class getResourceAsStream 和 classloader getResourceAsStream获取资源的不同

/**
 *
 */
package cn.json.classloader;

import java.io.InputStream;

/**
 * @author json
 * 
 * @date 2014-5-7
 * 
 * @version 1.0
 */
public class GetResourceByClassAndClassLoader {

    /**
     * class 获取资源是相对于当前class所在路径去获取
     * 
     * classloader 是相对于classpath去获取相应的资源，采用绝对路径
     * 
     * @param args
     */
    public static void main(String[] args) {
        GetResourceByClassAndClassLoader bean = new GetResourceByClassAndClassLoader();
        InputStream is = bean.getClass().getResourceAsStream("../../../beans.xml");
        if (is == null) {
            System.out.println("resources not found!");
        }
        is = null;
        is = bean.getClass().getResourceAsStream("/beans.xml");
        if (is == null) {
            System.out.println("resources not found!");
        }
        is = null;
        is = bean.getClass().getClassLoader().getResourceAsStream("beans.xml");
        if (is == null) {
            System.out.println("resources not found!");
        }
    }
}