Resuelva el problema de la solicitud entre dominios, regístrelo

浏览器出于安全的考虑，不允许跨域请求，试了网上很多种方法，还是觉得最直接的方法好，给响应头添加以下字段即可，浏览器端ajax发起请求无需添加额外的header。
							 // 响应
							StringBuilder responseContext = new StringBuilder();
							responseContext.append(base64Img);
							StringBuilder response = new StringBuilder();
							// 1)  HTTP协议版本、状态代码、描述
							response.append("HTTP/1.1").append(BLANK).append("200").append(BLANK).append("OK")
									.append(CRLF);
							// 2)  响应头(Response Head)
							response.append("Server:km Server/0.0.1").append(CRLF);
							response.append("Date:").append(new Date()).append(CRLF);
							response.append("Content-type:text/html;charset=utf-8").append(CRLF);
							// 正文长度：字节长度
							response.append("Content-Length:").append(responseContext.toString().getBytes().length)
									.append(CRLF);
							// 这是允许跨域访问的响应头处理
							response.append("Access-Control-Allow-Origin: *").append(CRLF);
							response.append("Access-Control-Allow-Methods: POST,GET,OPTIONS,DELETE").append(CRLF);
							response.append("Access-Control-Allow-Headers: X-Requested-With, Content-Type")
									.append(CRLF);
							// 3)正文之前
							response.append(CRLF);
							// 4)正文
							response.append(responseContext);
							System.out.println(responseContext);
							// 输出流
							BufferedWriter bw = new BufferedWriter(new OutputStreamWriter(socket.getOutputStream()));
							bw.write(response.toString());
							bw.flush();
							bw.close();
							socket.close();