Package org.hibernate.search.util

Class ClassLoaderHelper

java.lang.Object

org.hibernate.search.util.ClassLoaderHelper

public class ClassLoaderHelper
extends Object

Utility class to load instances of other classes by using a fully qualified name, or from a class type. Uses reflection and throws SearchException(s) with proper descriptions of the error, like the target class is missing a proper constructor, is an interface, is not found...

Method Summary

Modifier and Type	Method	Description
static Analyzer	analyzerInstanceFromClass(Class<?> classToInstantiate, Version luceneMatchVersion)
static Enumeration<URL>	getResources(String resourceName, Class<?> caller)
static <T> T	instanceFromClass(Class<T> targetSuperType, Class<?> classToLoad, String componentDescription)	Creates an instance of target class
static <T> T	instanceFromName(Class<T> targetSuperType, String classNameToLoad, Class<?> caller, String componentDescription)	Creates an instance of a target class designed by fully qualified name

Methods inherited from class java.lang.Object

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

Method Details

getResources

public static Enumeration<URL> getResources(String resourceName,
 Class<?> caller)

instanceFromName

public static <T> T instanceFromName(Class<T> targetSuperType,
 String classNameToLoad,
 Class<?> caller,
 String componentDescription)

Creates an instance of a target class designed by fully qualified name

Type Parameters:

T - matches the type of targetSuperType: defines the return type

Parameters:

targetSuperType - the return type of the function, the classNameToLoad will be checked to be assignable to this type.

classNameToLoad - a fully qualified class name, whose type is assignable to targetSuperType

caller - the class of the caller, needed for classloading purposes

componentDescription - a meaningful description of the role the instance will have, used to enrich error messages to describe the context of the error

Returns:

a new instance of classNameToLoad

Throws:

SearchException - wrapping other error types with a proper error message for all kind of problems, like classNotFound, missing proper constructor, wrong type, security errors.

instanceFromClass

public static <T> T instanceFromClass(Class<T> targetSuperType,
 Class<?> classToLoad,
 String componentDescription)

Creates an instance of target class

Type Parameters:

T - the type of targetSuperType: defines the return type

Parameters:

targetSuperType - the created instance will be checked to be assignable to this type

classToLoad - the class to be instantiated

componentDescription - a role name/description to contextualize error messages

Returns:

a new instance of classToLoad

Throws:

SearchException - wrapping other error types with a proper error message for all kind of problems, like missing proper constructor, wrong type, security errors.

analyzerInstanceFromClass

public static Analyzer analyzerInstanceFromClass(Class<?> classToInstantiate,
 Version luceneMatchVersion)