liquibase.resource

Class ClassLoaderResourceAccessor

java.lang.Object

liquibase.AbstractExtensibleObject

liquibase.resource.AbstractResourceAccessor

liquibase.resource.ClassLoaderResourceAccessor

All Implemented Interfaces:

AutoCloseable, Cloneable, ExtensibleObject, ResourceAccessor

Direct Known Subclasses:

CommandLineResourceAccessor, MavenResourceAccessor, OSGiResourceAccessor

public class ClassLoaderResourceAccessor
extends AbstractResourceAccessor
implements AutoCloseable

An implementation of FileSystemResourceAccessor that builds up the file roots based on the passed ClassLoader. If you are using a ClassLoader that isn't based on local files, you will need to use a different ResourceAccessor implementation.

See Also:

for OSGi-based classloaders

Field Summary

Fields

Modifier and Type	Field and Description
protected SortedSet<String>	description
protected List<FileSystem>	rootPaths

Constructor Summary

Constructors

Constructor and Description
ClassLoaderResourceAccessor()
ClassLoaderResourceAccessor(ClassLoader classLoader)

Method Summary

Modifier and Type	Method and Description
void	close()
SortedSet<String>	describeLocations() Returns a description of the places this classloader will look for paths.
protected String	getFinalPath(String relativeTo, String streamPath) Generates a final path to streamPath relative to relatoveTo.
protected void	init() Performs the configuration of this resourceAccessor.
protected boolean	isDirectory(String path) Used by listFromClassLoader(String, boolean, boolean, boolean) to determine if a path is a directory or not.
SortedSet<String>	list(String relativeTo, String path, boolean recursive, boolean includeFiles, boolean includeDirectories) Returns the path to all resources contained in the given path.
protected SortedSet<String>	listFromClassLoader(String path, boolean recursive, boolean includeFiles, boolean includeDirectories) Called by list(String, String, boolean, boolean, boolean) to find files in classLoader.
protected SortedSet<String>	listFromRootPaths(String path, boolean recursive, boolean includeFiles, boolean includeDirectories) Called by list(String, String, boolean, boolean, boolean) to find files in rootPaths.
protected void	loadRootPaths(ClassLoader classLoader) The classloader search logic in list(String, String, boolean, boolean, boolean) does not handle jar files well.
InputStreamList	openStreams(String relativeTo, String streamPath) Return the streams for each resource mapped by the given path.

Methods inherited from class liquibase.resource.AbstractResourceAccessor

openStream

Methods inherited from class liquibase.AbstractExtensibleObject

clone, describe, equals, get, get, get, getAttributes, getFieldValue, getObjectMetaData, getValuePath, has, hashCode, set, toString

Methods inherited from class java.lang.Object

finalize, getClass, notify, notifyAll, wait, wait, wait

Field Detail

rootPaths

protected List<FileSystem> rootPaths

description

protected SortedSet<String> description

Constructor Detail

ClassLoaderResourceAccessor

public ClassLoaderResourceAccessor()

ClassLoaderResourceAccessor

public ClassLoaderResourceAccessor(ClassLoader classLoader)

Method Detail

init

protected void init()

Performs the configuration of this resourceAccessor. Not done in the constructor for performance reasons, but can be called at the beginning of every public method.

loadRootPaths

protected void loadRootPaths(ClassLoader classLoader)

The classloader search logic in list(String, String, boolean, boolean, boolean) does not handle jar files well. This method is called by that method to populate rootPaths with additional paths to search.

openStreams

public InputStreamList openStreams(String relativeTo,
                                   String streamPath)
                            throws IOException

Description copied from interface: ResourceAccessor

Return the streams for each resource mapped by the given path. The path is often a URL but does not have to be. Should accept both / and \ chars for file paths to be platform-independent. If path points to a compressed resource, return a stream of the uncompressed contents of the file. Returns InputStreamList since multiple resources can map to the same path, such as "META-INF/MAINFEST.MF". Remember to close streams when finished with them.

Specified by:

openStreams in interface ResourceAccessor

Parameters:

relativeTo - Location that streamPath should be found relative to. If null, streamPath is an absolute path

Returns:

Empty list if the resource does not exist.

Throws:

IOException - if there is an error reading an existing path.

getFinalPath

protected String getFinalPath(String relativeTo,
                              String streamPath)

Generates a final path to streamPath relative to relatoveTo. If the last part of relativeTo contains a dot character (`.`) this part is considered to be a file name, if it does not, it is considered to be a directory. i.e.

 changelog/some.sql   -> some.sql is considered to be a file
 changelog/some_sql   -> some_sql is considered to be a directory
 

Parameters:

relativeTo - starting point of the path resolution (may be null)

streamPath - a path to a resource relative to relativeTo must not be null

Returns:

a canonicalized absolute path to a resource

list

public SortedSet<String> list(String relativeTo,
                              String path,
                              boolean recursive,
                              boolean includeFiles,
                              boolean includeDirectories)
                       throws IOException

Description copied from interface: ResourceAccessor

Returns the path to all resources contained in the given path. The passed path is not included in the returned set. Returned strings should use "/" for file path separators, regardless of the OS and should accept both / and \ chars for file paths to be platform-independent. Returned set is sorted, normally alphabetically but subclasses can use different comparators. The values returned should be able to be passed into ResourceAccessor.openStreams(String, String) and return the contents. Returned paths should normally be root-relative and therefore not be an absolute path, unless there is a good reason to be absolute.

Specified by:

list in interface ResourceAccessor

Parameters:

relativeTo - Location that streamPath should be found relative to. If null, path is an absolute path

path - The path to lookup resources in.

recursive - Set to true and will return paths to contents in sub directories as well.

includeFiles - Set to true and will return paths to files.

includeDirectories - Set to true and will return paths to directories.

Returns:

empty set if nothing was found

Throws:

IOException - if there is an error reading an existing root.

listFromRootPaths

protected SortedSet<String> listFromRootPaths(String path,
                                              boolean recursive,
                                              boolean includeFiles,
                                              boolean includeDirectories)

Called by list(String, String, boolean, boolean, boolean) to find files in rootPaths.

listFromClassLoader

protected SortedSet<String> listFromClassLoader(String path,
                                                boolean recursive,
                                                boolean includeFiles,
                                                boolean includeDirectories)

Called by list(String, String, boolean, boolean, boolean) to find files in classLoader.

isDirectory

protected boolean isDirectory(String path)

Used by listFromClassLoader(String, boolean, boolean, boolean) to determine if a path is a directory or not.

describeLocations

public SortedSet<String> describeLocations()

Description copied from interface: ResourceAccessor

Returns a description of the places this classloader will look for paths. Used in error messages and other troubleshooting cases.

Specified by:

describeLocations in interface ResourceAccessor

close

public void close()
           throws Exception

Specified by:

close in interface AutoCloseable

Throws:

Exception