Location (Apache Karaf :: Main 2.3.0.redhat-611454 API)

All Known Implementing Classes:

BasicLocation
```
public interface Location
```
A Location represents a URL which may have a default value, may be read only, may or may not have a current value and may be cascaded on to a parent location.
This interface is not intended to be implemented by clients.

Since:

3.0

Field Summary

Fields
Modifier and Type	Field and Description
`static String`	`CONFIGURATION_FILTER` Constant which defines the filter string for acquiring the service which specifies the configuration location.
`static String`	`ECLIPSE_HOME_FILTER` Constant which defines the filter string for acquiring the service which specifies the eclipse home location.
`static String`	`INSTALL_FILTER` Constant which defines the filter string for acquiring the service which specifies the install location.
`static String`	`INSTANCE_FILTER` Constant which defines the filter string for acquiring the service which specifies the instance location.
`static String`	`USER_FILTER` Constant which defines the filter string for acquiring the service which specifies the user location.

Method Summary

Methods
Modifier and Type	Method and Description
`boolean`	`allowsDefault()` Returns `true` if this location allows a default value to be assigned and `false` otherwise.
`Location`	`createLocation(Location parent, URL defaultValue, boolean readonly)` Constructs a new location.
`URL`	`getDataArea(String path)` Returns a URL to the specified path within this location.
`URL`	`getDefault()` Returns the default value of this location if any.
`Location`	`getParentLocation()` Returns the parent of this location or `null` if none is available.
`URL`	`getURL()` Returns the actual `URL` of this location.
`boolean`	`isLocked()` Returns `true` if this location is locked and `false` otherwise.
`boolean`	`isReadOnly()` Returns `true` if this location represents a read only location and `false` otherwise.
`boolean`	`isSet()` Returns `true` if this location has a value and `false` otherwise.
`boolean`	`lock()` Attempts to lock this location with a canonical locking mechanism and return `true` if the lock could be acquired.
`void`	`release()` Releases the lock on this location.
`boolean`	`set(URL value, boolean lock)` Sets and optionally locks the location's value to the given `URL`.
`boolean`	`set(URL value, boolean lock, String lockFilePath)` Sets and optionally locks the location's value to the given `URL` using the given lock file.
`boolean`	`setURL(URL value, boolean lock)` Deprecated. use `set(URL, boolean)` instead.

- Field Detail
  - INSTANCE_FILTER
```
static final String INSTANCE_FILTER
```
    Constant which defines the filter string for acquiring the service which specifies the instance location.
    
    Since:
    
    3.2
  - INSTALL_FILTER
```
static final String INSTALL_FILTER
```
    Constant which defines the filter string for acquiring the service which specifies the install location.
    
    Since:
    
    3.2
  - CONFIGURATION_FILTER
```
static final String CONFIGURATION_FILTER
```
    Constant which defines the filter string for acquiring the service which specifies the configuration location.
    
    Since:
    
    3.2
  - USER_FILTER
```
static final String USER_FILTER
```
    Constant which defines the filter string for acquiring the service which specifies the user location.
    
    Since:
    
    3.2
  - ECLIPSE_HOME_FILTER
```
static final String ECLIPSE_HOME_FILTER
```
    Constant which defines the filter string for acquiring the service which specifies the eclipse home location.
    
    Since:
    
    3.4
- Method Detail
  - allowsDefault
```
boolean allowsDefault()
```
    Returns true if this location allows a default value to be assigned and false otherwise.
    
    Returns:
    whether or not this location can have a default value assigned
  - getDefault
```
URL getDefault()
```
    Returns the default value of this location if any. If no default is available then null is returned. Note that even locations which allow defaults may still return null.
    
    Returns:
    the default value for this location or null
  - getParentLocation
```
Location getParentLocation()
```
    Returns the parent of this location or null if none is available.
    
    Returns:
    the parent of this location or null
  - getURL
```
URL getURL()
```
    Returns the actual URL of this location. If the location's value has been set, that value is returned. If the value is not set and the location allows defaults, the value is set to the default and returned. In all other cases null is returned.
    
    Returns:
    the URL for this location or null if none
  - isSet
```
boolean isSet()
```
    Returns true if this location has a value and false otherwise.
    
    Returns:
    boolean value indicating whether or not the value is set
  - isReadOnly
```
boolean isReadOnly()
```
    Returns true if this location represents a read only location and false otherwise. The read only character of a location is not in enforced in any way but rather expresses the intention of the location's creator.
    
    Returns:
    boolean value indicating whether the location is read only
  - setURL
```
boolean setURL(URL value,
             boolean lock)
               throws IllegalStateException
```
    Deprecated. use set(URL, boolean) instead.
    
    Sets and optionally locks the location's value to the given URL. If the location already has a value an exception is thrown. If locking is requested and fails, false is returned and the URL of this location is not set.
    
    Parameters:
    value - the value of this location
    lock - whether or not to lock this location
    
    Returns:
    whether or not the location was successfully set and, if requested, locked.
    
    Throws:
    
    IllegalStateException - if the location's value is already set
  - set
```
boolean set(URL value,
          boolean lock)
            throws IllegalStateException,
                   IOException
```
    Sets and optionally locks the location's value to the given URL. If the location already has a value an exception is thrown. If locking is requested and fails, false is returned and the URL of this location is not set.
    
    Parameters:
    value - the value of this location
    lock - whether or not to lock this location
    
    Returns:
    whether or not the location was successfully set and, if requested, locked.
    
    Throws:
    
    IllegalStateException - if the location's value is already set
    
    IOException - if there was an unexpected problem while acquiring the lock
    Since:
    
    3.4
  - set
```
boolean set(URL value,
          boolean lock,
          String lockFilePath)
            throws IllegalStateException,
                   IOException
```
    Sets and optionally locks the location's value to the given URL using the given lock file. If the location already has a value an exception is thrown. If locking is requested and fails, false is returned and the URL of this location is not set.
    
    Parameters:
    value - the value of this location
    lock - whether or not to lock this location
    lockFilePath - the path to the lock file. This path will be used to establish locks on this location. The path may be an absolute path or it may be relative to the given URL. If a null value is used then a default lock path will be used for this location.
    
    Returns:
    whether or not the location was successfully set and, if requested, locked.
    
    Throws:
    
    IllegalStateException - if the location's value is already set
    
    IOException - if there was an unexpected problem while acquiring the lock
    Since:
    
    3.5
  - lock
```
boolean lock()
             throws IOException
```
    Attempts to lock this location with a canonical locking mechanism and return true if the lock could be acquired. Not all locations can be locked.
    Locking a location is advisory only. That is, it does not prevent other applications from modifying the same location
    
    Returns:
    true if the lock could be acquired; otherwise false is returned
    
    Throws:
    
    IOException - if there was an unexpected problem while acquiring the lock
  - release
```
void release()
```
    Releases the lock on this location. If the location is not already locked, no action is taken.
  - isLocked
```
boolean isLocked()
                 throws IOException
```
    Returns true if this location is locked and false otherwise.
    
    Returns:
    boolean value indicating whether or not this location is locked
    
    Throws:
    
    IOException - if there was an unexpected problem reading the lock
    Since:
    
    3.4
  - createLocation
```
Location createLocation(Location parent,
                      URL defaultValue,
                      boolean readonly)
```
    Constructs a new location.
    
    Parameters:
    parent - the parent location. A null value is allowed.
    defaultValue - the default value of the location. A null value is allowed.
    readonly - true if the location is read-only.
    
    Returns:
    a new location.
    Since:
    
    3.4
  - getDataArea
```
URL getDataArea(String path)
                throws IOException
```
    Returns a URL to the specified path within this location. The path of the returned URL may not exist yet. It is the responsibility of the client to create the content of the data area returned if it does not exist.
    This method can be used to obtain a private area within the given location. For example use the symbolic name of a bundle to obtain a data area specific to that bundle.
    
    Clients should check if the location is read only before writing anything to the returned data area. An IOException will be thrown if this method is called and the location URL has not been set and there is no default value for this location.
    
    Parameters:
    path - the name of the path to get from this location
    
    Returns:
    the URL to the data area with the specified path.
    
    Throws:
    
    IOException - if the location URL is not already set
    Since:
    
    3.6

Interface Location

Field Summary

Method Summary

Field Detail

INSTANCE_FILTER

INSTALL_FILTER

CONFIGURATION_FILTER

USER_FILTER

ECLIPSE_HOME_FILTER

Method Detail

allowsDefault

getDefault

getParentLocation

getURL

isSet

isReadOnly

setURL

set

set

lock

release

isLocked

createLocation

getDataArea