android code obfuscation about gson

System.out.println (" before conversion str + + + + + + +>" + str);
lgrsp = gs.fromJson (str, LoginResponseInfo.class) ;/ / the JSON string into an object
System.out.println ("lgrsp + + + + + + +>" + lgrsp);

confused with other parts of the problem but did not find here , gs.fromJson () this method to print the parameter values ​​are correct, the result returned is null. NOTE : Do not confuse is not a problem .

confused script filled .
-keep class net.sf. ** {*;}
-keep class com.badlogic. ** {*;}
-keep class * implements com.badlogic.gdx.utils.Json *
-keep class com.google. ** {*;}

elsewhere in this package is also useful to a number of methods, such as the map, into json is correct. Tangle shi me ...

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this really do not know Oh
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wooden someone pointing forehead ? ? ? ?
------ reference --------------------------------------- < br> LZ not solve ? with demand ah