加载器

public static void main(String[] args) {
//        System.out.println(System.getProperty("sun.boot.class.path"));
//        System.out.println(System.getProperty("java.ext.dirs"));
//        System.out.println(System.getProperty("java.class.path"));
        System.out.println("BootstrapClassLoader 的加载路径: ");  
        URL[] urls = sun.misc.Launcher.getBootstrapClassPath().getURLs();  
        for(URL url : urls)  
            System.out.println(url);  
        System.out.println("----------------------------");  
        //取得扩展类加载器  
        URLClassLoader extClassLoader = (URLClassLoader)ClassLoader.getSystemClassLoader().getParent();  
        System.out.println(extClassLoader);  
        System.out.println("扩展类加载器 的加载路径: ");  
        urls = extClassLoader.getURLs();  
        for(URL url : urls)  
            System.out.println(url);  
        System.out.println("----------------------------");  
        //取得应用(系统)类加载器  
        URLClassLoader appClassLoader = (URLClassLoader)ClassLoader.getSystemClassLoader();  
        System.out.println(appClassLoader);  
        System.out.println("应用(系统)类加载器 的加载路径: ");  
        urls = appClassLoader.getURLs();  
        for(URL url : urls)  
            System.out.println(url);  
        System.out.println("----------------------------");   
    }

BootstrapClassLoader 的加载路径: 
file:/C:/Program%20Files/Java/jdk1.8.0_91/jre/lib/resources.jar
file:/C:/Program%20Files/Java/jdk1.8.0_91/jre/lib/rt.jar
file:/C:/Program%20Files/Java/jdk1.8.0_91/jre/lib/sunrsasign.jar
file:/C:/Program%20Files/Java/jdk1.8.0_91/jre/lib/jsse.jar
file:/C:/Program%20Files/Java/jdk1.8.0_91/jre/lib/jce.jar
file:/C:/Program%20Files/Java/jdk1.8.0_91/jre/lib/charsets.jar
file:/C:/Program%20Files/Java/jdk1.8.0_91/jre/lib/jfr.jar
file:/C:/Program%20Files/Java/jdk1.8.0_91/jre/classes
----------------------------
sun.misc.Launcher$ExtClassLoader@5e481248
扩展类加载器 的加载路径: 
file:/C:/Program%20Files/Java/jdk1.8.0_91/jre/lib/ext/access-bridge-64.jar
file:/C:/Program%20Files/Java/jdk1.8.0_91/jre/lib/ext/cldrdata.jar
file:/C:/Program%20Files/Java/jdk1.8.0_91/jre/lib/ext/dnsns.jar
file:/C:/Program%20Files/Java/jdk1.8.0_91/jre/lib/ext/jaccess.jar
file:/C:/Program%20Files/Java/jdk1.8.0_91/jre/lib/ext/jfxrt.jar
file:/C:/Program%20Files/Java/jdk1.8.0_91/jre/lib/ext/localedata.jar
file:/C:/Program%20Files/Java/jdk1.8.0_91/jre/lib/ext/nashorn.jar
file:/C:/Program%20Files/Java/jdk1.8.0_91/jre/lib/ext/sunec.jar
file:/C:/Program%20Files/Java/jdk1.8.0_91/jre/lib/ext/sunjce_provider.jar
file:/C:/Program%20Files/Java/jdk1.8.0_91/jre/lib/ext/sunmscapi.jar
file:/C:/Program%20Files/Java/jdk1.8.0_91/jre/lib/ext/sunpkcs11.jar
file:/C:/Program%20Files/Java/jdk1.8.0_91/jre/lib/ext/zipfs.jar
----------------------------
sun.misc.Launcher$AppClassLoader@1d44bcfa

应用(系统)类加载器 的加载路径: 

这里就打印的jar是系统的classpath路径：System.getProperty("java.class.path");
即WEB-INF/classes/里面的class文件 和 项目引用的jar