Spring Framework example source code file (ClassLoaderUtils.java)

This example Spring Framework source code file (ClassLoaderUtils.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - Spring Framework tags/keywords

classloader, classloader, classloaderutils, classloaderutils, string, string, stringbuffer, stringbuffer

The Spring Framework ClassLoaderUtils.java source code

/*
 * Copyright 2002-2008 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.springframework.util;

/**
 * Utility class for diagnostic purposes, to analyze the
 * ClassLoader hierarchy for any given object or class loader.
 *
 * @author Rod Johnson
 * @author Juergen Hoeller
 * @since 02 April 2001
 * @deprecated as of Spring 2.5, to be removed in Spring 3.0
 * @see java.lang.ClassLoader
 */
public abstract class ClassLoaderUtils {

	/**
	 * Show the class loader hierarchy for this class.
	 * Uses default line break and tab text characters.
	 * @param obj object to analyze loader hierarchy for
	 * @param role a description of the role of this class in the application
	 * (e.g., "servlet" or "EJB reference")
	 * @return a String showing the class loader hierarchy for this class
	 */
	public static String showClassLoaderHierarchy(Object obj, String role) {
		return showClassLoaderHierarchy(obj, role, "\n", "\t");
	}

	/**
	 * Show the class loader hierarchy for this class.
	 * @param obj object to analyze loader hierarchy for
	 * @param role a description of the role of this class in the application
	 * (e.g., "servlet" or "EJB reference")
	 * @param lineBreak line break
	 * @param tabText text to use to set tabs
	 * @return a String showing the class loader hierarchy for this class
	 */
	public static String showClassLoaderHierarchy(Object obj, String role, String lineBreak, String tabText) {
		String s = "object of " + obj.getClass() + ": role is " + role + lineBreak;
		return s + showClassLoaderHierarchy(obj.getClass().getClassLoader(), lineBreak, tabText, 0);
	}

	/**
	 * Show the class loader hierarchy for the given class loader.
	 * Uses default line break and tab text characters.
	 * @param cl class loader to analyze hierarchy for
	 * @return a String showing the class loader hierarchy for this class
	 */
	public static String showClassLoaderHierarchy(ClassLoader cl) {
		return showClassLoaderHierarchy(cl, "\n", "\t");
	}

	/**
	 * Show the class loader hierarchy for the given class loader.
	 * @param cl class loader to analyze hierarchy for
	 * @param lineBreak line break
	 * @param tabText text to use to set tabs
	 * @return a String showing the class loader hierarchy for this class
	 */
	public static String showClassLoaderHierarchy(ClassLoader cl, String lineBreak, String tabText) {
		return showClassLoaderHierarchy(cl, lineBreak, tabText, 0);
	}

	/**
	 * Show the class loader hierarchy for the given class loader.
	 * @param cl class loader to analyze hierarchy for
	 * @param lineBreak line break
	 * @param tabText text to use to set tabs
	 * @param indent nesting level (from 0) of this loader; used in pretty printing
	 * @return a String showing the class loader hierarchy for this class
	 */
	private static String showClassLoaderHierarchy(ClassLoader cl, String lineBreak, String tabText, int indent) {
		if (cl == null) {
			ClassLoader ccl = Thread.currentThread().getContextClassLoader();
			return "context class loader=[" + ccl + "] hashCode=" + ccl.hashCode();
		}
		StringBuffer buf = new StringBuffer();
		for (int i = 0; i < indent; i++) {
			buf.append(tabText);
		}
		buf.append("[").append(cl).append("] hashCode=").append(cl.hashCode()).append(lineBreak);
		ClassLoader parent = cl.getParent();
		return buf.toString() + showClassLoaderHierarchy(parent, lineBreak, tabText, indent + 1);
	}

}