Program: 36341
Project: 36341
Buggy source:
public void initialize(){
  courses=((MainApplication)getApplication()).getDataHolderInstance().getCourses();
  campus=((MainApplication)getApplication()).getDataHolderInstance().getCampus();
  registerNumber=((MainApplication)getApplication()).getDataHolderInstance().getRegisterNumber();
  navigationTabs=Arrays.asList(getResources().getStringArray(R.array.navigation_tab));
  headerCampus=(TextView)drawerLayout.findViewById(R.id.header_campus);
  headerUsername=(TextView)drawerLayout.findViewById(R.id.header_username);
  drawerLayout=(DrawerLayout)findViewById(R.id.drawer_layout);
  mainContent=(LinearLayout)findViewById(R.id.llMainContent);
  final Toolbar toolbar=(Toolbar)findViewById(R.id.toolbar);
  setSupportActionBar(toolbar);
  final ActionBar actionBar=getSupportActionBar();
  if (actionBar != null) {
    ActionBarDrawerToggle mDrawerToggle=new ActionBarDrawerToggle(this,drawerLayout,toolbar,R.string.navigation_drawer_open,R.string.navigation_drawer_close);
    drawerLayout.setDrawerListener(mDrawerToggle);
    actionBar.setDisplayHomeAsUpEnabled(true);
    actionBar.setHomeButtonEnabled(true);
    mDrawerToggle.syncState();
  }
  headerUsername.setText(registerNumber);
  headerCampus.setText(toTitleCase(campus));
  NavigationView view=(NavigationView)findViewById(R.id.navigation_view);
  view.setNavigationItemSelectedListener(new NavigationView.OnNavigationItemSelectedListener(){
    @Override public boolean onNavigationItemSelected(    MenuItem menuItem){
      Fragment fragment=null;
      int position=0;
      String navString=(String)menuItem.getTitle();
      menuItem.setChecked(true);
      FragmentTransaction fragmentTransaction=getSupportFragmentManager().beginTransaction();
switch (navString) {
case "String_Node_Str":
        fragment=TodayFragment.newInstance();
      position=0;
    break;
case "String_Node_Str":
  fragment=CoursesFragment.newInstance();
position=1;
break;
case "String_Node_Str":
fragment=TimetableFragment.newInstance();
position=2;
break;
case "String_Node_Str":
fragment=GradesFragment.newInstance();
position=3;
break;
case "String_Node_Str":
fragment=SettingsFragment.newInstance();
position=4;
break;
case "String_Node_Str":
fragment=MessagesFragment.newInstance();
position=5;
break;
case "String_Node_Str":
fragment=AboutFragment.newInstance();
position=6;
break;
}
fragmentTransaction.replace(R.id.flContent,fragment,navigationTabs.get(position)).addToBackStack(null).commit();
drawerLayout.closeDrawers();
return true;
}
}
);
getSupportFragmentManager().beginTransaction().add(R.id.flContent,new TodayFragment(),TodayFragment.class.getSimpleName()).commit();
}

Fixed version (ground truth):
public void initialize(){
  courses=((MainApplication)getApplication()).getDataHolderInstance().getCourses();
  campus=((MainApplication)getApplication()).getDataHolderInstance().getCampus();
  registerNumber=((MainApplication)getApplication()).getDataHolderInstance().getRegisterNumber();
  navigationTabs=Arrays.asList(getResources().getStringArray(R.array.navigation_tab));
  drawerLayout=(DrawerLayout)findViewById(R.id.drawer_layout);
  mainContent=(LinearLayout)findViewById(R.id.llMainContent);
  headerCampus=(TextView)drawerLayout.findViewById(R.id.header_campus);
  headerUsername=(TextView)drawerLayout.findViewById(R.id.header_username);
  final Toolbar toolbar=(Toolbar)findViewById(R.id.toolbar);
  setSupportActionBar(toolbar);
  final ActionBar actionBar=getSupportActionBar();
  if (actionBar != null) {
    ActionBarDrawerToggle mDrawerToggle=new ActionBarDrawerToggle(this,drawerLayout,toolbar,R.string.navigation_drawer_open,R.string.navigation_drawer_close);
    drawerLayout.setDrawerListener(mDrawerToggle);
    actionBar.setDisplayHomeAsUpEnabled(true);
    actionBar.setHomeButtonEnabled(true);
    mDrawerToggle.syncState();
  }
  headerUsername.setText(registerNumber);
  headerCampus.setText(toTitleCase(campus));
  NavigationView view=(NavigationView)findViewById(R.id.navigation_view);
  view.setNavigationItemSelectedListener(new NavigationView.OnNavigationItemSelectedListener(){
    @Override public boolean onNavigationItemSelected(    MenuItem menuItem){
      Fragment fragment=null;
      int position=0;
      String navString=(String)menuItem.getTitle();
      menuItem.setChecked(true);
      FragmentTransaction fragmentTransaction=getSupportFragmentManager().beginTransaction();
switch (navString) {
case "String_Node_Str":
        fragment=TodayFragment.newInstance();
      position=0;
    break;
case "String_Node_Str":
  fragment=CoursesFragment.newInstance();
position=1;
break;
case "String_Node_Str":
fragment=TimetableFragment.newInstance();
position=2;
break;
case "String_Node_Str":
fragment=GradesFragment.newInstance();
position=3;
break;
case "String_Node_Str":
fragment=SettingsFragment.newInstance();
position=4;
break;
case "String_Node_Str":
fragment=MessagesFragment.newInstance();
position=5;
break;
case "String_Node_Str":
fragment=AboutFragment.newInstance();
position=6;
break;
}
fragmentTransaction.replace(R.id.flContent,fragment,navigationTabs.get(position)).addToBackStack(null).commit();
drawerLayout.closeDrawers();
return true;
}
}
);
getSupportFragmentManager().beginTransaction().add(R.id.flContent,new TodayFragment(),TodayFragment.class.getSimpleName()).commit();
}