Binder is Android's inter-process communication mechanism. Each call to Binder.clearCallingIdentity() should be followed by Binder.restoreCallingIdentity() in a finally block. Otherwise the wrong Binder identity may be used by subsequent code.

For example: java long token = Binder.clearCallingIdentity(); // Issue a Binder call (may throw an Exception). someBinderInterface.makeCall(); Binder.restoreCallingIdentity(token);

The above code should be rewritten as: java long token = Binder.clearCallingIdentity(); try { // Issue a Binder call (may throw an Exception). someBinderInterface.makeCall(); } finally { Binder.restoreCallingIdentity(token); }