Project获取资源需要一个启点，加载资源的动作是由ClassLoader来完成的。 Class对象和当前线程对象可以找到当前加载资源的ClassLoader， 通过ClassLoader的getResource(String name)方法及其它衍生出来的方法可以找到Application的启点及获取相关资源

private void display() {
            path=this.getClass().getResource("/loadresource").getPath();        System.out.println(path);        path=this.getClass().getResource("/loadresource/bp.txt").getPath();        System.out.println(path);        path=this.getClass().getResource("/").getPath();        System.out.println(path);        URL url=this.getClass().getResource("loadresource/bp.txt");        System.out.println("Is Null:"+(url==null));                path=GetResouceTest.class.getClassLoader().getResource("").getPath();        System.out.println(path);        path=GetResouceTest.class.getClassLoader().getResource("loadresource/bp.txt").getPath();        System.out.println(path);        url=GetResouceTest.class.getClassLoader().getResource("/loadresource/bp.txt");        System.out.println("Is Null:"+(url==null));                        path=Thread.currentThread().getContextClassLoader().getResource("").getPath();        System.out.println(path);        path=Thread.currentThread().getContextClassLoader().getResource("loadresource/bp.txt").getPath();        System.out.println(path);        url=Thread.currentThread().getContextClassLoader().getResource("loadresource/bp.txt");        System.out.println("Is Null:"+(url==null));        url=Thread.currentThread().getContextClassLoader().getResource("/loadresource/bp.txt");        System.out.println("Is Null:"+(url==null));            }

/E:/java/workspace/test/bin/loadresource/E:/java/workspace/test/bin/loadresource/bp.txt/E:/java/workspace/test/bin/Is Null:true/E:/java/workspace/test/bin//E:/java/workspace/test/bin/loadresource/bp.txtIs Null:true/E:/java/workspace/test/bin//E:/java/workspace/test/bin/loadresource/bp.txtIs Null:falseIs Null:true

/**     * Finds a resource with a given name.  The rules for searching resources     * associated with a given class are implemented by the defining     * {
    @linkplain ClassLoader class loader} of the class.  This method     * delegates to this object's class loader.  If this object was loaded by     * the bootstrap class loader, the method delegates to {
    @link     * ClassLoader#getSystemResource}.     *     * 
 Before delegation, an absolute resource name is constructed from the     * given resource name using this algorithm:     *     * 
     
           *     * 
      
 If the {
    @code name} begins with a {
    @code '/'}     * ('\u002f'), then the absolute name of the resource is the     * portion of the {
    @code name} following the {
    @code '/'}.     *     * 
      
 Otherwise, the absolute name is of the following form:     *     * 
       
             *   {
    @code modified_package_name/name}     * 
       
     *     * 
 Where the {
    @code modified_package_name} is the package name of this     * object with {
    @code '/'} substituted for {
    @code '.'}     * ('\u002e').     *     * 
     
     *     * @param  name name of the desired resource     * @return      A  {
    @link java.net.URL} object or {
    @code null} if no     *              resource with this name is found     * @since  JDK1.1     */    public java.net.URL getResource(String name) {        name = resolveName(name);        ClassLoader cl = getClassLoader0();        if (cl==null) {            // A system class.            return ClassLoader.getSystemResource(name);        }        return cl.getResource(name);    }

/**     * Add a package name prefix if the name is not absolute Remove leading "/"     * if name is absolute     */    private String resolveName(String name) {        if (name == null) {            return name;        }        if (!name.startsWith("/")) {            Class
      c = this;            while (c.isArray()) {                c = c.getComponentType();            }            String baseName = c.getName();            int index = baseName.lastIndexOf('.');            if (index != -1) {                name = baseName.substring(0, index).replace('.', '/')                    +"/"+name;            }        } else {            name = name.substring(1);        }        return name;    }