将动态库打包在Jar包并调用的方法

       首先应该知道，无法直接加载Jar包中的动态库（dll、so）

       实现方法：使用输入输出流将动态库写在别的目录进行调用

     //getResourceAsStream以JAR中根路径为开始点
    private synchronized static void loadLib(String libName) throws IOException {
        String systemType = System.getProperty("os.name");
        String libExtension = (systemType.toLowerCase().indexOf("win")!=-1) ? ".dll" : ".so";

        String libFullName = libName + libExtension;
        //动态库的输出目录 可自行设置
        String nativeTempDir = System.getProperty("java.io.tmpdir");

        InputStream in = null;
        BufferedInputStream reader = null;
        FileOutputStream writer = null;

        File extractedLibFile = new File(nativeTempDir+File.separator+libFullName);
        if(!extractedLibFile.exists()){
            try {
                // “/”代表Jar包的根目录
                in = SecretKeyKeeper.class.getResourceAsStream("/" + libFullName);
                if(in==null)
                    in =  SecretKeyKeeper.class.getResourceAsStream(libFullName);
                SecretKeyKeeper.class.getResource(libFullName);
                reader = new BufferedInputStream(in);
                writer = new FileOutputStream(extractedLibFile);

                byte[] buffer = new byte[1024];

                while (reader.read(buffer) > 0){
                    writer.write(buffer);
                    buffer = new byte[1024];
                }
            } catch (IOException e){
                e.printStackTrace();
            } finally {
                if(in!=null)
                    in.close();
                if(writer!=null)
                    writer.close();
            }
        }
        System.load(extractedLibFile.toString());
    }