这是错误信息：
java.lang.IllegalArgumentException: image == null!
at javax.imageio.ImageTypeSpecifier.createFromRenderedImage(ImageTypeSpecifier.java:925)
at javax.imageio.ImageIO.getWriter(ImageIO.java:1591)
at javax.imageio.ImageIO.write(ImageIO.java:1578)
at com.jit.ftp.FtpUtil.encodeImageToString(FtpUtil.java:212)
at com.jit.ftp.FtpUtil.imagesBookNow(FtpUtil.java:251)
at com.jit.jso.soil_manage.action.SoilAction.toViewSoil(SoilAction.java:292)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:606)
at org.springframework.web.bind.annotation.support.HandlerMethodInvoker.invokeHandlerMethod(HandlerMethodInvoker.java:176)
at org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter.invokeHandlerMethod(AnnotationMethodHandlerAdapter.java:440)
at org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter.handle(AnnotationMethodHandlerAdapter.java:428)
at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:925)
at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:856)
at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:936)
at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:827)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:621)
at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:812)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:722)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:304)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
at com.alibaba.druid.support.http.WebStatFilter.doFilter(WebStatFilter.java:124)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
at com.jit.filter.SessionFilter.doFilter(SessionFilter.java:53)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:88)
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:240)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:164)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:498)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:164)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:100)
at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:562)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118)
at org.apache.catalina.ha.session.JvmRouteBinderValve.invoke(JvmRouteBinderValve.java:218)
at org.apache.catalina.ha.tcp.ReplicationValve.invoke(ReplicationValve.java:333)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:394)
at org.apache.coyote.ajp.AjpAprProcessor.process(AjpAprProcessor.java:283)
at org.apache.coyote.ajp.AjpAprProtocol$AjpConnectionHandler.process(AjpAprProtocol.java:189)
at org.apache.tomcat.util.net.AprEndpoint$SocketProcessor.run(AprEndpoint.java:1714)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
at java.lang.Thread.run(Thread.java:745)
这是部分代码：
FTPClient ftp = new FTPClient();
int reply;
ftp.connect(url, port);// 连接FTP服务器
// 如果采用默认端口，可以使用ftp.connect(url)的方式直接连接FTP服务器
ftp.login(userName, passWord);// 登录
reply = ftp.getReplyCode();
ftp.enterLocalPassiveMode();
//将路径转成输入流后再转成64位base编码
FTPClient ftpc = new FTPClient();
boolean t=ftp.changeWorkingDirectory("/"+strList.get(1).toString().substring(1, strList.get(1).length()));
System.out.println("11"+t);
InputStream ips = ftp.retrieveFileStream(strList.get(0));
ftp.logout();
// closeConnections(ftpc);
String field = FtpUtil.encodeImageToString(strList.get(1)+"/"+strList.get(0),ips);//第一个参数路径是文件夹和图片的路径
pathList.add(field);
return "";
}
System.out.println(ips);
System.out.println(imagePath);
System.out.println(type);
BufferedImage image = ImageIO.read(ips);
System.out.println(image);
String imageString = null;
ByteArrayOutputStream bos = new ByteArrayOutputStream();
ImageIO.write(image, type, bos);
byte[] imageBytes = bos.toByteArray();
BASE64Encoder encoder = new BASE64Encoder();
imageString = encoder.encode(imageBytes);
bos.close();
return "data:image/jpeg;base64,"+imageString;
} catch (IOException e) {
e.printStackTrace();
}
return "";
只有png格式的图片无法读出，BufferedImage image = ImageIO.read(ips);
image 返回的是null ,求大神解答
