com.opensymphony.xwork2.util.finder

Class ResourceFinder

java.lang.Object

com.opensymphony.xwork2.util.finder.ResourceFinder

public class ResourceFinder
extends Object

Author:

David Blevins

Constructor Summary

Constructors

Constructor and Description
ResourceFinder(String path)
ResourceFinder(String path, ClassLoaderInterface classLoaderInterface)
ResourceFinder(String path, ClassLoaderInterface classLoaderInterface, URL... urls)
ResourceFinder(String path, URL... urls)
ResourceFinder(URL... urls)

Method Summary

Modifier and Type	Method and Description
URL	find(String uri)
List<URL>	findAll(String uri)
List<Class>	findAllClasses(String uri) Executes findAllStrings assuming the strings are the names of a classes that should be loaded and returned.
List<Class>	findAllImplementations(Class interfase) Assumes the class specified points to a file in the classpath that contains the name of a class that implements or is a subclass of the specfied class.
List<Properties>	findAllProperties(String uri) Finds the corresponding resources and reads them in as a properties files
List<String>	findAllStrings(String uri) Reads the contents of the found URLs as a list of String's and returns them.
List<Class>	findAvailableClasses(String uri) Executes findAvailableStrings assuming the strings are the names of a classes that should be loaded and returned.
List<Class>	findAvailableImplementations(Class interfase) Assumes the class specified points to a file in the classpath that contains the name of a class that implements or is a subclass of the specfied class.
List<Properties>	findAvailableProperties(String uri) Finds the corresponding resources and reads them in as a properties files
List<String>	findAvailableStrings(String uri) Reads the contents of the found URLs as a Strings and returns them.
Class	findClass(String uri) Executes findString(String) assuming the contents URL found is the name of a class that should be loaded and returned.
Class	findImplementation(Class interfase) Assumes the class specified points to a file in the classpath that contains the name of a class that implements or is a subclass of the specfied class.
Set<String>	findPackages(String uri)
Map<URL,Set<String>>	findPackagesMap(String uri)
Properties	findProperties(String uri) Finds the corresponding resource and reads it in as a properties file
String	findString(String uri) Reads the contents of the URL as a String's and returns it.
Map<String,URL>	getResourcesMap(String uri)
List<String>	getResourcesNotLoaded() Returns a list of resources that could not be loaded in the last invoked findAvailable* or mapAvailable* methods.
Map<String,Class>	mapAllClasses(String uri) Executes mapAllStrings assuming the value of each entry in the map is the name of a class that should be loaded.
Map<String,Class>	mapAllImplementations(Class interfase) Assumes the class specified points to a directory in the classpath that holds files containing the name of a class that implements or is a subclass of the specified class.
Map<String,Properties>	mapAllProperties(String uri) Finds the corresponding resources and reads them in as a properties files
Map<String,String>	mapAllStrings(String uri) Reads the contents of all non-directory URLs immediately under the specified location and returns them in a map keyed by the file name.
Map<String,Class>	mapAvailableClasses(String uri) Executes mapAvailableStrings assuming the value of each entry in the map is the name of a class that should be loaded.
Map<String,Class>	mapAvailableImplementations(Class interfase) Assumes the class specified points to a directory in the classpath that holds files containing the name of a class that implements or is a subclass of the specified class.
Map<String,Properties>	mapAvailableProperties(String uri) Finds the corresponding resources and reads them in as a properties files
Map<String,String>	mapAvailableStrings(String uri) Reads the contents of all non-directory URLs immediately under the specified location and returns them in a map keyed by the file name.

Methods inherited from class java.lang.Object

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

Constructor Detail

ResourceFinder

public ResourceFinder(URL... urls)

ResourceFinder

public ResourceFinder(String path)

ResourceFinder

public ResourceFinder(String path,
                      URL... urls)

ResourceFinder

public ResourceFinder(String path,
                      ClassLoaderInterface classLoaderInterface)

ResourceFinder

public ResourceFinder(String path,
                      ClassLoaderInterface classLoaderInterface,
                      URL... urls)

Method Detail

getResourcesNotLoaded

public List<String> getResourcesNotLoaded()

Returns a list of resources that could not be loaded in the last invoked findAvailable* or mapAvailable* methods.

The list will only contain entries of resources that match the requirements of the last invoked findAvailable* or mapAvailable* methods, but were unable to be loaded and included in their results.

The list returned is unmodifiable and the results of this method will change after each invocation of a findAvailable* or mapAvailable* methods.

This method is not thread safe.

Returns:

not loaded resources

find

public URL find(String uri)
         throws IOException

Throws:

IOException

findAll

public List<URL> findAll(String uri)
                  throws IOException

Throws:

IOException

findString

public String findString(String uri)
                  throws IOException

Reads the contents of the URL as a String's and returns it.

Parameters:

uri - URL

Returns:

a stringified content of a resource

Throws:

IOException - if a resource pointed out by the uri param could not be find

See Also:

ClassLoader.getResource(String)

findAllStrings

public List<String> findAllStrings(String uri)
                            throws IOException

Reads the contents of the found URLs as a list of String's and returns them.

Parameters:

uri - URL

Returns:

a list of the content of each resource URL found

Throws:

IOException - if any of the found URLs are unable to be read.

findAvailableStrings

public List<String> findAvailableStrings(String uri)
                                  throws IOException

Reads the contents of the found URLs as a Strings and returns them. Individual URLs that cannot be read are skipped and added to the list of 'resourcesNotLoaded'

Parameters:

uri - URL

Returns:

a list of the content of each resource URL found

Throws:

IOException - if classLoader.getResources throws an exception

mapAllStrings

public Map<String,String> mapAllStrings(String uri)
                                 throws IOException

Reads the contents of all non-directory URLs immediately under the specified location and returns them in a map keyed by the file name.

Any URLs that cannot be read will cause an exception to be thrown.

Example classpath:

 META-INF/serializables/one
 META-INF/serializables/two
 META-INF/serializables/three
 META-INF/serializables/four/foo.txt
 

 ResourceFinder finder = new ResourceFinder("META-INF/");
 Map map = finder.mapAvailableStrings("serializables");
 map.contains("one");  // true
 map.contains("two");  // true
 map.contains("three");  // true
 map.contains("four");  // false
 

Parameters:

uri - URL

Returns:

a list of the content of each resource URL found

Throws:

IOException - if any of the urls cannot be read

mapAvailableStrings

public Map<String,String> mapAvailableStrings(String uri)
                                       throws IOException

Reads the contents of all non-directory URLs immediately under the specified location and returns them in a map keyed by the file name.

Individual URLs that cannot be read are skipped and added to the list of 'resourcesNotLoaded'

Example classpath:

 META-INF/serializables/one
 META-INF/serializables/two      # not readable
 META-INF/serializables/three
 META-INF/serializables/four/foo.txt
 

 ResourceFinder finder = new ResourceFinder("META-INF/");
 Map map = finder.mapAvailableStrings("serializables");
 map.contains("one");  // true
 map.contains("two");  // false
 map.contains("three");  // true
 map.contains("four");  // false
 

Parameters:

uri - URL

Returns:

a list of the content of each resource URL found

Throws:

IOException - if classLoader.getResources throws an exception

findClass

public Class findClass(String uri)
                throws IOException,
                       ClassNotFoundException

Executes findString(String) assuming the contents URL found is the name of a class that should be loaded and returned.

Parameters:

uri - URL

Returns:

class that should be loaded

Throws:

IOException - in case of IO errors

ClassNotFoundException - when class is not found

findAllClasses

public List<Class> findAllClasses(String uri)
                           throws IOException,
                                  ClassNotFoundException

Executes findAllStrings assuming the strings are the names of a classes that should be loaded and returned.

Any URL or class that cannot be loaded will cause an exception to be thrown.

Parameters:

uri - URL

Returns:

classes that should be loaded

Throws:

IOException - in case of IO errors

ClassNotFoundException - when class is not found

findAvailableClasses

public List<Class> findAvailableClasses(String uri)
                                 throws IOException

Executes findAvailableStrings assuming the strings are the names of a classes that should be loaded and returned.

Any class that cannot be loaded will be skipped and placed in the 'resourcesNotLoaded' collection.

Parameters:

uri - URL

Returns:

list of available classes

Throws:

IOException - if classLoader.getResources throws an exception

mapAllClasses

public Map<String,Class> mapAllClasses(String uri)
                                throws IOException,
                                       ClassNotFoundException

Executes mapAllStrings assuming the value of each entry in the map is the name of a class that should be loaded.

Any class that cannot be loaded will be cause an exception to be thrown.

Example classpath:

 META-INF/xmlparsers/xerces
 META-INF/xmlparsers/crimson
 

 ResourceFinder finder = new ResourceFinder("META-INF/");
 Map map = finder.mapAvailableStrings("xmlparsers");
 map.contains("xerces");  // true
 map.contains("crimson");  // true
 Class xercesClass = map.get("xerces");
 Class crimsonClass = map.get("crimson");
 

Parameters:

uri - URL

Returns:

map of all classes

Throws:

IOException - in case of IO errors

ClassNotFoundException - when class is not found

mapAvailableClasses

public Map<String,Class> mapAvailableClasses(String uri)
                                      throws IOException

Executes mapAvailableStrings assuming the value of each entry in the map is the name of a class that should be loaded.

Any class that cannot be loaded will be skipped and placed in the 'resourcesNotLoaded' collection.

Example classpath:

 META-INF/xmlparsers/xerces
 META-INF/xmlparsers/crimson
 

 ResourceFinder finder = new ResourceFinder("META-INF/");
 Map map = finder.mapAvailableStrings("xmlparsers");
 map.contains("xerces");  // true
 map.contains("crimson");  // true
 Class xercesClass = map.get("xerces");
 Class crimsonClass = map.get("crimson");
 

Parameters:

uri - URL

Returns:

map of available classes

Throws:

IOException - if classLoader.getResources throws an exception

findImplementation

public Class findImplementation(Class interfase)
                         throws IOException,
                                ClassNotFoundException

Assumes the class specified points to a file in the classpath that contains the name of a class that implements or is a subclass of the specfied class.

Any class that cannot be loaded will be cause an exception to be thrown.

Example classpath:

 META-INF/java.io.InputStream    # contains the classname org.acme.AcmeInputStream
 META-INF/java.io.OutputStream
 

 ResourceFinder finder = new ResourceFinder("META-INF/");
 Class clazz = finder.findImplementation(java.io.InputStream.class);
 clazz.getName();  // returns "org.acme.AcmeInputStream"
 

Parameters:

interfase - a superclass or interface

Returns:

implementation class

Throws:

IOException - if the URL cannot be read

ClassNotFoundException - if the class found is not loadable

ClassCastException - if the class found is not assignable to the specified superclass or interface

findAllImplementations

public List<Class> findAllImplementations(Class interfase)
                                   throws IOException,
                                          ClassNotFoundException

Assumes the class specified points to a file in the classpath that contains the name of a class that implements or is a subclass of the specfied class.

Any class that cannot be loaded or assigned to the specified interface will be cause an exception to be thrown.

Example classpath:

 META-INF/java.io.InputStream    # contains the classname org.acme.AcmeInputStream
 META-INF/java.io.InputStream    # contains the classname org.widget.NeatoInputStream
 META-INF/java.io.InputStream    # contains the classname com.foo.BarInputStream
 

 ResourceFinder finder = new ResourceFinder("META-INF/");
 List classes = finder.findAllImplementations(java.io.InputStream.class);
 classes.contains("org.acme.AcmeInputStream");  // true
 classes.contains("org.widget.NeatoInputStream");  // true
 classes.contains("com.foo.BarInputStream");  // true
 

Parameters:

interfase - a superclass or interface

Returns:

list of implementation classes

Throws:

IOException - if the URL cannot be read

ClassNotFoundException - if the class found is not loadable

ClassCastException - if the class found is not assignable to the specified superclass or interface

findAvailableImplementations

public List<Class> findAvailableImplementations(Class interfase)
                                         throws IOException

Assumes the class specified points to a file in the classpath that contains the name of a class that implements or is a subclass of the specfied class.

Any class that cannot be loaded or are not assignable to the specified class will be skipped and placed in the 'resourcesNotLoaded' collection.

Example classpath:

 META-INF/java.io.InputStream    # contains the classname org.acme.AcmeInputStream
 META-INF/java.io.InputStream    # contains the classname org.widget.NeatoInputStream
 META-INF/java.io.InputStream    # contains the classname com.foo.BarInputStream
 

 ResourceFinder finder = new ResourceFinder("META-INF/");
 List classes = finder.findAllImplementations(java.io.InputStream.class);
 classes.contains("org.acme.AcmeInputStream");  // true
 classes.contains("org.widget.NeatoInputStream");  // true
 classes.contains("com.foo.BarInputStream");  // true
 

Parameters:

interfase - a superclass or interface

Returns:

list of implementation classes

Throws:

IOException - if classLoader.getResources throws an exception

mapAllImplementations

public Map<String,Class> mapAllImplementations(Class interfase)
                                        throws IOException,
                                               ClassNotFoundException

Assumes the class specified points to a directory in the classpath that holds files containing the name of a class that implements or is a subclass of the specified class.

Any class that cannot be loaded or assigned to the specified interface will be cause an exception to be thrown.

Example classpath:

 META-INF/java.net.URLStreamHandler/jar
 META-INF/java.net.URLStreamHandler/file
 META-INF/java.net.URLStreamHandler/http
 

 ResourceFinder finder = new ResourceFinder("META-INF/");
 Map map = finder.mapAllImplementations(java.net.URLStreamHandler.class);
 Class jarUrlHandler = map.get("jar");
 Class fileUrlHandler = map.get("file");
 Class httpUrlHandler = map.get("http");
 

Parameters:

interfase - a superclass or interface

Returns:

map of implementation classes

Throws:

IOException - if the URL cannot be read

ClassNotFoundException - if the class found is not loadable

ClassCastException - if the class found is not assignable to the specified superclass or interface

mapAvailableImplementations

public Map<String,Class> mapAvailableImplementations(Class interfase)
                                              throws IOException

Assumes the class specified points to a directory in the classpath that holds files containing the name of a class that implements or is a subclass of the specified class.

Any class that cannot be loaded or are not assignable to the specified class will be skipped and placed in the 'resourcesNotLoaded' collection.

Example classpath:

 META-INF/java.net.URLStreamHandler/jar
 META-INF/java.net.URLStreamHandler/file
 META-INF/java.net.URLStreamHandler/http
 

 ResourceFinder finder = new ResourceFinder("META-INF/");
 Map map = finder.mapAllImplementations(java.net.URLStreamHandler.class);
 Class jarUrlHandler = map.get("jar");
 Class fileUrlHandler = map.get("file");
 Class httpUrlHandler = map.get("http");
 

Parameters:

interfase - a superclass or interface

Returns:

list of available implementation classes

Throws:

IOException - if classLoader.getResources throws an exception

findProperties

public Properties findProperties(String uri)
                          throws IOException

Finds the corresponding resource and reads it in as a properties file

Example classpath:

 META-INF/widget.properties
 

 ResourceFinder finder = new ResourceFinder("META-INF/");
 Properties widgetProps = finder.findProperties("widget.properties");
 

Parameters:

uri - URL

Returns:

corresponding resource as properties

Throws:

IOException - if the URL cannot be read or is not in properties file format

findAllProperties

public List<Properties> findAllProperties(String uri)
                                   throws IOException

Finds the corresponding resources and reads them in as a properties files

Any URL that cannot be read in as a properties file will cause an exception to be thrown.

Example classpath:

 META-INF/app.properties
 META-INF/app.properties
 META-INF/app.properties
 

 ResourceFinder finder = new ResourceFinder("META-INF/");
 List<Properties> appProps = finder.findAllProperties("app.properties");
 

Parameters:

uri - URL

Returns:

corresponding resource as list of properties

Throws:

IOException - if the URL cannot be read or is not in properties file format

findAvailableProperties

public List<Properties> findAvailableProperties(String uri)
                                         throws IOException

Finds the corresponding resources and reads them in as a properties files

Any URL that cannot be read in as a properties file will be added to the 'resourcesNotLoaded' collection.

Example classpath:

 META-INF/app.properties
 META-INF/app.properties
 META-INF/app.properties
 

 ResourceFinder finder = new ResourceFinder("META-INF/");
 List<Properties> appProps = finder.findAvailableProperties("app.properties");
 

Parameters:

uri - URL

Returns:

corresponding resource as list of properties

Throws:

IOException - if classLoader.getResources throws an exception

mapAllProperties

public Map<String,Properties> mapAllProperties(String uri)
                                        throws IOException

Finds the corresponding resources and reads them in as a properties files

Any URL that cannot be read in as a properties file will cause an exception to be thrown.

Example classpath:

 META-INF/jdbcDrivers/oracle.properties
 META-INF/jdbcDrivers/mysql.props
 META-INF/jdbcDrivers/derby
 

 ResourceFinder finder = new ResourceFinder("META-INF/");
 List<Properties> driversList = finder.findAvailableProperties("jdbcDrivers");
 Properties oracleProps = driversList.get("oracle.properties");
 Properties mysqlProps = driversList.get("mysql.props");
 Properties derbyProps = driversList.get("derby");
 

Parameters:

uri - URL

Returns:

corresponding resource as map of properties

Throws:

IOException - if the URL cannot be read or is not in properties file format

mapAvailableProperties

public Map<String,Properties> mapAvailableProperties(String uri)
                                              throws IOException

Finds the corresponding resources and reads them in as a properties files

Any URL that cannot be read in as a properties file will be added to the 'resourcesNotLoaded' collection.

Example classpath:

 META-INF/jdbcDrivers/oracle.properties
 META-INF/jdbcDrivers/mysql.props
 META-INF/jdbcDrivers/derby
 

 ResourceFinder finder = new ResourceFinder("META-INF/");
 List<Properties> driversList = finder.findAvailableProperties("jdbcDrivers");
 Properties oracleProps = driversList.get("oracle.properties");
 Properties mysqlProps = driversList.get("mysql.props");
 Properties derbyProps = driversList.get("derby");
 

Parameters:

uri - URL

Returns:

corresponding resource as map of available properties

Throws:

IOException - if classLoader.getResources throws an exception

getResourcesMap

public Map<String,URL> getResourcesMap(String uri)
                                throws IOException

Throws:

IOException

findPackages

public Set<String> findPackages(String uri)
                         throws IOException

Parameters:

uri - URL

Returns:

set of subpackages from jars or dirs

Throws:

IOException - in case of IO errors

findPackagesMap

public Map<URL,Set<String>> findPackagesMap(String uri)
                                     throws IOException

Parameters:

uri - URL

Returns:

a map of subpackages from jars or dirs

Throws:

IOException - in case of IO errors