如何在android中区分android主联系人？

<uses-permission android:name="android.permission.READ_CONTACTS" />

String[] projection = new String[]{ContactsContract.Contacts._ID, ContactsContract.Contacts.DISPLAY_NAME, ContactsContract.Contacts.STARRED};
String selection = ContactsContract.Contacts.STARRED + "=?";
String[] selectionArgs = new String[]{"1"};
Cursor cursor = getContentResolver().query(ContactsContract.Contacts.CONTENT_URI, projection, selection, selectionArgs, null);

while (cursor.moveToNext()) {
    String contactId = cursor.getString(cursor.getColumnIndex(ContactsContract.Contacts._ID));
    String displayName = cursor.getString(cursor.getColumnIndex(ContactsContract.Contacts.DISPLAY_NAME));
    // 处理联系人信息
}

cursor.close();