface ParameterTree

Provides access to a ParameterServer.

A parameter server is a shared, multi-variate dictionary that is accessible via network APIs. Nodes use this server to store and retrieve parameters at runtime. As it is not designed for high-performance, it is best used for static, non-binary data such as configuration parameters. It is meant to be globally viewable so that tools can easily inspect the configuration state of the system and modify if necessary.

Author:

damonkohler@google.com (Damon Kohler)

See Also:

• Parameter server documentation

Method Summary

Modifier and Type	Method	Description
void	addParameterListener(String name, ParameterListener listener)
void	addParameterListener(GraphName name, ParameterListener listener)	Subscribes to changes to the specified parameter.
void	delete(String name)
void	delete(GraphName name)	Deletes a specified parameter.
boolean	getBoolean(String name)
boolean	getBoolean(String name, boolean defaultValue)
boolean	getBoolean(GraphName name)
boolean	getBoolean(GraphName name, boolean defaultValue)
double	getDouble(String name)
double	getDouble(String name, double defaultValue)
double	getDouble(GraphName name)
double	getDouble(GraphName name, double defaultValue)
int	getInteger(String name)
int	getInteger(String name, int defaultValue)
int	getInteger(GraphName name)
int	getInteger(GraphName name, int defaultValue)
List<?>	getList(String name)
List<?>	getList(String name, List<?> defaultValue)
List<?>	getList(GraphName name)
List<?>	getList(GraphName name, List<?> defaultValue)
Map<?,?>	getMap(String name)
Map<?,?>	getMap(String name, Map<?,?> defaultValue)
Map<?,?>	getMap(GraphName name)
Map<?,?>	getMap(GraphName name, Map<?,?> defaultValue)
Collection<GraphName>	getNames()
String	getString(String name)
String	getString(String name, String defaultValue)
String	getString(GraphName name)
String	getString(GraphName name, String defaultValue)
boolean	has(String name)
boolean	has(GraphName name)
GraphName	search(String name)
GraphName	search(GraphName name)	Search for parameter key on the Parameter Server.
void	set(String name, boolean value)
void	set(String name, double value)
void	set(String name, int value)
void	set(String name, String value)
void	set(String name, List<?> value)
void	set(String name, Map<?,?> value)
void	set(GraphName name, boolean value)
void	set(GraphName name, double value)
void	set(GraphName name, int value)
void	set(GraphName name, String value)
void	set(GraphName name, List<?> value)
void	set(GraphName name, Map<?,?> value)

Method Details

getBoolean

boolean getBoolean(GraphName name)

Parameters:

name - the parameter name

Returns:

the parameter value

Throws:

ParameterNotFoundException - if the parameter is not found

ParameterClassCastException - if the parameter is not the expected type

getBoolean

boolean getBoolean(String name)

See Also:

• getBoolean(GraphName)

getBoolean

boolean getBoolean(GraphName name,
 boolean defaultValue)

Parameters:

name - the parameter name

defaultValue - the default value

Returns:

the parameter value or the default value if the parameter does not exist

Throws:

ParameterClassCastException - if the parameter exists and is not the expected type

getBoolean

boolean getBoolean(String name,
 boolean defaultValue)

See Also:

• getBoolean(GraphName, boolean)

getInteger

int getInteger(GraphName name)

Parameters:

name - the parameter name

Returns:

the parameter value

Throws:

ParameterNotFoundException - if the parameter is not found

ParameterClassCastException - if the parameter is not the expected type

getInteger

int getInteger(String name)

See Also:

• getInteger(GraphName)

getInteger

int getInteger(GraphName name,
 int defaultValue)

Parameters:

name - the parameter name

defaultValue - the default value

Returns:

the parameter value or the default value if the parameter does not exist

Throws:

ParameterClassCastException - if the parameter exists and is not the expected type

getInteger

int getInteger(String name,
 int defaultValue)

See Also:

• getInteger(GraphName, int)

getDouble

double getDouble(GraphName name)

Parameters:

name - the parameter name

Returns:

the parameter value

Throws:

ParameterNotFoundException - if the parameter is not found

ParameterClassCastException - if the parameter is not the expected type

getDouble

double getDouble(String name)

See Also:

• getDouble(GraphName)

getDouble

double getDouble(GraphName name,
 double defaultValue)

Parameters:

name - the parameter name

defaultValue - the default value

Returns:

the parameter value or the default value if the parameter does not exist

Throws:

ParameterClassCastException - if the parameter exists and is not the expected type

getDouble

double getDouble(String name,
 double defaultValue)

See Also:

• getDouble(GraphName, double)

getString

String getString(GraphName name)

Parameters:

name - the parameter name

Returns:

the parameter value:w

Throws:

ParameterNotFoundException - if the parameter is not found

ParameterClassCastException - if the parameter is not the expected type

getString

String getString(String name)

See Also:

• getString(GraphName)

getString

String getString(GraphName name,
 String defaultValue)

Parameters:

name - the parameter name

defaultValue - the default value

Returns:

the parameter value or the default value if the parameter does not exist

Throws:

ParameterClassCastException - if the parameter exists and is not the expected type

getString

String getString(String name,
 String defaultValue)

See Also:

• getString(GraphName, String)

getList

List<?> getList(GraphName name)

Parameters:

name - the parameter name

Returns:

the parameter value

Throws:

ParameterNotFoundException - if the parameter is not found

ParameterClassCastException - if the parameter is not the expected type

getList

List<?> getList(String name)

See Also:

• getList(GraphName)

getList

List<?> getList(GraphName name,
 List<?> defaultValue)

Parameters:

name - the parameter name

defaultValue - the default value

Returns:

the parameter value or the default value if the parameter does not exist

Throws:

ParameterClassCastException - if the parameter exists and is not the expected type

getList

List<?> getList(String name,
 List<?> defaultValue)

See Also:

• getList(GraphName, List)

getMap

Map<?,?> getMap(GraphName name)

Parameters:

name - the parameter name

Returns:

the parameter value

Throws:

ParameterNotFoundException - if the parameter is not found

ParameterClassCastException - if the parameter is not the expected type

getMap

Map<?,?> getMap(String name)

See Also:

• getMap(GraphName)

getMap

Map<?,?> getMap(GraphName name,
 Map<?,?> defaultValue)

Parameters:

name - the parameter name

defaultValue - the default value

Returns:

the parameter value or the default value if the parameter does not exist

Throws:

ParameterClassCastException - if the parameter exists and is not the expected type

getMap

Map<?,?> getMap(String name,
 Map<?,?> defaultValue)

See Also:

• getMap(GraphName, Map)

set

void set(GraphName name,
 boolean value)

Parameters:

name - the parameter name

value - the value that the parameter will be set to

set

void set(String name,
 boolean value)

See Also:

• set(GraphName, boolean)

set

void set(GraphName name,
 int value)

Parameters:

name - the parameter name

value - the value that the parameter will be set to

set

void set(String name,
 int value)

See Also:

• set(GraphName, int)

set

void set(GraphName name,
 double value)

Parameters:

name - the parameter name

value - the value that the parameter will be set to

set

void set(String name,
 double value)

See Also:

• set(GraphName, double)

set

void set(GraphName name,
 String value)

Parameters:

name - the parameter name

value - the value that the parameter will be set to

set

void set(String name,
 String value)

See Also:

• set(GraphName, String)

set

void set(GraphName name,
 List<?> value)

Parameters:

name - the parameter name

value - the value that the parameter will be set to

set

void set(String name,
 List<?> value)

See Also:

• set(GraphName, List)

set

void set(GraphName name,
 Map<?,?> value)

Parameters:

name - the parameter name

value - the value that the parameter will be set to

set

void set(String name,
 Map<?,?> value)

See Also:

• set(GraphName, Map)

has

boolean has(GraphName name)

Parameters:

name - the parameter name

Returns:

true if a parameter with the given name exists, false otherwise

has

boolean has(String name)

See Also:

• has(GraphName)

delete

void delete(GraphName name)

Deletes a specified parameter.

Parameters:

name - the parameter name

delete

void delete(String name)

See Also:

• delete(GraphName)

search

GraphName search(GraphName name)

Search for parameter key on the Parameter Server. Search starts in caller's namespace and proceeds upwards through parent namespaces until the ParameterServer finds a matching key.

Parameters:

name - the parameter name to search for

Returns:

the name of the found parameter or null if no matching parameter was found

search

GraphName search(String name)

See Also:

• search(GraphName)

getNames

Collection<GraphName> getNames()

Returns:

all known parameter names

addParameterListener

void addParameterListener(GraphName name,
 ParameterListener listener)

Subscribes to changes to the specified parameter.

Parameters:

name - the parameter name to subscribe to

listener - a ParameterListener that will be called when the subscribed parameter changes

addParameterListener

void addParameterListener(String name,
 ParameterListener listener)

See Also:

• addParameterListener(GraphName, ParameterListener)