org.expath.pkg.repo

Class Storage

java.lang.Object

org.expath.pkg.repo.Storage

Direct Known Subclasses:

ClasspathStorage, FileSystemStorage

public abstract class Storage
extends java.lang.Object

Abstract the physical storage of a repository. For instance, two standard implementations are on disk (the official layout defined in the spec) and within the classpath. The former resolves resource names as filenames on the disk, the later resolves them as resource names within the classpath.

Author:

Florent Georges

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	Storage.NotExistException If a resource or a component does not exist, when trying to resolve a path.
static class	Storage.PackageResolver Resolve paths in a package installed in the repository.

Constructor Summary

Constructors

Constructor and Description
Storage()

Method Summary

Modifier and Type	Method and Description
abstract void	beforeInstall(boolean force, UserInteractionStrategy interact) The opportunity to do anything before the install of a package.
abstract boolean	isReadOnly() Return whether this storage is read-only.
abstract java.util.Set<java.lang.String>	listPackageDirectories() Return the list of installed packages.
abstract Storage.PackageResolver	makePackageResolver(java.lang.String rsrc_name, java.lang.String abbrev) Return a resolver for a specific package.
abstract java.nio.file.Path	makeTempDir(java.lang.String prefix) Create a temporary directory.
abstract boolean	packageKeyExists(java.lang.String key) Each package in a repository can be identified by a unique key.
abstract void	remove(Package pkg) Remove a package.
abstract void	storeInstallDir(java.nio.file.Path dir, java.lang.String key, Package pkg) Actually store the package in the storage.
abstract void	updatePackageLists(Package pkg) The package has just been install, record the information if needed.

Methods inherited from class java.lang.Object

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

Constructor Detail

Storage

public Storage()

Method Detail

isReadOnly

public abstract boolean isReadOnly()

Return whether this storage is read-only.

Returns:

true if read only

makePackageResolver

public abstract Storage.PackageResolver makePackageResolver(java.lang.String rsrc_name,
                                                            java.lang.String abbrev)
                                                     throws PackageException

Return a resolver for a specific package.

Parameters:

rsrc_name - is the name of the resource representing the package. For instance, on the filesystem that is the name of the root directory, and in the classpath that is the name of the root package (in the Java sense).

abbrev - is the abbrev of the package (as in the package descriptor, and must match the module dir within the package).

Returns:

the package resolver

Throws:

PackageException - if an error occurs

listPackageDirectories

public abstract java.util.Set<java.lang.String> listPackageDirectories()
                                                                throws PackageException

Return the list of installed packages. The returned list is the list of the package directories within the repository.

Returns:

the list of installed packages

Throws:

PackageException - if an error occurs

beforeInstall

public abstract void beforeInstall(boolean force,
                                   UserInteractionStrategy interact)
                            throws PackageException

The opportunity to do anything before the install of a package. If installation is not supported (because the storage is read-only), this method must throw an exception.

Parameters:

force - true to force

interact - the user interaction strategy

Throws:

PackageException - if an error occurs

makeTempDir

public abstract java.nio.file.Path makeTempDir(java.lang.String prefix)
                                        throws PackageException

Create a temporary directory.

Parameters:

prefix - prefix for the temporary directory

Returns:

the path to the temporary directory

Throws:

PackageException - if an error occurs

packageKeyExists

public abstract boolean packageKeyExists(java.lang.String key)
                                  throws PackageException

Each package in a repository can be identified by a unique key. The key is computed based on the package abbrev, and is unique. Typically it is used to create a directory or a collection, which requires to have a unique string without '/'.

Parameters:

key - the package key to check for.

Returns:

true of the package key exists.

Throws:

PackageException - if an error occurs

storeInstallDir

public abstract void storeInstallDir(java.nio.file.Path dir,
                                     java.lang.String key,
                                     Package pkg)
                              throws PackageException

Actually store the package in the storage. During install, the package is unzipped in a temporary directory on the file system. This method receives that directory and the package key to use, and actually take control over the temporary directory. It can rename the directory to its final place (does not need to copy it). If it is not using the temporary directory anymore, it must delete it.

Parameters:

dir - the temporary directory where the package was unzipped

key - the package key

pkg - the package descriptor

Throws:

PackageException - if an error occurs

updatePackageLists

public abstract void updatePackageLists(Package pkg)
                                 throws PackageException

The package has just been install, record the information if needed.

Parameters:

pkg - the package descriptor

Throws:

PackageException - if an error occurs

remove

public abstract void remove(Package pkg)
                     throws PackageException

Remove a package.

Parameters:

pkg - the package descriptor.

Throws:

PackageException - if an error occurs