Applet upload IOException无效的Http响应

Question

I use applet for scanning and uploading images by POST to PHP address, when I test on localhost it works but when i upload remotely i get an error not every time, and in xampp log i get 302 status error.

GRAVE: null
java.io.IOException: Invalid Http response
    at sun.net.www.protocol.http.HttpURLConnection.getInputStream0(Unknown Source)
    at sun.net.www.protocol.http.HttpURLConnection.access$200(Unknown Source)
    at sun.net.www.protocol.http.HttpURLConnection$9.run(Unknown Source)
    at sun.net.www.protocol.http.HttpURLConnection$9.run(Unknown Source)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.security.AccessController.doPrivilegedWithCombiner(Unknown Source)
    at sun.net.www.protocol.http.HttpURLConnection.getInputStream(Unknown Source)
    at UploaderExample.upload(UploaderExample.java:65)
    at ScannerApplet.uploadImages(ScannerApplet.java:313)
    at ScannerApplet.actionPerformed(ScannerApplet.java:157)
    at java.awt.Button.processActionEvent(Unknown Source)
    at java.awt.Button.processEvent(Unknown Source)
    at java.awt.Component.dispatchEventImpl(Unknown Source)
    at java.awt.Component.dispatchEvent(Unknown Source)
    at java.awt.EventQueue.dispatchEventImpl(Unknown Source)
    at java.awt.EventQueue.access$500(Unknown Source)
    at java.awt.EventQueue$3.run(Unknown Source)
    at java.awt.EventQueue$3.run(Unknown Source)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(Unknown Source)
    at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(Unknown Source)
    at java.awt.EventQueue$4.run(Unknown Source)
    at java.awt.EventQueue$4.run(Unknown Source)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(Unknown Source)
    at java.awt.EventQueue.dispatchEvent(Unknown Source)
    at java.awt.EventDispatchThread.pumpOneEventForFilters(Unknown Source)
    at java.awt.EventDispatchThread.pumpEventsForFilter(Unknown Source)
    at java.awt.EventDispatchThread.pumpEventsForHierarchy(Unknown Source)
    at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
    at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
    at java.awt.EventDispatchThread.run(Unknown Source)