public class JarUtil
{
    private String jarName;
    private String jarPath;
        
    public JarUtil(Class clazz)
    {
        String path = clazz.getProtectionDomain().getCodeSource().getLocation()
                .getFile();
        try
        {
            path = java.net.URLDecoder.decode(path, "UTF-8");
        }
        catch (java.io.UnsupportedEncodingException e)
        {
            e.printStackTrace();
        }

        java.io.File jarFile = new java.io.File(path);
        this.jarName = jarFile.getName();

        java.io.File parent = jarFile.getParentFile();
        if (parent != null)
        {
            this.jarPath = parent.getAbsolutePath();
        }
    }

    /**
     * 獲取Class類所在Jar包的名稱
     *
     * @return Jar包名 (例如：C:\temp\demo.jar 則返回 demo.jar )
     */
    public String getJarName()
    {
        try
        {
            return java.net.URLDecoder.decode(this.jarName, "UTF-8");
        }
        catch (java.io.UnsupportedEncodingException e)
        {
            e.printStackTrace();
        }
        return null;
    }

    /**
     * 取得Class類所在的Jar包路徑
     *
     * @return 返回一個路徑 (例如：C:\temp\demo.jar 則返回 C:\temp )
     */
    public String getJarPath()
    {
        try
        {
            return java.net.URLDecoder.decode(this.jarPath, "UTF-8");
        }
        catch (java.io.UnsupportedEncodingException e)
        {
            e.printStackTrace();
        }
        return null;
    }

    public static void main(String[] args) throws Exception
    {
        JarUtil ju = new JarUtil(JarUtil.class);
        System.out.println("Jar name: " + ju.getJarName());
        System.out.println("Jar path: " + ju.getJarPath());
    }
}