void deleteTable(String tablename) throws IOException {
HBaseAdmin admin = new HBaseAdmin(conf);
admin.getConnection().clearRegionCache();
byte[] tbytes = Bytes.toBytes(tablename);
if (admin.isTableEnabled(tbytes)) {
admin.disableTableAsync(tbytes);
}
while (!admin.isTableDisabled(tbytes)) {
try {
Thread.sleep(250);
} catch (InterruptedException e) {