J2ME is a micro Java runtime environment for resource-constrained devices.There are already many mobile devices that support MIDP 1.0 in J2ME.Many security threats exist in MIDP1.0 since the specification has only little security issues.It's supposed that the next version of MIDP will improve the security for the business information and personal privacy.The brief introductions of the J2ME and MIDP are given at first,the security threats and attacks in the J2ME environment are explained as following,then th...