转自 http://www.cnblogs.com/wanqieddy/archive/2012/09/24/2700064.html
D:\android_code\0708\tools>adb devices
List of devices attached
015d2109f414120e offline
015d2109f414120e device
D:\android_code\0708\tools>adb push Y:\out\target\product\kai\system\framework\framework.jar system/framework
error: device offline
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解决
adb kill-server
adb start-server