build.gradle - Android Studio - Cannot find symbol class -

when run app, android studio notifies me error in gradle build.

could me understand how fix problem?

mapsactivity

public class mapsactivity extends fragmentactivity implements onmapreadycallback {  private googlemap mmap; databasehelper mydb;   @override protected void oncreate(bundle savedinstancestate) {     super.oncreate(savedinstancestate);     setcontentview(r.layout.activity_maps);     // obtain supportmapfragment , notified when map ready used.     supportmapfragment mapfragment = (supportmapfragment) getsupportfragmentmanager()             .findfragmentbyid(r.id.map);     mapfragment.getmapasync(this);     addmarkers(); }  @override public void onmapready(googlemap googlemap) {     mmap = googlemap;      // add marker in sydney , move camera     latlng sydney = new latlng(-34, 151);     latlng ruvo = new latlng(-45, 123);     mmap.addmarker(new markeroptions().position(sydney).title("marker in sydney"));     mmap.addmarker(new markeroptions().position(ruvo).title("marker in sydney"));     mmap.movecamera(cameraupdatefactory.newlatlng(ruvo)); }  public void onsearch(view view) {     edittext textcity = (edittext) findviewbyid(r.id.textcity);     string location = textcity.gettext().tostring();     list<android.location.address> addresslist = null;      if (location != null) {         geocoder geocoder = new geocoder(this);         try {             addresslist = geocoder.getfromlocationname(location, 1);         } catch (ioexception e) {             e.printstacktrace();         }         android.location.address address = addresslist.get(0);         latlng latlng = new latlng(address.getlatitude(), address.getlongitude());         mmap.addmarker(new markeroptions().position(latlng).title("marker pointed"));         mmap.animatecamera(cameraupdatefactory.newlatlng(latlng));     } else {         textcity.sethint("enter valid city");         //textcity.settextcolor();     }  }  public void addmarkers() {     arraylist<overlayitem> items = new arraylist<overlayitem>();     cursor database = mydb.display();         if (database.getcount()== 0) {             toast.maketext(this, "nothing found", toast.length_long).show();             return;         }         database.movetofirst();         {             int latitude = (int) (database.getdouble(database.getcolumnindex("lat")) * 1e6);             int longitude = (int) (database.getdouble(database.getcolumnindex("long")) * 1e6);             items.add(new overlayitem(new geopoint(latitude, longitude)));         } while (database.movetonext());  }  } 

build.gradle

apply plugin: 'com.android.application'  android {   compilesdkversion 23   buildtoolsversion "23.0.3"      defaultconfig {       applicationid "com.example.android.sqlite"       minsdkversion 16       targetsdkversion 23       versioncode 1       versionname "1.0"     }   buildtypes {       release {           minifyenabled false           proguardfiles getdefaultproguardfile('proguard-android.txt'), 'proguard-rules.pro'       }   } }  dependencies {   compile filetree(dir: 'libs', include: ['*.jar'])   testcompile 'junit:junit:4.12'   compile 'com.android.support:appcompat-v7:23.3.0'   compile 'com.google.android.gms:play-services:9.2.0' } 

error messages:

error:(82, 19) error: cannot find symbol class overlayitem error:(82, 54) error: cannot find symbol class overlayitem error:(92, 31) error: cannot find symbol class overlayitem error:(92, 47) error: cannot find symbol class geopoint error:execution failed task ':app:compiledebugjavawithjavac'. 

compilation failed; see compiler error output details.`