PkgAgentSystem
Class ResourcePackage

java.lang.Object
  |
  +--PkgAgentSystem.ResourcePackage

class ResourcePackage

extends Object

Used to find resources on a searchpath. Each classloader (and therefore each agent) has its own resource package.
The searchpath consists of a number of files or directories separated by a semicolon. Files must be either directly a resource or a jar- or zip-file (which will be searched). Directories are searched for the resource directly (if the resource is contained in a package, all '.' are replaced by '/' or '\' to reach the correct subdirectory). Also in directories all contained zip- and jar-files are searched for the resource.

Version:

1.0, 1.7.2000

Author:

Michael Sonntag

See Also:

AgentClassLoader

Field Summary

protected String

codeOrigin From where the code is loaded.

Constructor Summary

ResourcePackage(AgentData data)
Creates a new resource package for a certain agent.

Method Summary

protected void	EnumerateJarFile(Hashtable res, String file, String name) Searches a JAR-file for all resource with a specific name.
CertificateWrapper[]	getCodeCertificates() Returns all code certificates which were used to sign this package.
protected URL	getFromPackedFile(String file, String name) Searches a JAR- or ZIP-file for a specific resource and loads it.
Manifest	getManifest() Returns the manifest for this code package.
byte[]	getManifestSource() Returns the original bytes of the manifest for this code package.
String	getPackage() Returns the name of a file, where the code for this resource package can be found.
Enumeration	getResources(String name) Returns an enumeration of all LOCAL resource with this name from the codeOrigin of this object.
URL	getResourceURL(String name) Returns an URL to the resource with the provided name.
protected String	getSearchPath() Returns the complete searchpath.

Methods inherited from class java.lang.Object

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

Field Detail

codeOrigin

protected String codeOrigin

From where the code is loaded. Duplicate of data.codeOrigin

Constructor Detail

ResourcePackage

public ResourcePackage(AgentData data)

Creates a new resource package for a certain agent.

Parameters:

data - the management data of the agent for which to load classes

Method Detail

getSearchPath

protected String getSearchPath()

Returns the complete searchpath. Searching will be done from the front to the back, so previous entries will be used if a resource with the same name appears again behind.
Construction: Classpath ; library path of the agent system ; and either the code origin (directory or file) or, if this is not set, the agent classpath (from where agents are loaded)

Returns:

string of directories and files separated by ';'

getResourceURL

public URL getResourceURL(String name)

Returns an URL to the resource with the provided name. Searches only the searchpath.

Returns:

an URL to the resource

See Also:

getSearchPath(), URL.openStream(), URL.openConnection(), URLConnection

getResources

public Enumeration getResources(String name)

Returns an enumeration of all LOCAL resource with this name from the codeOrigin of this object. When Searching for test.gif, 'img/test.gif' will be included, but not 'mytest.gif'.

Parameters:

name - the name of the resources

Returns:

an enumeration of all resources with this name

getManifest

public Manifest getManifest()

Returns the manifest for this code package.

Returns:

the manifest or null if not contained or not applicable (zip, directory)

getManifestSource

public byte[] getManifestSource()

Returns the original bytes of the manifest for this code package.

Returns:

the manifest bytes or null if not contained or not applicable (zip, directory)

getCodeCertificates

public CertificateWrapper[] getCodeCertificates()

Returns all code certificates which were used to sign this package. Only those will be returned, where the verification was always successful and which were used for signing ALL files in the package.

Returns:

array or certificates (not ordered)

getPackage

public String getPackage()

Returns the name of a file, where the code for this resource package can be found. If the source is not a jar or zip-file itself but a directory, the content of this directory (including subdirectories) is packed into a temporary file and the name of this file returned.

Returns:

name of the file with the complete code (and possibly other resources) for this resource package

getFromPackedFile

protected URL getFromPackedFile(String file,
                                String name)

Searches a JAR- or ZIP-file for a specific resource and loads it. Any errors will be ignored: The resource will not be created then. When Searching for test.gif, 'img/test.gif' will be included but not 'mytest.gif'.

Parameters:

file - filename to search (must be a JAR- or ZIP-file; will not be checked)

name - the name of the resource to find

EnumerateJarFile

protected void EnumerateJarFile(Hashtable res,
                                String file,
                                String name)

Searches a JAR-file for all resource with a specific name. Any errors will be ignored: The resource will not be listed. When Searching for test.gif, 'img/test.gif' will be included but not 'mytest.gif'.

Parameters:

res - Hashtable where the found resource will be stored (URL with URL as key)

file - filename to search (must be a JAR-file; will not be checked)

name - the name of the resource to find