org.springframework.util
Class ClassLoaderUtils

public abstract class ClassLoaderUtils

Utility class for diagnostic purposes, to analyze the ClassLoader hierarchy for any object.

Author:

Rod Johnson

Since: 02 April 2001

See Also: ClassLoader

public static String addResourcePathToPackagePath(Class clazz, String resourceName)

Return a path suitable for use with ClassLoader.getResource (also suitable for use with Class.getResource by prepending a slash ('/') to the return value. Built by taking the package of the specified class file, converting all dots ('.') to slashes ('/'), adding a trailing slash if necesssary, and concatenating the specified resource name to this. As such, this function may be used to build a path suitable for loading a resource file that is in the same package as a class file.

Parameters:

clazz the Class - whose package will be used as the base.

resourceName - the resource name to append. A leading slash is optional.

Returns: the built-up resource path

See Also:

java.lang.ClassLoader.getResource(java.lang.String), java.lang.Class.getResource(java.lang.String)

public static String classNameWithoutPackagePrefix(Class clazz)

Given a fully qualified name, return a class name: e.g. com.foo.Bar returns Bar, com.foo.Bar$Inner returns Bar$Inner.

Parameters:

clazz - class to find name for

Returns: the class name without the package prefix. Will include any enclosing class name, which is also after the dot.

public static String classPackageAsResourcePath(Class clazz)

Given an input class object, returns a string which consists of the class's package name as a pathname, i.e., all dots ('.') are replaced by slashes ('/'). Neither a leading nor trailing slash is added. The result could be concatenated with a slash and the name of a resource, and fed directly to ClassLoader.getResource(). For it to be fed to Class.getResource, a leading slash would also have to be prepended to the return value.

Parameters:

clazz the input - class. A null value or the default (empty) package will result in an empty string ("") being returned.

Returns: a path which represents the package name

See Also:

java.lang.ClassLoader.getResource(java.lang.String), java.lang.Class.getResource(java.lang.String)

public static String showClassLoaderHierarchy(Object obj, String role, String delim, String tabText)

Show the class loader hierarchy for this class.

Parameters:

obj - object to analyze loader hierarchy for

role - a description of the role of this class in the application (e.g., "servlet" or "EJB reference")

delim - line break

tabText - text to use to set tabs

Returns: a String showing the class loader hierarchy for this class

public static String showClassLoaderHierarchy(ClassLoader cl, String delim, String tabText, int indent)

Show the class loader hierarchy for this class.

Parameters:

cl - class loader to analyze hierarchy for

delim - line break

tabText - text to use to set tabs

indent - nesting level (from 0) of this loader; used in pretty printing

Returns: a String showing the class loader hierarchy for this class