Java读取类路径下的资源文件

一、工具类代码ResourceLoadUtil.java

import java.io.IOException;
import java.io.InputStream;
import java.net.URL;
import java.util.ArrayList;
import java.util.Enumeration;
import java.util.List;

public class ResourceLoadUtil {

    /**
     * @param args
     */
    public static void main(String[] args) {
        System.out.println("ByClazz...\n--------------------------");
        System.out.println(loadResourceByClazz(String.class, "/java/lang/String.class"));
        System.out.println(loadResourceByClazz(String.class, "/ResourceLoadUtil.class"));
        System.out.println();

        System.out.println("ByClasLoader...\n--------------------------");
        System.out.println(loadResourceByClassLoader("java/lang/String.class"));
        System.out.println(loadResourceByClassLoader("ResourceLoadUtil.class"));
        System.out.println();

        System.out.println("sByClasLoader...\n--------------------------");
        System.out.println(loadResourcesByClassLoader("java/lang/String.class"));
        System.out.println(loadResourcesByClassLoader("ResourceLoadUtil.class"));
        System.out.println(loadResourcesByClassLoader("struts-plugin.xml"));

    }

    /**
     * 根据Class加载资源文件
     * 
     * @param clazz
     * @param path
     *            以'/'开头的路径: 使用绝对路径寻找文件(以ClassPath为根路径开始)<br>
     *            否则: 使用相对路径寻找文件(相对于clazz位置路径开始)
     * @return
     */
    public static InputStream loadResourceByClazz(Class<?> clazz, String path) {
        return clazz.getResourceAsStream(path);
    }

    /**
     * 根据ClassLoader加载资源文件(单个), 使用默认的ClassLoader!
     * 
     * @param path
     *            不能以'/'开头的路径
     * @return
     */
    public static InputStream loadResourceByClassLoader(String path) {
        return loadResourceByClassLoader(null, path);
    }

    /**
     * 根据ClassLoader加载资源文件(单个), 使用默认的ClassLoader!
     * 
     * @param path
     *            不能以'/'开头的路径
     * @return
     */
    public static InputStream loadResourceByClassLoader(ClassLoader cl, String path) {
        if (cl == null) {
            cl = Thread.currentThread().getContextClassLoader();
        }
        return cl.getResourceAsStream(path);
    }

    /**
     * 根据ClassLoader加载资源文件(多个),使用默认的ClassLoader!
     * 
     * @param path
     *            不能以'/'开头的路径
     * @return
     */
    public static List<URL> loadResourcesByClassLoader(String path) {
        return loadResourcesByClassLoader(null, path);
    }

    /**
     * 根据ClassLoader加载资源文件(多个),使用指定的ClassLoader!
     * 
     * @param path
     *            不能以'/'开头的路径
     * @return
     */
    public static List<URL> loadResourcesByClassLoader(ClassLoader cl, String path) {
        if (cl == null) {
            cl = Thread.currentThread().getContextClassLoader();
        }
        List<URL> urlLst = new ArrayList<URL>();
        try {
            Enumeration<URL> urlsEnum = cl.getResources(path);
            while (urlsEnum.hasMoreElements()) {
                URL url = (URL) urlsEnum.nextElement();
                urlLst.add(url);
            }
        } catch (IOException e) {
            e.printStackTrace();
        }
        return urlLst;
    }
}

 

 

 

二、执行结果

ByClazz...
--------------------------
sun.net.www.protocol.jar.JarURLConnection$JarURLInputStream@11cfb549
java.io.BufferedInputStream@a422ede

ByClasLoader...
--------------------------
sun.net.www.protocol.jar.JarURLConnection$JarURLInputStream@7f12f614
java.io.BufferedInputStream@35d9dc39

sByClasLoader...
--------------------------
[jar:file:/D:/Java/jdk1.6.0_25/jre/lib/rt.jar!/java/lang/String.class]
[file:/E:/workspace/JBDS/Spring+Struts2-Integration/target/classes/ResourceLoadUtil.class]
[jar:file:/E:/360data/%e9%87%8d%e8%a6%81%e6%95%b0%e6%8d%ae/.m2/repository/org/apache/struts/struts2-spring-plugin/2.3.4.1/struts2-spring-plugin-2.3.4.1.jar!/struts-plugin.xml, jar:file:/E:/360data/%e9%87%8d%e8%a6%81%e6%95%b0%e6%8d%ae/.m2/repository/org/apache/struts/struts2-config-browser-plugin/2.3.4.1/struts2-config-browser-plugin-2.3.4.1.jar!/struts-plugin.xml]