SpringBoot 项目 读取本地图片显示页面的方法

前台：

//picPath 位图片在服务器上存的位置，如“D:/gsPic/20220105/20220105192943227.jpg”
//name为项目访问名称，没有可不写
<img src="/name/getPic?picName=+ picPath">

后台：

1.在SpringBootApplication启动类中添加如下方法,配饰访问路径

/**
     * 在SpringBootApplication启动类中添加如下方法
     * @return
     */
    @Bean
    public ServletRegistrationBean getServletRegistrationBean() {
          
    
        //放入自己的Servlet对象实例
        ServletRegistrationBean bean = new ServletRegistrationBean(new GetPic());     
        //访问路径值
        bean.addUrlMappings("/getPic");  
         //一定要返回ServletRegistrationBean
        return bean;
    }

2.新建类，去把图片以流的形式写回页面

public class GetPic extends javax.servlet.http.HttpServlet implements javax.servlet.Servlet {
          
   

	/**
	 * 
	 */
	private static final long serialVersionUID = 1L;


	/*
	 * (non-Java-doc)
	 * 
	 * @see javax.servlet.http.HttpServlet#doGet(HttpServletRequest request,
	 *      HttpServletResponse response)
	 */
	protected void doGet(HttpServletRequest request,
                         HttpServletResponse response) throws ServletException, IOException {
          
   
		doPost(request, response);
	}

	/*
	 * (non-Java-doc)
	 * 
	 * @see javax.servlet.http.HttpServlet#doPost(HttpServletRequest request,
	 *      HttpServletResponse response)
	 */
	protected void doPost(HttpServletRequest request,
                          HttpServletResponse response) throws ServletException, IOException {
          
   
		String picName=request.getParameter("picName").toString();
		File f = null;
		f = new File(picName);
		if (f.exists()) {
          
   
			tofile(f, response, "image/jpg");
		}
	}
	
	public void tofile(File file, HttpServletResponse response, String contentType){
          
   
		try {
          
   
			FileInputStream in = new FileInputStream(file);
			byte[] buf = new byte[(int) in.available()];
			in.read(buf);
			response.setContentType(contentType);
			OutputStream toClient = response.getOutputStream();
			toClient.write(buf);
			toClient.flush();
			toClient.close();
			in.close();
		} catch (Exception e) {
          
   
			//e.printStackTrace();
		}
	}
}