org.apache.sling.installer.api

Class InstallableResource

java.lang.Object

org.apache.sling.installer.api.InstallableResource

public class InstallableResource
extends Object

A piece of data that can be installed by the OsgiInstaller Currently the OSGi installer supports bundles and configurations, but it can be extended by additional task factories supporting other formats. The installable resource contains as much information as the client can provide. An input stream or dictionary is mandatory everything else is optional. All optional values will be tried to be evaluated by the OSGi installer. If such evaluation fails the resource will be ignore during installation. If the client provides a configuration it should use the resource type TYPE_PROPERTIES. Otherwise the resource type TYPE_FILE should be used. These two generic types are transformed by resource transformer services to the appropriate resource type like bundle or configuration etc. This frees the client from having any knowledge about the provided data. However, if the client has the knowledge about the data it can provided a specific resource type. The provider should provide a digest for files (input streams). The installer will calculate a digest for dictionaries, regardless if the provider provided a dictionary.

Field Summary

Fields

Modifier and Type	Field and Description
static String	BUNDLE_START_LEVEL Optional parameter in the dictionary if a bundle is installed.
static int	DEFAULT_PRIORITY Default resource priority
static String	INSTALLATION_HINT Optional parameter in the dictionary if a resource (not a dict) is installed.
static String	RESOURCE_IS_TEMPLATE Optional parameter to be passed in the dictionary.
static String	RESOURCE_URI_HINT Optional parameter in the dictionary if a resource (not a dict) is installed.
static String	TYPE_BUNDLE The type for a bundle - in this case getInputStream() must return an input stream to the bundle.
static String	TYPE_CONFIG The type for a configuration - in this case getDictionary() must return a dictionary with the configuration.
static String	TYPE_FILE The type for all other provided data like a bundle etc.
static String	TYPE_PROPERTIES The type for properties - in this case getDictionary() should contain a dictionary or the getInputStream() should point to a property or configuration file.

Constructor Summary

Constructors

Constructor and Description
InstallableResource(String id, InputStream is, Dictionary<String,Object> dict, String digest, String type, Integer priority) Create a data object - this is a simple constructor just using the values as they are provided.

Method Summary

Modifier and Type	Method and Description
Dictionary<String,Object>	getDictionary() Return this resource's dictionary.
String	getDigest() Return this resource's digest.
String	getId() Return this data's id.
InputStream	getInputStream() Return an input stream with the data of this resource.
int	getPriority() Return the priority of this resource.
String	getType() Return the type of this resource.
String	toString()

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Detail

TYPE_PROPERTIES

public static final String TYPE_PROPERTIES

The type for properties - in this case getDictionary() should contain a dictionary or the getInputStream() should point to a property or configuration file.

Since:

3.1

See Also:

Constant Field Values

TYPE_FILE

public static final String TYPE_FILE

The type for all other provided data like a bundle etc. In this case getInputStream() must return an input stream to the data. getDictionary() might return additional information.

Since:

3.1

See Also:

Constant Field Values

TYPE_BUNDLE

public static final String TYPE_BUNDLE

The type for a bundle - in this case getInputStream() must return an input stream to the bundle. getDictionary() might return additional information. This type should only be used if the client really knows that the provided data is a bundle.

See Also:

Constant Field Values

TYPE_CONFIG

public static final String TYPE_CONFIG

The type for a configuration - in this case getDictionary() must return a dictionary with the configuration. This type should only be used if the client really knows that the provided data is an OSGi configuration.

See Also:

Constant Field Values

BUNDLE_START_LEVEL

public static final String BUNDLE_START_LEVEL

Optional parameter in the dictionary if a bundle is installed. If this is set with a valid start level, the bundle is installed in that start level.

See Also:

Constant Field Values

INSTALLATION_HINT

public static final String INSTALLATION_HINT

Optional parameter in the dictionary if a resource (not a dict) is installed. This parameter might be used by the installation task for any purpose like bundle start level etc.

Since:

3.1

See Also:

Constant Field Values

RESOURCE_URI_HINT

public static final String RESOURCE_URI_HINT

Optional parameter in the dictionary if a resource (not a dict) is installed. If this parameter is specified, the installer uses the URI to get the input stream of the resource! Usually the installer copies the resource into the file system and uses this copy. To optimize this, if the URI of the resource is always available (like a file URI), this property can be used to avoid copying the resource. It is only evaluated if the resource type is either unknown (null) or TYPE_FILE and a digest for the resource is delivered. The value of this property is a string. This property might also be set for an UpdateHandler in order to give a hint for the (file) name the resource or dictionary should have.

Since:

3.1.2

See Also:

Constant Field Values

RESOURCE_IS_TEMPLATE

public static final String RESOURCE_IS_TEMPLATE

Optional parameter to be passed in the dictionary. If this property is set (the value is ignored), this artifact acts like a template: If the artifact is changed into a new artifact and later this new artifact is deleted, the installer will not revert to the template. Without this property, the installer would install the original artifact again. For example: if a configuration is installed and then changed through configuration admin, a new artifact for the new configuration is created and managed. If now this configuration is deleted through configuration admin and the original configuration is not marked as a template, the original configuration is applied: the delete through config admin is not a remove of the configuration but a revert to the initial version. If the initial configuration is marked as template with this property, the removal of the changed configuration results in a real removal.

Since:

3.2.0

See Also:

Constant Field Values

DEFAULT_PRIORITY

public static final int DEFAULT_PRIORITY

Default resource priority

See Also:

Constant Field Values

Constructor Detail

InstallableResource

public InstallableResource(String id,
                           InputStream is,
                           Dictionary<String,Object> dict,
                           String digest,
                           String type,
                           Integer priority)

Create a data object - this is a simple constructor just using the values as they are provided.

Parameters:

id - Unique id for the resource, For auto detection of the resource type, the id should contain an extension like .jar, .cfg etc.

is - The input stream to the data or

dict - A dictionary with data

digest - A digest of the data - providers should make sure to set a digest. Calculating a digest by the installer can be very expensive for input streams

type - The resource type if known, otherwise TYPE_PROPERTIES or TYPE_FILE

priority - Optional priority - if not specified DEFAULT_PRIORITY is used

Throws:

IllegalArgumentException - if something is wrong

Method Detail

getId

public String getId()

Return this data's id. It is opaque for the OsgiInstaller but should uniquely identify the resource within the namespace of the used installation mechanism.

Returns:

The id.

getType

public String getType()

Return the type of this resource.

Returns:

The resource type or null if the type is unknown for the client.

getInputStream

public InputStream getInputStream()

Return an input stream with the data of this resource. Null if resource contains a configuration instead. Caller is responsible for closing the stream. If this resource is of type CONFIG it must not return an input stream and if this resource is of type BUNDLE it must return an input stream!

Returns:

The input stream or null.

getDictionary

public Dictionary<String,Object> getDictionary()

Return this resource's dictionary. Null if resource contains an InputStream instead. If this resource is of type CONFIG it must return a dictionary and if this resource is of type BUNDLE it might return a dictionary!

Returns:

The resource's dictionary or null.

getDigest

public String getDigest()

Return this resource's digest. Not necessarily an actual md5 or other digest of the data, can be any string that changes if the data changes.

Returns:

The digest or null

getPriority

public int getPriority()

Return the priority of this resource. Priorities are used to decide which resource to install when several are registered for the same OSGi entity (bundle, config, etc.)

Returns:

The priority.

toString

public String toString()

Overrides:

toString in class Object